Merge branch 'linux-linaro-lsk-v4.4' of http://git.linaro.org/kernel/linux-linaro-stable into ti-lsk-linux-4.4.y

TI-Feature: linaro-stable-4-4
TI-Tree: http://git.linaro.org/kernel/linux-linaro-stable.git
TI-Branch: linux-linaro-lsk-v4.4

* 'linux-linaro-lsk-v4.4' of http://git.linaro.org/kernel/linux-linaro-stable: (366 commits)
  Linux 4.4.150
  x86/speculation/l1tf: Exempt zeroed PTEs from inversion
  Linux 4.4.149
  x86/mm: Add TLB purge to free pmd/pte page interfaces
  ioremap: Update pgtable free interfaces with addr
  Bluetooth: hidp: buffer overflow in hidp_process_report
  ASoC: Intel: cht_bsw_max98090_ti: Fix jack initialization
  crypto: ablkcipher - fix crash flushing dcache in error path
  crypto: blkcipher - fix crash flushing dcache in error path
  crypto: vmac - separate tfm and request context
  crypto: vmac - require a block cipher with 128-bit block size
  kbuild: verify that $DEPMOD is installed
  i2c: ismt: fix wrong device address when unmap the data buffer
  kasan: don't emit builtin calls when sanitization is off
  tcp: Fix missing range_truesize enlargement in the backport
  x86/mm: Disable ioremap free page handling on x86-PAE
  Linux 4.4.148
  x86/speculation/l1tf: Unbreak !__HAVE_ARCH_PFN_MODIFY_ALLOWED architectures
  x86/init: fix build with CONFIG_SWAP=n
  x86/speculation/l1tf: Fix up CPU feature flags
  ...

Signed-off-by: Dan Murphy <dmurphy@ti.com>
# Conflicts:
# arch/arm64/include/asm/cputype.h
# arch/arm64/include/asm/memory.h
# arch/x86/Kconfig
# arch/x86/include/asm/thread_info.h

Merge branch 'ti-linux-4.4.y' of git.ti.com:ti-linux-kernel/ti-linux-kernel into ti-lsk-linux-4.4.y

TI-Feature: ti_linux_base_lsk
TI-Tree: git@git.ti.com:ti-linux-kernel/ti-linux-kernel.git
TI-Branch: ti-linux-4.4.y

* 'ti-linux-4.4.y' of git.ti.com:ti-linux-kernel/ti-linux-kernel: (2092 commits)
  Linux 4.4.141
  loop: remember whether sysfs_create_group() was done
  RDMA/ucm: Mark UCM interface as BROKEN
  PM / hibernate: Fix oops at snapshot_write()
  loop: add recursion validation to LOOP_CHANGE_FD
  netfilter: x_tables: initialise match/target check parameter struct
  netfilter: nf_queue: augment nfqa_cfg_policy
  uprobes/x86: Remove incorrect WARN_ON() in uprobe_init_insn()
  x86/cpufeature: Add helper macro for mask check macros
  x86/cpufeature: Make sure DISABLED/REQUIRED macros are updated
  x86/cpufeature: Update cpufeaure macros
  x86/cpufeature, x86/mm/pkeys: Fix broken compile-time disabling of pkeys
  x86/cpu: Add detection of AMD RAS Capabilities
  x86/mm/pkeys: Fix mismerge of protection keys CPUID bits
  x86/cpufeature, x86/mm/pkeys: Add protection keys related CPUID definitions
  x86/cpufeature: Speed up cpu_feature_enabled()
  x86/boot: Simplify kernel load address alignment check
  x86/vdso: Use static_cpu_has()
  x86/alternatives: Discard dynamic check after init
  x86/alternatives: Add an auxilary section
  ...

Signed-off-by: Dan Murphy <dmurphy@ti.com>
# Conflicts:
# arch/arm64/include/asm/assembler.h
# arch/arm64/include/asm/cputype.h
# arch/arm64/include/asm/memory.h
# arch/arm64/mm/mmu.c
# arch/x86/Kconfig

Merge tag 'v4.4.150' into linux-linaro-lsk-v4.4

This is the 4.4.150 stable release

Linux 4.4.150

x86/speculation/l1tf: Exempt zeroed PTEs from inversion

commit f19f5c49bbc3ffcc9126cc245fc1b24cc29f4a37 upstream.

It turns out that we should *not* invert all not-present mappings,
because the all zeroes case is obviously special.

clear_page() does not undergo the XOR logic to invert the address bits,
i.e. PTE, PMD and PUD entries that have not been individually written
will have val=0 and so will trigger __pte_needs_invert(). As a result,
{pte,pmd,pud}_pfn() will return the wrong PFN value, i.e. all ones
(adjusted by the max PFN mask) instead of zero. A zeroed entry is ok
because the page at physical address 0 is reserved early in boot
specifically to mitigate L1TF, so explicitly exempt them from the
inversion when reading the PFN.

Manifested as an unexpected mprotect(..., PROT_NONE) failure when called
on a VMA that has VM_PFNMAP and was mmap'd to as something other than
PROT_NONE but never used. mprotect() sends the PROT_NONE request down
prot_none_walk(), which walks the PTEs to check the PFNs.
prot_none_pte_entry() gets the bogus PFN from pte_pfn() and returns
-EACCES because it thinks mprotect() is trying to adjust a high MMIO
address.

[ This is a very modified version of Sean's original patch, but all
  credit goes to Sean for doing this and also pointing out that
  sometimes the __pte_needs_invert() function only gets the protection
  bits, not the full eventual pte.  But zero remains special even in
  just protection bits, so that's ok.   - Linus ]

Fixes: f22cc87f6c1f ("x86/speculation/l1tf: Invert all not present mappings")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Linux 4.4.149

x86/mm: Add TLB purge to free pmd/pte page interfaces

commit 5e0fb5df2ee871b841f96f9cb6a7f2784e96aa4e upstream.

ioremap() calls pud_free_pmd_page() / pmd_free_pte_page() when it creates
a pud / pmd map.  The following preconditions are met at their entry.
 - All pte entries for a target pud/pmd address range have been cleared.
 - System-wide TLB purges have been peformed for a target pud/pmd address
   range.

The preconditions assure that there is no stale TLB entry for the range.
Speculation may not cache TLB entries since it requires all levels of page
entries, including ptes, to have P & A-bits set for an associated address.
However, speculation may cache pud/pmd entries (paging-structure caches)
when they have P-bit set.

Add a system-wide TLB purge (INVLPG) to a single page after clearing
pud/pmd entry's P-bit.

SDM 4.10.4.1, Operation that Invalidate TLBs and Paging-Structure Caches,
states that:
  INVLPG invalidates all paging-structure caches associated with the
  current PCID regardless of the liner addresses to which they correspond.

Fixes: 28ee90fe6048 ("x86/mm: implement free pmd/pte page interfaces")
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: mhocko@suse.com
Cc: akpm@linux-foundation.org
Cc: hpa@zytor.com
Cc: cpandya@codeaurora.org
Cc: linux-mm@kvack.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: Joerg Roedel <joro@8bytes.org>
Cc: stable@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20180627141348.21777-4-toshi.kani@hpe.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ioremap: Update pgtable free interfaces with addr

commit 785a19f9d1dd8a4ab2d0633be4656653bd3de1fc upstream.

The following kernel panic was observed on ARM64 platform due to a stale
TLB entry.

 1. ioremap with 4K size, a valid pte page table is set.
 2. iounmap it, its pte entry is set to 0.
 3. ioremap the same address with 2M size, update its pmd entry with
    a new value.
 4. CPU may hit an exception because the old pmd entry is still in TLB,
    which leads to a kernel panic.

Commit b6bdb7517c3d ("mm/vmalloc: add interfaces to free unmapped page
table") has addressed this panic by falling to pte mappings in the above
case on ARM64.

To support pmd mappings in all cases, TLB purge needs to be performed
in this case on ARM64.

Add a new arg, 'addr', to pud_free_pmd_page() and pmd_free_pte_page()
so that TLB purge can be added later in seprate patches.

[toshi.kani@hpe.com: merge changes, rewrite patch description]
Fixes: 28ee90fe6048 ("x86/mm: implement free pmd/pte page interfaces")
Signed-off-by: Chintan Pandya <cpandya@codeaurora.org>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: mhocko@suse.com
Cc: akpm@linux-foundation.org
Cc: hpa@zytor.com
Cc: linux-mm@kvack.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: Will Deacon <will.deacon@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: stable@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20180627141348.21777-3-toshi.kani@hpe.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Bluetooth: hidp: buffer overflow in hidp_process_report

commit 7992c18810e568b95c869b227137a2215702a805 upstream.

CVE-2018-9363

The buffer length is unsigned at all layers, but gets cast to int and
checked in hidp_process_report and can lead to a buffer overflow.
Switch len parameter to unsigned int to resolve issue.

This affects 3.18 and newer kernels.

Signed-off-by: Mark Salyzyn <salyzyn@android.com>
Fixes: a4b1b5877b514b276f0f31efe02388a9c2836728 ("HID: Bluetooth: hidp: make sure input buffers are big enough")
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: Johan Hedberg <johan.hedberg@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: linux-bluetooth@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: security@kernel.org
Cc: kernel-team@android.com
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ASoC: Intel: cht_bsw_max98090_ti: Fix jack initialization

commit 3bbda5a38601f7675a214be2044e41d7749e6c7b upstream.

If the ts3a227e audio accessory detection hardware is present and its
driver probed, the jack needs to be created before enabling jack
detection in the ts3a227e driver. With this patch, the jack is
instantiated in the max98090 headset init function if the ts3a227e is
present. This fixes a null pointer dereference as the jack detection
enabling function in the ts3a driver was called before the jack is
created.

[minor correction to keep error handling on jack creation the same
as before by Pierre Bossart]

Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Acked-By: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

crypto: ablkcipher - fix crash flushing dcache in error path

commit 318abdfbe708aaaa652c79fb500e9bd60521f9dc upstream.

Like the skcipher_walk and blkcipher_walk cases:

scatterwalk_done() is only meant to be called after a nonzero number of
bytes have been processed, since scatterwalk_pagedone() will flush the
dcache of the *previous* page.  But in the error case of
ablkcipher_walk_done(), e.g. if the input wasn't an integer number of
blocks, scatterwalk_done() was actually called after advancing 0 bytes.
This caused a crash ("BUG: unable to handle kernel paging request")
during '!PageSlab(page)' on architectures like arm and arm64 that define
ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE, provided that the input was
page-aligned as in that case walk->offset == 0.

Fix it by reorganizing ablkcipher_walk_done() to skip the
scatterwalk_advance() and scatterwalk_done() if an error has occurred.

Reported-by: Liu Chao <liuchao741@huawei.com>
Fixes: bf06099db18a ("crypto: skcipher - Add ablkcipher_walk interfaces")
Cc: <stable@vger.kernel.org> # v2.6.35+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

crypto: blkcipher - fix crash flushing dcache in error path

commit 0868def3e4100591e7a1fdbf3eed1439cc8f7ca3 upstream.

Like the skcipher_walk case:

scatterwalk_done() is only meant to be called after a nonzero number of
bytes have been processed, since scatterwalk_pagedone() will flush the
dcache of the *previous* page.  But in the error case of
blkcipher_walk_done(), e.g. if the input wasn't an integer number of
blocks, scatterwalk_done() was actually called after advancing 0 bytes.
This caused a crash ("BUG: unable to handle kernel paging request")
during '!PageSlab(page)' on architectures like arm and arm64 that define
ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE, provided that the input was
page-aligned as in that case walk->offset == 0.

Fix it by reorganizing blkcipher_walk_done() to skip the
scatterwalk_advance() and scatterwalk_done() if an error has occurred.

This bug was found by syzkaller fuzzing.

Reproducer, assuming ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE:

#include <linux/if_alg.h>
#include <sys/socket.h>
#include <unistd.h>

int main()
{
struct sockaddr_alg addr = {
.salg_type = "skcipher",
.salg_name = "ecb(aes-generic)",
};
char buffer[4096] __attribute__((aligned(4096))) = { 0 };
int fd;

fd = socket(AF_ALG, SOCK_SEQPACKET, 0);
bind(fd, (void *)&addr, sizeof(addr));
setsockopt(fd, SOL_ALG, ALG_SET_KEY, buffer, 16);
fd = accept(fd, NULL, NULL);
write(fd, buffer, 15);
read(fd, buffer, 15);
}

Reported-by: Liu Chao <liuchao741@huawei.com>
Fixes: 5cde0af2a982 ("[CRYPTO] cipher: Added block cipher type")
Cc: <stable@vger.kernel.org> # v2.6.19+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

crypto: vmac - separate tfm and request context

commit bb29648102335586e9a66289a1d98a0cb392b6e5 upstream.

syzbot reported a crash in vmac_final() when multiple threads
concurrently use the same "vmac(aes)" transform through AF_ALG.  The bug
is pretty fundamental: the VMAC template doesn't separate per-request
state from per-tfm (per-key) state like the other hash algorithms do,
but rather stores it all in the tfm context.  That's wrong.

Also, vmac_final() incorrectly zeroes most of the state including the
derived keys and cached pseudorandom pad.  Therefore, only the first
VMAC invocation with a given key calculates the correct digest.

Fix these bugs by splitting the per-tfm state from the per-request state
and using the proper init/update/final sequencing for requests.

Reproducer for the crash:

    #include <linux/if_alg.h>
    #include <sys/socket.h>
    #include <unistd.h>

    int main()
    {
            int fd;
            struct sockaddr_alg addr = {
                    .salg_type = "hash",
                    .salg_name = "vmac(aes)",
            };
            char buf[256] = { 0 };

            fd = socket(AF_ALG, SOCK_SEQPACKET, 0);
            bind(fd, (void *)&addr, sizeof(addr));
            setsockopt(fd, SOL_ALG, ALG_SET_KEY, buf, 16);
            fork();
            fd = accept(fd, NULL, NULL);
            for (;;)
                    write(fd, buf, 256);
    }

The immediate cause of the crash is that vmac_ctx_t.partial_size exceeds
VMAC_NHBYTES, causing vmac_final() to memset() a negative length.

Reported-by: syzbot+264bca3a6e8d645550d3@syzkaller.appspotmail.com
Fixes: f1939f7c5645 ("crypto: vmac - New hash algorithm for intel_txt support")
Cc: <stable@vger.kernel.org> # v2.6.32+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

crypto: vmac - require a block cipher with 128-bit block size

commit 73bf20ef3df262026c3470241ae4ac8196943ffa upstream.

The VMAC template assumes the block cipher has a 128-bit block size, but
it failed to check for that.  Thus it was possible to instantiate it
using a 64-bit block size cipher, e.g. "vmac(cast5)", causing
uninitialized memory to be used.

Add the needed check when instantiating the template.

Fixes: f1939f7c5645 ("crypto: vmac - New hash algorithm for intel_txt support")
Cc: <stable@vger.kernel.org> # v2.6.32+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kbuild: verify that $DEPMOD is installed

commit 934193a654c1f4d0643ddbf4b2529b508cae926e upstream.

Verify that 'depmod' ($DEPMOD) is installed.
This is a partial revert of commit 620c231c7a7f
("kbuild: do not check for ancient modutils tools").

Also update Documentation/process/changes.rst to refer to
kmod instead of module-init-tools.

Fixes kernel bugzilla #198965:
https://bugzilla.kernel.org/show_bug.cgi?id=198965

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Lucas De Marchi <lucas.demarchi@profusion.mobi>
Cc: Lucas De Marchi <lucas.de.marchi@gmail.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Chih-Wei Huang <cwhuang@linux.org.tw>
Cc: stable@vger.kernel.org # any kernel since 2012
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

i2c: ismt: fix wrong device address when unmap the data buffer

commit 17e83549e199d89aace7788a9f11c108671eecf5 upstream.

Fix the following kernel bug:

kernel BUG at drivers/iommu/intel-iommu.c:3260!
invalid opcode: 0000 [#5] PREEMPT SMP
Hardware name: Intel Corp. Harcuvar/Server, BIOS HAVLCRB0.X64.0013.D39.1608311820 08/31/2016
task: ffff880175389950 ti: ffff880176bec000 task.ti: ffff880176bec000
RIP: 0010:[<ffffffff8150a83b>]  [<ffffffff8150a83b>] intel_unmap+0x25b/0x260
RSP: 0018:ffff880176bef5e8  EFLAGS: 00010296
RAX: 0000000000000024 RBX: ffff8800773c7c88 RCX: 000000000000ce04
RDX: 0000000080000000 RSI: 0000000000000000 RDI: 0000000000000009
RBP: ffff880176bef638 R08: 0000000000000010 R09: 0000000000000004
R10: ffff880175389c78 R11: 0000000000000a4f R12: ffff8800773c7868
R13: 00000000ffffac88 R14: ffff8800773c7818 R15: 0000000000000001
FS:  00007fef21258700(0000) GS:ffff88017b5c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000066d6d8 CR3: 000000007118c000 CR4: 00000000003406e0
Stack:
 00000000ffffac88 ffffffff8199867f ffff880176bef5f8 ffff880100000030
 ffff880176bef668 ffff8800773c7c88 ffff880178288098 ffff8800772c0010
 ffff8800773c7818 0000000000000001 ffff880176bef648 ffffffff8150a86e
Call Trace:
 [<ffffffff8199867f>] ? printk+0x46/0x48
 [<ffffffff8150a86e>] intel_unmap_page+0xe/0x10
 [<ffffffffa039d99b>] ismt_access+0x27b/0x8fa [i2c_ismt]
 [<ffffffff81554420>] ? __pm_runtime_suspend+0xa0/0xa0
 [<ffffffff815544a0>] ? pm_suspend_timer_fn+0x80/0x80
 [<ffffffff81554420>] ? __pm_runtime_suspend+0xa0/0xa0
 [<ffffffff815544a0>] ? pm_suspend_timer_fn+0x80/0x80
 [<ffffffff8143dfd0>] ? pci_bus_read_dev_vendor_id+0xf0/0xf0
 [<ffffffff8172b36c>] i2c_smbus_xfer+0xec/0x4b0
 [<ffffffff810aa4d5>] ? vprintk_emit+0x345/0x530
 [<ffffffffa038936b>] i2cdev_ioctl_smbus+0x12b/0x240 [i2c_dev]
 [<ffffffff810aa829>] ? vprintk_default+0x29/0x40
 [<ffffffffa0389b33>] i2cdev_ioctl+0x63/0x1ec [i2c_dev]
 [<ffffffff811b04c8>] do_vfs_ioctl+0x328/0x5d0
 [<ffffffff8119d8ec>] ? vfs_write+0x11c/0x190
 [<ffffffff8109d449>] ? rt_up_read+0x19/0x20
 [<ffffffff811b07f1>] SyS_ioctl+0x81/0xa0
 [<ffffffff819a351b>] system_call_fastpath+0x16/0x6e

This happen When run "i2cdetect -y 0" detect SMBus iSMT adapter.

After finished I2C block read/write, when unmap the data buffer,
a wrong device address was pass to dma_unmap_single().

To fix this, give dma_unmap_single() the "dev" parameter, just like
what dma_map_single() does, then unmap can find the right devices.

Fixes: 13f35ac14cd0 ("i2c: Adding support for Intel iSMT SMBus 2.0 host controller")
Signed-off-by: Liwei Song <liwei.song@windriver.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kasan: don't emit builtin calls when sanitization is off

commit 0e410e158e5baa1300bdf678cea4f4e0cf9d8b94 upstream.

With KASAN enabled the kernel has two different memset() functions, one
with KASAN checks (memset) and one without (__memset).  KASAN uses some
macro tricks to use the proper version where required.  For example
memset() calls in mm/slub.c are without KASAN checks, since they operate
on poisoned slab object metadata.

The issue is that clang emits memset() calls even when there is no
memset() in the source code.  They get linked with improper memset()
implementation and the kernel fails to boot due to a huge amount of KASAN
reports during early boot stages.

The solution is to add -fno-builtin flag for files with KASAN_SANITIZE :=
n marker.

Link: http://lkml.kernel.org/r/8ffecfffe04088c52c42b92739c2bd8a0bcb3f5e.1516384594.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ Nick : Backported to 4.4 avoiding KUBSAN ]
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tcp: Fix missing range_truesize enlargement in the backport

The 4.4.y stable backport dc6ae4dffd65 for the upstream commit
3d4bf93ac120 ("tcp: detect malicious patterns in
tcp_collapse_ofo_queue()") missed a line that enlarges the
range_truesize value, which broke the whole check.

Fixes: dc6ae4dffd65 ("tcp: detect malicious patterns in tcp_collapse_ofo_queue()")
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: Michal Kubecek <mkubecek@suse.cz>

x86/mm: Disable ioremap free page handling on x86-PAE

commit f967db0b9ed44ec3057a28f3b28efc51df51b835 upstream.

ioremap() supports pmd mappings on x86-PAE.  However, kernel's pmd
tables are not shared among processes on x86-PAE.  Therefore, any
update to sync'd pmd entries need re-syncing.  Freeing a pte page
also leads to a vmalloc fault and hits the BUG_ON in vmalloc_sync_one().

Disable free page handling on x86-PAE.  pud_free_pmd_page() and
pmd_free_pte_page() simply return 0 if a given pud/pmd entry is present.
This assures that ioremap() does not update sync'd pmd entries at the
cost of falling back to pte mappings.

Fixes: 28ee90fe6048 ("x86/mm: implement free pmd/pte page interfaces")
Reported-by: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: mhocko@suse.com
Cc: akpm@linux-foundation.org
Cc: hpa@zytor.com
Cc: cpandya@codeaurora.org
Cc: linux-mm@kvack.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: stable@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20180627141348.21777-2-toshi.kani@hpe.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge tag 'v4.4.148' into linux-linaro-lsk-v4.4

This is the 4.4.148 stable release

Linux 4.4.148

x86/speculation/l1tf: Unbreak !__HAVE_ARCH_PFN_MODIFY_ALLOWED architectures

commit 6c26fcd2abfe0a56bbd95271fce02df2896cfd24 upstream.

pfn_modify_allowed() and arch_has_pfn_modify_check() are outside of the
!__ASSEMBLY__ section in include/asm-generic/pgtable.h, which confuses
assembler on archs that don't have __HAVE_ARCH_PFN_MODIFY_ALLOWED (e.g.
ia64) and breaks build:

    include/asm-generic/pgtable.h: Assembler messages:
    include/asm-generic/pgtable.h:538: Error: Unknown opcode `static inline bool pfn_modify_allowed(unsigned long pfn,pgprot_t prot)'
    include/asm-generic/pgtable.h:540: Error: Unknown opcode `return true'
    include/asm-generic/pgtable.h:543: Error: Unknown opcode `static inline bool arch_has_pfn_modify_check(void)'
    include/asm-generic/pgtable.h:545: Error: Unknown opcode `return false'
    arch/ia64/kernel/entry.S:69: Error: `mov' does not fit into bundle

Move those two static inlines into the !__ASSEMBLY__ section so that they
don't confuse the asm build pass.

Fixes: 42e4089c7890 ("x86/speculation/l1tf: Disallow non privileged high MMIO PROT_NONE mappings")
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[groeck: Context changes]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

x86/init: fix build with CONFIG_SWAP=n

commit 792adb90fa724ce07c0171cbc96b9215af4b1045 upstream.

The introduction of generic_max_swapfile_size and arch-specific versions has
broken linking on x86 with CONFIG_SWAP=n due to undefined reference to
'generic_max_swapfile_size'. Fix it by compiling the x86-specific
max_swapfile_size() only with CONFIG_SWAP=y.

Reported-by: Tomas Pruzina <pruzinat@gmail.com>
Fixes: 377eeaa8e11f ("x86/speculation/l1tf: Limit swap file size to MAX_PA/2")
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Fix up CPU feature flags

In linux-4.4.y, the definition of X86_FEATURE_RETPOLINE and
X86_FEATURE_RETPOLINE_AMD is different from the upstream
definition. Result is an overlap with the newly introduced
X86_FEATURE_L1TF_PTEINV. Update RETPOLINE definitions to match
upstream definitions to improve alignment with upstream code.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/mm/kmmio: Make the tracer robust against L1TF

commit 1063711b57393c1999248cccb57bebfaf16739e7 upstream

The mmio tracer sets io mapping PTEs and PMDs to non present when enabled
without inverting the address bits, which makes the PTE entry vulnerable
for L1TF.

Make it use the right low level macros to actually invert the address bits
to protect against L1TF.

In principle this could be avoided because MMIO tracing is not likely to be
enabled on production machines, but the fix is straigt forward and for
consistency sake it's better to get rid of the open coded PTE manipulation.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/mm/pat: Make set_memory_np() L1TF safe

commit 958f79b9ee55dfaf00c8106ed1c22a2919e0028b upstream

set_memory_np() is used to mark kernel mappings not present, but it has
it's own open coded mechanism which does not have the L1TF protection of
inverting the address bits.

Replace the open coded PTE manipulation with the L1TF protecting low level
PTE routines.

Passes the CPA self test.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[ dwmw2: Pull in pud_mkhuge() from commit a00cc7d9dd, and pfn_pud() ]
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[groeck: port to 4.4]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Make pmd/pud_mknotpresent() invert

commit 0768f91530ff46683e0b372df14fd79fe8d156e5 upstream

Some cases in THP like:
  - MADV_FREE
  - mprotect
  - split

mark the PMD non present for temporarily to prevent races. The window for
an L1TF attack in these contexts is very small, but it wants to be fixed
for correctness sake.

Use the proper low level functions for pmd/pud_mknotpresent() to address
this.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Invert all not present mappings

commit f22cc87f6c1f771b57c407555cfefd811cdd9507 upstream

For kernel mappings PAGE_PROTNONE is not necessarily set for a non present
mapping, but the inversion logic explicitely checks for !PRESENT and
PROT_NONE.

Remove the PROT_NONE check and make the inversion unconditional for all not
present mappings.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Fix up pte->pfn conversion for PAE

commit e14d7dfb41f5807a0c1c26a13f2b8ef16af24935 upstream

Jan has noticed that pte_pfn and co. resp. pfn_pte are incorrect for
CONFIG_PAE because phys_addr_t is wider than unsigned long and so the
pte_val reps. shift left would get truncated. Fix this up by using proper
types.

[dwmw2: Backport to 4.9]

Fixes: 6b28baca9b1f ("x86/speculation/l1tf: Protect PROT_NONE PTEs against speculation")
Reported-by: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Protect PAE swap entries against L1TF

commit 0d0f6249058834ffe1ceaad0bb31464af66f6e7a upstream

The PAE 3-level paging code currently doesn't mitigate L1TF by flipping the
offset bits, and uses the high PTE word, thus bits 32-36 for type, 37-63 for
offset. The lower word is zeroed, thus systems with less than 4GB memory are
safe. With 4GB to 128GB the swap type selects the memory locations vulnerable
to L1TF; with even more memory, also the swap offfset influences the address.
This might be a problem with 32bit PAE guests running on large 64bit hosts.

By continuing to keep the whole swap entry in either high or low 32bit word of
PTE we would limit the swap size too much. Thus this patch uses the whole PAE
PTE with the same layout as the 64bit version does. The macros just become a
bit tricky since they assume the arch-dependent swp_entry_t to be 32bit.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/cpufeatures: Add detection of L1D cache flush support.

commit 11e34e64e4103955fc4568750914c75d65ea87ee upstream

336996-Speculative-Execution-Side-Channel-Mitigations.pdf defines a new MSR
(IA32_FLUSH_CMD) which is detected by CPUID.7.EDX[28]=1 bit being set.

This new MSR "gives software a way to invalidate structures with finer
granularity than other architectual methods like WBINVD."

A copy of this document is available at
  https://bugzilla.kernel.org/show_bug.cgi?id=199511

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Extend 64bit swap file size limit

commit 1a7ed1ba4bba6c075d5ad61bb75e3fbc870840d6 upstream

The previous patch has limited swap file size so that large offsets cannot
clear bits above MAX_PA/2 in the pte and interfere with L1TF mitigation.

It assumed that offsets are encoded starting with bit 12, same as pfn. But
on x86_64, offsets are encoded starting with bit 9.

Thus the limit can be raised by 3 bits. That means 16TB with 42bit MAX_PA
and 256TB with 46bit MAX_PA.

Fixes: 377eeaa8e11f ("x86/speculation/l1tf: Limit swap file size to MAX_PA/2")
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/bugs: Move the l1tf function and define pr_fmt properly

commit 56563f53d3066afa9e63d6c997bf67e76a8b05c0 upstream

The pr_warn in l1tf_select_mitigation would have used the prior pr_fmt
which was defined as "Spectre V2 : ".

Move the function to be past SSBD and also define the pr_fmt.

Fixes: 17dbca119312 ("x86/speculation/l1tf: Add sysfs reporting for l1tf")
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Limit swap file size to MAX_PA/2

commit 377eeaa8e11fe815b1d07c81c4a0e2843a8c15eb upstream

For the L1TF workaround its necessary to limit the swap file size to below
MAX_PA/2, so that the higher bits of the swap offset inverted never point
to valid memory.

Add a mechanism for the architecture to override the swap file size check
in swapfile.c and add a x86 specific max swapfile check function that
enforces that limit.

The check is only enabled if the CPU is vulnerable to L1TF.

In VMs with 42bit MAX_PA the typical limit is 2TB now, on a native system
with 46bit PA it is 32TB. The limit is only per individual swap file, so
it's always possible to exceed these limits with multiple swap files or
partitions.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Disallow non privileged high MMIO PROT_NONE mappings

commit 42e4089c7890725fcd329999252dc489b72f2921 upstream

For L1TF PROT_NONE mappings are protected by inverting the PFN in the page
table entry. This sets the high bits in the CPU's address space, thus
making sure to point to not point an unmapped entry to valid cached memory.

Some server system BIOSes put the MMIO mappings high up in the physical
address space. If such an high mapping was mapped to unprivileged users
they could attack low memory by setting such a mapping to PROT_NONE. This
could happen through a special device driver which is not access
protected. Normal /dev/mem is of course access protected.

To avoid this forbid PROT_NONE mappings or mprotect for high MMIO mappings.

Valid page mappings are allowed because the system is then unsafe anyways.

It's not expected that users commonly use PROT_NONE on MMIO. But to
minimize any impact this is only enforced if the mapping actually refers to
a high MMIO address (defined as the MAX_PA-1 bit being set), and also skip
the check for root.

For mmaps this is straight forward and can be handled in vm_insert_pfn and
in remap_pfn_range().

For mprotect it's a bit trickier. At the point where the actual PTEs are
accessed a lot of state has been changed and it would be difficult to undo
on an error. Since this is a uncommon case use a separate early page talk
walk pass for MMIO PROT_NONE mappings that checks for this condition
early. For non MMIO and non PROT_NONE there are no changes.

[dwmw2: Backport to 4.9]
[groeck: Backport to 4.4]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mm: fix cache mode tracking in vm_insert_mixed()

commit 87744ab3832b83ba71b931f86f9cfdb000d07da5 upstream

vm_insert_mixed() unlike vm_insert_pfn_prot() and vmf_insert_pfn_pmd(),
fails to check the pgprot_t it uses for the mapping against the one
recorded in the memtype tracking tree.  Add the missing call to
track_pfn_insert() to preclude cases where incompatible aliased mappings
are established for a given physical address range.

[groeck: Backport to v4.4.y]

Link: http://lkml.kernel.org/r/147328717909.35069.14256589123570653697.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mm: Add vm_insert_pfn_prot()

commit 1745cbc5d0dee0749a6bc0ea8e872c5db0074061 upstream

The x86 vvar vma contains pages with differing cacheability
flags.  x86 currently implements this by manually inserting all
the ptes using (io_)remap_pfn_range when the vma is set up.

x86 wants to move to using .fault with VM_FAULT_NOPAGE to set up
the mappings as needed.  The correct API to use to insert a pfn
in .fault is vm_insert_pfn(), but vm_insert_pfn() can't override the
vma's cache mode, and the HPET page in particular needs to be
uncached despite the fact that the rest of the VMA is cached.

Add vm_insert_pfn_prot() to support varying cacheability within
the same non-COW VMA in a more sane manner.

x86 could alternatively use multiple VMAs, but that's messy,
would break CRIU, and would create unnecessary VMAs that would
waste memory.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/d2938d1eb37be7a5e4f86182db646551f11e45aa.1451446564.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Add sysfs reporting for l1tf

commit 17dbca119312b4e8173d4e25ff64262119fcef38 upstream

L1TF core kernel workarounds are cheap and normally always enabled, However
they still should be reported in sysfs if the system is vulnerable or
mitigated. Add the necessary CPU feature/bug bits.

- Extend the existing checks for Meltdowns to determine if the system is
  vulnerable. All CPUs which are not vulnerable to Meltdown are also not
  vulnerable to L1TF

- Check for 32bit non PAE and emit a warning as there is no practical way
  for mitigation due to the limited physical address bits

- If the system has more than MAX_PA/2 physical memory the invert page
  workarounds don't protect the system against the L1TF attack anymore,
  because an inverted physical address will also point to valid
  memory. Print a warning in this case and report that the system is
  vulnerable.

Add a function which returns the PFN limit for the L1TF mitigation, which
will be used in follow up patches for sanity and range checks.

[ tglx: Renamed the CPU feature bit to L1TF_PTEINV ]
[ dwmw2: Backport to 4.9 (cpufeatures.h, E820) ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Make sure the first page is always reserved

commit 10a70416e1f067f6c4efda6ffd8ea96002ac4223 upstream

The L1TF workaround doesn't make any attempt to mitigate speculate accesses
to the first physical page for zeroed PTEs. Normally it only contains some
data from the early real mode BIOS.

It's not entirely clear that the first page is reserved in all
configurations, so add an extra reservation call to make sure it is really
reserved. In most configurations (e.g.  with the standard reservations)
it's likely a nop.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Protect PROT_NONE PTEs against speculation

commit 6b28baca9b1f0d4a42b865da7a05b1c81424bd5c upstream

When PTEs are set to PROT_NONE the kernel just clears the Present bit and
preserves the PFN, which creates attack surface for L1TF speculation
speculation attacks.

This is important inside guests, because L1TF speculation bypasses physical
page remapping. While the host has its own migitations preventing leaking
data from other VMs into the guest, this would still risk leaking the wrong
page inside the current guest.

This uses the same technique as Linus' swap entry patch: while an entry is
is in PROTNONE state invert the complete PFN part part of it. This ensures
that the the highest bit will point to non existing memory.

The invert is done by pte/pmd_modify and pfn/pmd/pud_pte for PROTNONE and
pte/pmd/pud_pfn undo it.

This assume that no code path touches the PFN part of a PTE directly
without using these primitives.

This doesn't handle the case that MMIO is on the top of the CPU physical
memory. If such an MMIO region was exposed by an unpriviledged driver for
mmap it would be possible to attack some real memory.  However this
situation is all rather unlikely.

For 32bit non PAE the inversion is not done because there are really not
enough bits to protect anything.

Q: Why does the guest need to be protected when the HyperVisor already has
   L1TF mitigations?

A: Here's an example:

   Physical pages 1 2 get mapped into a guest as
   GPA 1 -> PA 2
   GPA 2 -> PA 1
   through EPT.

   The L1TF speculation ignores the EPT remapping.

   Now the guest kernel maps GPA 1 to process A and GPA 2 to process B, and
   they belong to different users and should be isolated.

   A sets the GPA 1 PA 2 PTE to PROT_NONE to bypass the EPT remapping and
   gets read access to the underlying physical page. Which in this case
   points to PA 2, so it can read process B's data, if it happened to be in
   L1, so isolation inside the guest is broken.

   There's nothing the hypervisor can do about this. This mitigation has to
   be done in the guest itself.

[ tglx: Massaged changelog ]
[ dwmw2: backported to 4.9 ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Protect swap entries against L1TF

commit 2f22b4cd45b67b3496f4aa4c7180a1271c6452f6 upstream

With L1 terminal fault the CPU speculates into unmapped PTEs, and resulting
side effects allow to read the memory the PTE is pointing too, if its
values are still in the L1 cache.

For swapped out pages Linux uses unmapped PTEs and stores a swap entry into
them.

To protect against L1TF it must be ensured that the swap entry is not
pointing to valid memory, which requires setting higher bits (between bit
36 and bit 45) that are inside the CPUs physical address space, but outside
any real memory.

To do this invert the offset to make sure the higher bits are always set,
as long as the swap file is not too big.

Note there is no workaround for 32bit !PAE, or on systems which have more
than MAX_PA/2 worth of memory. The later case is very unlikely to happen on
real systems.

[AK: updated description and minor tweaks by. Split out from the original
     patch ]

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Change order of offset/type in swap entry

commit bcd11afa7adad8d720e7ba5ef58bdcd9775cf45f upstream

If pages are swapped out, the swap entry is stored in the corresponding
PTE, which has the Present bit cleared. CPUs vulnerable to L1TF speculate
on PTE entries which have the present bit set and would treat the swap
entry as phsyical address (PFN). To mitigate that the upper bits of the PTE
must be set so the PTE points to non existent memory.

The swap entry stores the type and the offset of a swapped out page in the
PTE. type is stored in bit 9-13 and offset in bit 14-63. The hardware
ignores the bits beyond the phsyical address space limit, so to make the
mitigation effective its required to start 'offset' at the lowest possible
bit so that even large swap offsets do not reach into the physical address
space limit bits.

Move offset to bit 9-58 and type to bit 59-63 which are the bits that
hardware generally doesn't care about.

That, in turn, means that if you on desktop chip with only 40 bits of
physical addressing, now that the offset starts at bit 9, there needs to be
30 bits of offset actually *in use* until bit 39 ends up being set, which
means when inverted it will again point into existing memory.

So that's 4 terabyte of swap space (because the offset is counted in pages,
so 30 bits of offset is 42 bits of actual coverage). With bigger physical
addressing, that obviously grows further, until the limit of the offset is
hit (at 50 bits of offset - 62 bits of actual swap file coverage).

This is a preparatory change for the actual swap entry inversion to protect
against L1TF.

[ AK: Updated description and minor tweaks. Split into two parts ]
[ tglx: Massaged changelog ]

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mm: x86: move _PAGE_SWP_SOFT_DIRTY from bit 7 to bit 1

commit eee4818baac0f2b37848fdf90e4b16430dc536ac upstream

_PAGE_PSE is used to distinguish between a truly non-present
(_PAGE_PRESENT=0) PMD, and a PMD which is undergoing a THP split and
should be treated as present.

But _PAGE_SWP_SOFT_DIRTY currently uses the _PAGE_PSE bit, which would
cause confusion between one of those PMDs undergoing a THP split, and a
soft-dirty PMD.  Dropping _PAGE_PSE check in pmd_present() does not work
well, because it can hurt optimization of tlb handling in thp split.

Thus, we need to move the bit.

In the current kernel, bits 1-4 are not used in non-present format since
commit 00839ee3b299 ("x86/mm: Move swap offset/type up in PTE to work
around erratum").  So let's move _PAGE_SWP_SOFT_DIRTY to bit 1.  Bit 7
is used as reserved (always clear), so please don't use it for other
purpose.

[dwmw2: Pulled in to 4.9 backport to support L1TF changes]

Link: http://lkml.kernel.org/r/20170717193955.20207-3-zi.yan@sent.com
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Zi Yan <zi.yan@cs.rutgers.edu>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: David Nellans <dnellans@nvidia.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/mm: Fix swap entry comment and macro

commit ace7fab7a6cdd363a615ec537f2aa94dbc761ee2 upstream

A recent patch changed the format of a swap PTE.

The comment explaining the format of the swap PTE is wrong about
the bits used for the swap type field.  Amusingly, the ASCII art
and the patch description are correct, but the comment itself
is wrong.

As I was looking at this, I also noticed that the
SWP_OFFSET_FIRST_BIT has an off-by-one error.  This does not
really hurt anything.  It just wasted a bit of space in the PTE,
giving us 2^59 bytes of addressable space in our swapfiles
instead of 2^60.  But, it doesn't match with the comments, and it
wastes a bit of space, so fix it.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Fixes: 00839ee3b299 ("x86/mm: Move swap offset/type up in PTE to work around erratum")
Link: http://lkml.kernel.org/r/20160810172325.E56AD7DA@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/mm: Move swap offset/type up in PTE to work around erratum

commit 00839ee3b299303c6a5e26a0a2485427a3afcbbf upstream

This erratum can result in Accessed/Dirty getting set by the hardware
when we do not expect them to be (on !Present PTEs).

Instead of trying to fix them up after this happens, we just
allow the bits to get set and try to ignore them.  We do this by
shifting the layout of the bits we use for swap offset/type in
our 64-bit PTEs.

It looks like this:

 bitnrs: |     ...            | 11| 10|  9|8|7|6|5| 4| 3|2|1|0|
 names:  |     ...            |SW3|SW2|SW1|G|L|D|A|CD|WT|U|W|P|
 before: |         OFFSET (9-63)          |0|X|X| TYPE(1-5) |0|
  after: | OFFSET (14-63)  |  TYPE (9-13) |0|X|X|X| X| X|X|X|0|

Note that D was already a don't care (X) even before.  We just
move TYPE up and turn its old spot (which could be hit by the
A bit) into all don't cares.

We take 5 bits away from the offset, but that still leaves us
with 50 bits which lets us index into a 62-bit swapfile (4 EiB).
I think that's probably fine for the moment.  We could
theoretically reclaim 5 of the bits (1, 2, 3, 4, 7) but it
doesn't gain us anything.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: dave.hansen@intel.com
Cc: linux-mm@kvack.org
Cc: mhocko@suse.com
Link: http://lkml.kernel.org/r/20160708001911.9A3FD2B6@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation/l1tf: Increase 32bit PAE __PHYSICAL_PAGE_SHIFT

commit 50896e180c6aa3a9c61a26ced99e15d602666a4c upstream

L1 Terminal Fault (L1TF) is a speculation related vulnerability. The CPU
speculates on PTE entries which do not have the PRESENT bit set, if the
content of the resulting physical address is available in the L1D cache.

The OS side mitigation makes sure that a !PRESENT PTE entry points to a
physical address outside the actually existing and cachable memory
space. This is achieved by inverting the upper bits of the PTE. Due to the
address space limitations this only works for 64bit and 32bit PAE kernels,
but not for 32bit non PAE.

This mitigation applies to both host and guest kernels, but in case of a
64bit host (hypervisor) and a 32bit PAE guest, inverting the upper bits of
the PAE address space (44bit) is not enough if the host has more than 43
bits of populated memory address space, because the speculation treats the
PTE content as a physical host address bypassing EPT.

The host (hypervisor) protects itself against the guest by flushing L1D as
needed, but pages inside the guest are not protected against attacks from
other processes inside the same guest.

For the guest the inverted PTE mask has to match the host to provide the
full protection for all pages the host could possibly map into the
guest. The hosts populated address space is not known to the guest, so the
mask must cover the possible maximal host address space, i.e. 52 bit.

On 32bit PAE the maximum PTE mask is currently set to 44 bit because that
is the limit imposed by 32bit unsigned long PFNs in the VMs. This limits
the mask to be below what the host could possible use for physical pages.

The L1TF PROT_NONE protection code uses the PTE masks to determine which
bits to invert to make sure the higher bits are set for unmapped entries to
prevent L1TF speculation attacks against EPT inside guests.

In order to invert all bits that could be used by the host, increase
__PHYSICAL_PAGE_SHIFT to 52 to match 64bit.

The real limit for a 32bit PAE kernel is still 44 bits because all Linux
PTEs are created from unsigned long PFNs, so they cannot be higher than 44
bits on a 32bit kernel. So these extra PFN bits should be never set. The
only users of this macro are using it to look at PTEs, so it's safe.

[ tglx: Massaged changelog ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/irqflags: Provide a declaration for native_save_fl

commit 208cbb32558907f68b3b2a081ca2337ac3744794 upstream.

It was reported that the commit d0a8d9378d16 is causing users of gcc < 4.9
to observe -Werror=missing-prototypes errors.

Indeed, it seems that:
extern inline unsigned long native_save_fl(void) { return 0; }

compiled with -Werror=missing-prototypes produces this warning in gcc <
4.9, but not gcc >= 4.9.

Fixes: d0a8d9378d16 ("x86/paravirt: Make native_save_fl() extern inline").
Reported-by: David Laight <david.laight@aculab.com>
Reported-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: hpa@zytor.com
Cc: jgross@suse.com
Cc: kstewart@linuxfoundation.org
Cc: gregkh@linuxfoundation.org
Cc: boris.ostrovsky@oracle.com
Cc: astrachan@google.com
Cc: mka@chromium.org
Cc: arnd@arndb.de
Cc: tstellar@redhat.com
Cc: sedat.dilek@gmail.com
Cc: David.Laight@aculab.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180803170550.164688-1-ndesaulniers@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kprobes/x86: Fix %p uses in error messages

commit 0ea063306eecf300fcf06d2f5917474b580f666f upstream.

Remove all %p uses in error messages in kprobes/x86.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Howells <dhowells@redhat.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jon Medhurst <tixy@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Tobin C . Harding <me@tobin.cc>
Cc: Will Deacon <will.deacon@arm.com>
Cc: acme@kernel.org
Cc: akpm@linux-foundation.org
Cc: brueckner@linux.vnet.ibm.com
Cc: linux-arch@vger.kernel.org
Cc: rostedt@goodmis.org
Cc: schwidefsky@de.ibm.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/lkml/152491902310.9916.13355297638917767319.stgit@devbox
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/speculation: Protect against userspace-userspace spectreRSB

commit fdf82a7856b32d905c39afc85e34364491e46346 upstream.

The article "Spectre Returns! Speculation Attacks using the Return Stack
Buffer" [1] describes two new (sub-)variants of spectrev2-like attacks,
making use solely of the RSB contents even on CPUs that don't fallback to
BTB on RSB underflow (Skylake+).

Mitigate userspace-userspace attacks by always unconditionally filling RSB on
context switch when the generic spectrev2 mitigation has been enabled.

[1] https://arxiv.org/pdf/1807.07940.pdf

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/nycvar.YFH.7.76.1807261308190.997@cbobk.fhfr.pm
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/paravirt: Fix spectre-v2 mitigations for paravirt guests

commit 5800dc5c19f34e6e03b5adab1282535cb102fafd upstream.

Nadav reported that on guests we're failing to rewrite the indirect
calls to CALLEE_SAVE paravirt functions. In particular the
pv_queued_spin_unlock() call is left unpatched and that is all over the
place. This obviously wrecks Spectre-v2 mitigation (for paravirt
guests) which relies on not actually having indirect calls around.

The reason is an incorrect clobber test in paravirt_patch_call(); this
function rewrites an indirect call with a direct call to the _SAME_
function, there is no possible way the clobbers can be different
because of this.

Therefore remove this clobber check. Also put WARNs on the other patch
failure case (not enough room for the instruction) which I've not seen
trigger in my (limited) testing.

Three live kernel image disassemblies for lock_sock_nested (as a small
function that illustrates the problem nicely). PRE is the current
situation for guests, POST is with this patch applied and NATIVE is with
or without the patch for !guests.

PRE:

(gdb) disassemble lock_sock_nested
Dump of assembler code for function lock_sock_nested:
   0xffffffff817be970 <+0>:     push   %rbp
   0xffffffff817be971 <+1>:     mov    %rdi,%rbp
   0xffffffff817be974 <+4>:     push   %rbx
   0xffffffff817be975 <+5>:     lea    0x88(%rbp),%rbx
   0xffffffff817be97c <+12>:    callq  0xffffffff819f7160 <_cond_resched>
   0xffffffff817be981 <+17>:    mov    %rbx,%rdi
   0xffffffff817be984 <+20>:    callq  0xffffffff819fbb00 <_raw_spin_lock_bh>
   0xffffffff817be989 <+25>:    mov    0x8c(%rbp),%eax
   0xffffffff817be98f <+31>:    test   %eax,%eax
   0xffffffff817be991 <+33>:    jne    0xffffffff817be9ba <lock_sock_nested+74>
   0xffffffff817be993 <+35>:    movl   $0x1,0x8c(%rbp)
   0xffffffff817be99d <+45>:    mov    %rbx,%rdi
   0xffffffff817be9a0 <+48>:    callq  *0xffffffff822299e8
   0xffffffff817be9a7 <+55>:    pop    %rbx
   0xffffffff817be9a8 <+56>:    pop    %rbp
   0xffffffff817be9a9 <+57>:    mov    $0x200,%esi
   0xffffffff817be9ae <+62>:    mov    $0xffffffff817be993,%rdi
   0xffffffff817be9b5 <+69>:    jmpq   0xffffffff81063ae0 <__local_bh_enable_ip>
   0xffffffff817be9ba <+74>:    mov    %rbp,%rdi
   0xffffffff817be9bd <+77>:    callq  0xffffffff817be8c0 <__lock_sock>
   0xffffffff817be9c2 <+82>:    jmp    0xffffffff817be993 <lock_sock_nested+35>
End of assembler dump.

POST:

(gdb) disassemble lock_sock_nested
Dump of assembler code for function lock_sock_nested:
   0xffffffff817be970 <+0>:     push   %rbp
   0xffffffff817be971 <+1>:     mov    %rdi,%rbp
   0xffffffff817be974 <+4>:     push   %rbx
   0xffffffff817be975 <+5>:     lea    0x88(%rbp),%rbx
   0xffffffff817be97c <+12>:    callq  0xffffffff819f7160 <_cond_resched>
   0xffffffff817be981 <+17>:    mov    %rbx,%rdi
   0xffffffff817be984 <+20>:    callq  0xffffffff819fbb00 <_raw_spin_lock_bh>
   0xffffffff817be989 <+25>:    mov    0x8c(%rbp),%eax
   0xffffffff817be98f <+31>:    test   %eax,%eax
   0xffffffff817be991 <+33>:    jne    0xffffffff817be9ba <lock_sock_nested+74>
   0xffffffff817be993 <+35>:    movl   $0x1,0x8c(%rbp)
   0xffffffff817be99d <+45>:    mov    %rbx,%rdi
   0xffffffff817be9a0 <+48>:    callq  0xffffffff810a0c20 <__raw_callee_save___pv_queued_spin_unlock>
   0xffffffff817be9a5 <+53>:    xchg   %ax,%ax
   0xffffffff817be9a7 <+55>:    pop    %rbx
   0xffffffff817be9a8 <+56>:    pop    %rbp
   0xffffffff817be9a9 <+57>:    mov    $0x200,%esi
   0xffffffff817be9ae <+62>:    mov    $0xffffffff817be993,%rdi
   0xffffffff817be9b5 <+69>:    jmpq   0xffffffff81063aa0 <__local_bh_enable_ip>
   0xffffffff817be9ba <+74>:    mov    %rbp,%rdi
   0xffffffff817be9bd <+77>:    callq  0xffffffff817be8c0 <__lock_sock>
   0xffffffff817be9c2 <+82>:    jmp    0xffffffff817be993 <lock_sock_nested+35>
End of assembler dump.

NATIVE:

(gdb) disassemble lock_sock_nested
Dump of assembler code for function lock_sock_nested:
   0xffffffff817be970 <+0>:     push   %rbp
   0xffffffff817be971 <+1>:     mov    %rdi,%rbp
   0xffffffff817be974 <+4>:     push   %rbx
   0xffffffff817be975 <+5>:     lea    0x88(%rbp),%rbx
   0xffffffff817be97c <+12>:    callq  0xffffffff819f7160 <_cond_resched>
   0xffffffff817be981 <+17>:    mov    %rbx,%rdi
   0xffffffff817be984 <+20>:    callq  0xffffffff819fbb00 <_raw_spin_lock_bh>
   0xffffffff817be989 <+25>:    mov    0x8c(%rbp),%eax
   0xffffffff817be98f <+31>:    test   %eax,%eax
   0xffffffff817be991 <+33>:    jne    0xffffffff817be9ba <lock_sock_nested+74>
   0xffffffff817be993 <+35>:    movl   $0x1,0x8c(%rbp)
   0xffffffff817be99d <+45>:    mov    %rbx,%rdi
   0xffffffff817be9a0 <+48>:    movb   $0x0,(%rdi)
   0xffffffff817be9a3 <+51>:    nopl   0x0(%rax)
   0xffffffff817be9a7 <+55>:    pop    %rbx
   0xffffffff817be9a8 <+56>:    pop    %rbp
   0xffffffff817be9a9 <+57>:    mov    $0x200,%esi
   0xffffffff817be9ae <+62>:    mov    $0xffffffff817be993,%rdi
   0xffffffff817be9b5 <+69>:    jmpq   0xffffffff81063ae0 <__local_bh_enable_ip>
   0xffffffff817be9ba <+74>:    mov    %rbp,%rdi
   0xffffffff817be9bd <+77>:    callq  0xffffffff817be8c0 <__lock_sock>
   0xffffffff817be9c2 <+82>:    jmp    0xffffffff817be993 <lock_sock_nested+35>
End of assembler dump.

Fixes: 63f70270ccd9 ("[PATCH] i386: PARAVIRT: add common patching machinery")
Fixes: 3010a0663fd9 ("x86/paravirt, objtool: Annotate indirect calls")
Reported-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: dts: imx6sx: fix irq for pcie bridge

commit 1bcfe0564044be578841744faea1c2f46adc8178 upstream.

Use the correct IRQ line for the MSI controller in the PCIe host
controller. Apparently a different IRQ line is used compared to other
i.MX6 variants. Without this change MSI IRQs aren't properly propagated
to the upstream interrupt controller.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Fixes: b1d17f68e5c5 ("ARM: dts: imx: add initial imx6sx device tree source")
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

IB/ocrdma: fix out of bounds access to local buffer

commit 062d0f22a30c39840ea49b72cfcfc1aa4cc538fa upstream.

In write to debugfs file 'resource_stats' the local buffer 'tmp_str' is
written at index 'count-1' where 'count' is the size of the write, so
potentially 0.

This patch filters odd values for the write size/position to avoid this
type of problem.

Signed-off-by: Michael Mera <dev@michaelmera.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

IB/mlx4: Mark user MR as writable if actual virtual memory is writable

commit d8f9cc328c8888369880e2527e9186d745f2bbf6 upstream.

To allow rereg_user_mr to modify the MR from read-only to writable without
using get_user_pages again, we needed to define the initial MR as writable.
However, this was originally done unconditionally, without taking into
account the writability of the underlying virtual memory.

As a result, any attempt to register a read-only MR over read-only
virtual memory failed.

To fix this, do not add the writable flag bit when the user virtual memory
is not writable (e.g. const memory).

However, when the underlying memory is NOT writable (and we therefore
do not define the initial MR as writable), the IB core adds a
"force writable" flag to its user-pages request. If this succeeds,
the reg_user_mr caller gets a writable copy of the original pages.

If the user-space caller then does a rereg_user_mr operation to enable
writability, this will succeed. This should not be allowed, since
the original virtual memory was not writable.

Cc: <stable@vger.kernel.org>
Fixes: 9376932d0c26 ("IB/mlx4_ib: Add support for user MR re-registration")
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

IB/core: Make testing MR flags for writability a static inline function

commit 08bb558ac11ab944e0539e78619d7b4c356278bd upstream.

Make the MR writability flags check, which is performed in umem.c,
a static inline function in file ib_verbs.h

This allows the function to be used by low-level infiniband drivers.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fix __legitimize_mnt()/mntput() race

commit 119e1ef80ecfe0d1deb6378d4ab41f5b71519de1 upstream.

__legitimize_mnt() has two problems - one is that in case of success
the check of mount_lock is not ordered wrt preceding increment of
refcount, making it possible to have successful __legitimize_mnt()
on one CPU just before the otherwise final mntpu() on another,
with __legitimize_mnt() not seeing mntput() taking the lock and
mntput() not seeing the increment done by __legitimize_mnt().
Solved by a pair of barriers.

Another is that failure of __legitimize_mnt() on the second
read_seqretry() leaves us with reference that'll need to be
dropped by caller; however, if that races with final mntput()
we can end up with caller dropping rcu_read_lock() and doing
mntput() to release that reference - with the first mntput()
having freed the damn thing just as rcu_read_lock() had been
dropped.  Solution: in "do mntput() yourself" failure case
grab mount_lock, check if MNT_DOOMED has been set by racing
final mntput() that has missed our increment and if it has -
undo the increment and treat that as "failure, caller doesn't
need to drop anything" case.

It's not easy to hit - the final mntput() has to come right
after the first read_seqretry() in __legitimize_mnt() *and*
manage to miss the increment done by __legitimize_mnt() before
the second read_seqretry() in there.  The things that are almost
impossible to hit on bare hardware are not impossible on SMP
KVM, though...

Reported-by: Oleg Nesterov <oleg@redhat.com>
Fixes: 48a066e72d97 ("RCU'd vsfmounts")
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fix mntput/mntput race

commit 9ea0a46ca2c318fcc449c1e6b62a7230a17888f1 upstream.

mntput_no_expire() does the calculation of total refcount under mount_lock;
unfortunately, the decrement (as well as all increments) are done outside
of it, leading to false positives in the "are we dropping the last reference"
test.  Consider the following situation:
* mnt is a lazy-umounted mount, kept alive by two opened files.  One
of those files gets closed.  Total refcount of mnt is 2.  On CPU 42
mntput(mnt) (called from __fput()) drops one reference, decrementing component
* After it has looked at component #0, the process on CPU 0 does
mntget(), incrementing component #0, gets preempted and gets to run again -
on CPU 69.  There it does mntput(), which drops the reference (component #69)
and proceeds to spin on mount_lock.
* On CPU 42 our first mntput() finishes counting.  It observes the
decrement of component #69, but not the increment of component #0.  As the
result, the total it gets is not 1 as it should've been - it's 0.  At which
point we decide that vfsmount needs to be killed and proceed to free it and
shut the filesystem down.  However, there's still another opened file
on that filesystem, with reference to (now freed) vfsmount, etc. and we are
screwed.

It's not a wide race, but it can be reproduced with artificial slowdown of
the mnt_get_count() loop, and it should be easier to hit on SMP KVM setups.

Fix consists of moving the refcount decrement under mount_lock; the tricky
part is that we want (and can) keep the fast case (i.e. mount that still
has non-NULL ->mnt_ns) entirely out of mount_lock.  All places that zero
mnt->mnt_ns are dropping some reference to mnt and they call synchronize_rcu()
before that mntput().  IOW, if mntput() observes (under rcu_read_lock())
a non-NULL ->mnt_ns, it is guaranteed that there is another reference yet to
be dropped.

Reported-by: Jann Horn <jannh@google.com>
Tested-by: Jann Horn <jannh@google.com>
Fixes: 48a066e72d97 ("RCU'd vsfmounts")
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

root dentries need RCU-delayed freeing

commit 90bad5e05bcdb0308cfa3d3a60f5c0b9c8e2efb3 upstream.

Since mountpoint crossing can happen without leaving lazy mode,
root dentries do need the same protection against having their
memory freed without RCU delay as everything else in the tree.

It's partially hidden by RCU delay between detaching from the
mount tree and dropping the vfsmount reference, but the starting
point of pathwalk can be on an already detached mount, in which
case umount-caused RCU delay has already passed by the time the
lazy pathwalk grabs rcu_read_lock().  If the starting point
happens to be at the root of that vfsmount *and* that vfsmount
covers the entire filesystem, we get trouble.

Fixes: 48a066e72d97 ("RCU'd vsfmounts")
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: sr: Avoid that opening a CD-ROM hangs with runtime power management enabled

commit 1214fd7b497400d200e3f4e64e2338b303a20949 upstream.

Surround scsi_execute() calls with scsi_autopm_get_device() and
scsi_autopm_put_device(). Note: removing sr_mutex protection from the
scsi_cd_get() and scsi_cd_put() calls is safe because the purpose of
sr_mutex is to serialize cdrom_*() calls.

This patch avoids that complaints similar to the following appear in the
kernel log if runtime power management is enabled:

INFO: task systemd-udevd:650 blocked for more than 120 seconds.
     Not tainted 4.18.0-rc7-dbg+ #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
systemd-udevd   D28176   650    513 0x00000104
Call Trace:
__schedule+0x444/0xfe0
schedule+0x4e/0xe0
schedule_preempt_disabled+0x18/0x30
__mutex_lock+0x41c/0xc70
mutex_lock_nested+0x1b/0x20
__blkdev_get+0x106/0x970
blkdev_get+0x22c/0x5a0
blkdev_open+0xe9/0x100
do_dentry_open.isra.19+0x33e/0x570
vfs_open+0x7c/0xd0
path_openat+0x6e3/0x1120
do_filp_open+0x11c/0x1c0
do_sys_open+0x208/0x2d0
__x64_sys_openat+0x59/0x70
do_syscall_64+0x77/0x230
entry_SYSCALL_64_after_hwframe+0x49/0xbe

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Maurizio Lombardi <mlombard@redhat.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: <stable@vger.kernel.org>
Tested-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ACPI / LPSS: Add missing prv_offset setting for byt/cht PWM devices

commit fdcb613d49321b5bf5d5a1bd0fba8e7c241dcc70 upstream.

The LPSS PWM device on on Bay Trail and Cherry Trail devices has a set
of private registers at offset 0x800, the current lpss_device_desc for
them already sets the LPSS_SAVE_CTX flag to have these saved/restored
over device-suspend, but the current lpss_device_desc was not setting
the prv_offset field, leading to the regular device registers getting
saved/restored instead.

This is causing the PWM controller to no longer work, resulting in a black
screen,  after a suspend/resume on systems where the firmware clears the
APB clock and reset bits at offset 0x804.

This commit fixes this by properly setting prv_offset to 0x800 for
the PWM devices.

Cc: stable@vger.kernel.org
Fixes: e1c748179754 ("ACPI / LPSS: Add Intel BayTrail ACPI mode PWM")
Fixes: 1bfbd8eb8a7f ("ACPI / LPSS: Add ACPI IDs for Intel Braswell")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Rafael J . Wysocki <rjw@rjwysocki.net>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

xen/netfront: don't cache skb_shinfo()

commit d472b3a6cf63cd31cae1ed61930f07e6cd6671b5 upstream.

skb_shinfo() can change when calling __pskb_pull_tail(): Don't cache
its return value.

Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parisc: Define mb() and add memory barriers to assembler unlock sequences

commit fedb8da96355f5f64353625bf96dc69423ad1826 upstream.

For years I thought all parisc machines executed loads and stores in
order. However, Jeff Law recently indicated on gcc-patches that this is
not correct. There are various degrees of out-of-order execution all the
way back to the PA7xxx processor series (hit-under-miss). The PA8xxx
series has full out-of-order execution for both integer operations, and
loads and stores.

This is described in the following article:
http://web.archive.org/web/20040214092531/http://www.cpus.hp.com/technical_references/advperf.shtml

For this reason, we need to define mb() and to insert a memory barrier
before the store unlocking spinlocks. This ensures that all memory
accesses are complete prior to unlocking. The ldcw instruction performs
the same function on entry.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parisc: Enable CONFIG_MLONGCALLS by default

commit 66509a276c8c1d19ee3f661a41b418d101c57d29 upstream.

Enable the -mlong-calls compiler option by default, because otherwise in most
cases linking the vmlinux binary fails due to truncations of R_PARISC_PCREL22F
relocations. This fixes building the 64-bit defconfig.

Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fork: unconditionally clear stack on fork

commit e01e80634ecdde1dd113ac43b3adad21b47f3957 upstream.

One of the classes of kernel stack content leaks[1] is exposing the
contents of prior heap or stack contents when a new process stack is
allocated.  Normally, those stacks are not zeroed, and the old contents
remain in place.  In the face of stack content exposure flaws, those
contents can leak to userspace.

Fixing this will make the kernel no longer vulnerable to these flaws, as
the stack will be wiped each time a stack is assigned to a new process.
There's not a meaningful change in runtime performance; it almost looks
like it provides a benefit.

Performing back-to-back kernel builds before:
Run times: 157.86 157.09 158.90 160.94 160.80
Mean: 159.12
Std Dev: 1.54

and after:
Run times: 159.31 157.34 156.71 158.15 160.81
Mean: 158.46
Std Dev: 1.46

Instead of making this a build or runtime config, Andy Lutomirski
recommended this just be enabled by default.

[1] A noisy search for many kinds of stack content leaks can be seen here:
https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=linux+kernel+stack+leak

I did some more with perf and cycle counts on running 100,000 execs of
/bin/true.

before:
Cycles: 218858861551 218853036130 214727610969 227656844122 224980542841
Mean:  221015379122.60
Std Dev: 4662486552.47

after:
Cycles: 213868945060 213119275204 211820169456 224426673259 225489986348
Mean:  217745009865.40
Std Dev: 5935559279.99

It continues to look like it's faster, though the deviation is rather
wide, but I'm not sure what I could do that would be less noisy.  I'm
open to ideas!

Link: http://lkml.kernel.org/r/20180221021659.GA37073@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
[ Srivatsa: Backported to 4.4.y ]
Signed-off-by: Srivatsa S. Bhat <srivatsa@csail.mit.edu>
Reviewed-by: Srinidhi Rao <srinidhir@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ipv4+ipv6: Make INET*_ESP select CRYPTO_ECHAINIV

commit 32b6170ca59ccf07d0e394561e54b2cd9726038c upstream.

The ESP algorithms using CBC mode require echainiv. Hence INET*_ESP have
to select CRYPTO_ECHAINIV in order to work properly. This solves the
issues caused by a misconfiguration as described in [1].
The original approach, patching crypto/Kconfig was turned down by
Herbert Xu [2].

[1] https://lists.strongswan.org/pipermail/users/2015-December/009074.html
[2] http://marc.info/?l=linux-crypto-vger&m=145224655809562&w=2

Signed-off-by: Thomas Egerer <hakke_007@gmx.de>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Yongqin Liu <yongqin.liu@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tpm: fix race condition in tpm_common_write()

commit 3ab2011ea368ec3433ad49e1b9e1c7b70d2e65df upstream.

There is a race condition in tpm_common_write function allowing
two threads on the same /dev/tpm<N>, or two different applications
on the same /dev/tpmrm<N> to overwrite each other commands/responses.
Fixed this by taking the priv->buffer_mutex early in the function.

Also converted the priv->data_pending from atomic to a regular size_t
type. There is no need for it to be atomic since it is only touched
under the protection of the priv->buffer_mutex.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ext4: fix check to prevent initializing reserved inodes

commit 5012284700775a4e6e3fbe7eac4c543c4874b559 upstream.

Commit 8844618d8aa7: "ext4: only look at the bg_flags field if it is
valid" will complain if block group zero does not have the
EXT4_BG_INODE_ZEROED flag set.  Unfortunately, this is not correct,
since a freshly created file system has this flag cleared.  It gets
almost immediately after the file system is mounted read-write --- but
the following somewhat unlikely sequence will end up triggering a
false positive report of a corrupted file system:

   mkfs.ext4 /dev/vdc
   mount -o ro /dev/vdc /vdc
   mount -o remount,rw /dev/vdc

Instead, when initializing the inode table for block group zero, test
to make sure that itable_unused count is not too large, since that is
the case that will result in some or all of the reserved inodes
getting cleared.

This fixes the failures reported by Eric Whiteney when running
generic/230 and generic/231 in the the nojournal test case.

Fixes: 8844618d8aa7 ("ext4: only look at the bg_flags field if it is valid")
Reported-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge tag 'v4.4.147' into linux-linaro-lsk-v4.4

This is the 4.4.147 stable release

Linux 4.4.147

jfs: Fix inconsistency between memory allocation and ea_buf->max_size

commit 92d34134193e5b129dc24f8d79cb9196626e8d7a upstream.

The code is assuming the buffer is max_size length, but we weren't
allocating enough space for it.

Signed-off-by: Shankara Pailoor <shankarapailoor@gmail.com>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

i2c: imx: Fix reinit_completion() use

commit 9f9e3e0d4dd3338b3f3dde080789f71901e1e4ff upstream.

Make sure to call reinit_completion() before dma is started to avoid race
condition where reinit_completion() is called after complete() and before
wait_for_completion_timeout().

Signed-off-by: Esben Haabendal <eha@deif.com>
Fixes: ce1a78840ff7 ("i2c: imx: add DMA support for freescale i2c driver")
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ring_buffer: tracing: Inherit the tracing setting to next ring buffer

commit 73c8d8945505acdcbae137c2e00a1232e0be709f upstream.

Maintain the tracing on/off setting of the ring_buffer when switching
to the trace buffer snapshot.

Taking a snapshot is done by swapping the backup ring buffer
(max_tr_buffer). But since the tracing on/off setting is defined
by the ring buffer, when swapping it, the tracing on/off setting
can also be changed. This causes a strange result like below:

  /sys/kernel/debug/tracing # cat tracing_on
  1
  /sys/kernel/debug/tracing # echo 0 > tracing_on
  /sys/kernel/debug/tracing # cat tracing_on
  0
  /sys/kernel/debug/tracing # echo 1 > snapshot
  /sys/kernel/debug/tracing # cat tracing_on
  1
  /sys/kernel/debug/tracing # echo 1 > snapshot
  /sys/kernel/debug/tracing # cat tracing_on
  0

We don't touch tracing_on, but snapshot changes tracing_on
setting each time. This is an anomaly, because user doesn't know
that each "ring_buffer" stores its own tracing-enable state and
the snapshot is done by swapping ring buffers.

Link: http://lkml.kernel.org/r/153149929558.11274.11730609978254724394.stgit@devbox
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Hiraku Toyooka <hiraku.toyooka@cybertrust.co.jp>
Cc: stable@vger.kernel.org
Fixes: debdd57f5145 ("tracing: Make a snapshot feature available from userspace")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[ Updated commit log and comment in the code ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ACPI / PCI: Bail early in acpi_pci_add_bus() if there is no ACPI handle

commit a0040c0145945d3bd203df8fa97f6dfa819f3f7d upstream.

Hyper-V instances support PCI pass-through which is implemented through PV
pci-hyperv driver. When a device is passed through, a new root PCI bus is
created in the guest. The bus sits on top of VMBus and has no associated
information in ACPI. acpi_pci_add_bus() in this case proceeds all the way
to acpi_evaluate_dsm(), which reports

  ACPI: \: failed to evaluate _DSM (0x1001)

While acpi_pci_slot_enumerate() and acpiphp_enumerate_slots() are protected
against ACPI_HANDLE() being NULL and do nothing, acpi_evaluate_dsm() is not
and gives us the error. It seems the correct fix is to not do anything in
acpi_pci_add_bus() in such cases.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sinan Kaya <okaya@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ext4: fix false negatives *and* false positives in ext4_check_descriptors()

commit 44de022c4382541cebdd6de4465d1f4f465ff1dd upstream.

Ext4_check_descriptors() was getting called before s_gdb_count was
initialized.  So for file systems w/o the meta_bg feature, allocation
bitmaps could overlap the block group descriptors and ext4 wouldn't
notice.

For file systems with the meta_bg feature enabled, there was a
fencepost error which would cause the ext4_check_descriptors() to
incorrectly believe that the block allocation bitmap overlaps with the
block group descriptor blocks, and it would reject the mount.

Fix both of these problems.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Gilbert <bgilbert@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

netlink: Don't shift on 64 for ngroups

commit 91874ecf32e41b5d86a4cb9d60e0bee50d828058 upstream.

It's legal to have 64 groups for netlink_sock.

As user-supplied nladdr->nl_groups is __u32, it's possible to subscribe
only to first 32 groups.

The check for correctness of .bind() userspace supplied parameter
is done by applying mask made from ngroups shift. Which broke Android
as they have 64 groups and the shift for mask resulted in an overflow.

Fixes: 61f4b23769f0 ("netlink: Don't shift with UB on nlk->ngroups")
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: netdev@vger.kernel.org
Cc: stable@vger.kernel.org
Reported-and-Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

netlink: Don't shift with UB on nlk->ngroups

[ Upstream commit 61f4b23769f0cc72ae62c9a81cf08f0397d40da8 ]

On i386 nlk->ngroups might be 32 or 0. Which leads to UB, resulting in
hang during boot.
Check for 0 ngroups and use (unsigned long long) as a type to shift.

Fixes: 7acf9d4237c4 ("netlink: Do not subscribe to non-existent groups").
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

netlink: Do not subscribe to non-existent groups

[ Upstream commit 7acf9d4237c46894e0fa0492dd96314a41742e84 ]

Make ABI more strict about subscribing to group > ngroups.
Code doesn't check for that and it looks bogus.
(one can subscribe to non-existing group)
Still, it's possible to bind() to all possible groups with (-1)

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: netdev@vger.kernel.org
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

nohz: Fix local_timer_softirq_pending()

commit 80d20d35af1edd632a5e7a3b9c0ab7ceff92769e upstream.

local_timer_softirq_pending() checks whether the timer softirq is
pending with: local_softirq_pending() & TIMER_SOFTIRQ.

This is wrong because TIMER_SOFTIRQ is the softirq number and not a
bitmask. So the test checks for the wrong bit.

Use BIT(TIMER_SOFTIRQ) instead.

Fixes: 5d62c183f9e9 ("nohz: Prevent a timer interrupt storm in tick_nohz_stop_sched_tick()")
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Cc: bigeasy@linutronix.de
Cc: peterz@infradead.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180731161358.29472-1-anna-maria@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

genirq: Make force irq threading setup more robust

commit d1f0301b3333eef5efbfa1fe0f0edbea01863d5d upstream.

The support of force threading interrupts which are set up with both a
primary and a threaded handler wreckaged the setup of regular requested
threaded interrupts (primary handler == NULL).

The reason is that it does not check whether the primary handler is set to
the default handler which wakes the handler thread. Instead it replaces the
thread handler with the primary handler as it would do with force threaded
interrupts which have been requested via request_irq(). So both the primary
and the thread handler become the same which then triggers the warnon that
the thread handler tries to wakeup a not configured secondary thread.

Fortunately this only happens when the driver omits the IRQF_ONESHOT flag
when requesting the threaded interrupt, which is normaly caught by the
sanity checks when force irq threading is disabled.

Fix it by skipping the force threading setup when a regular threaded
interrupt is requested. As a consequence the interrupt request which lacks
the IRQ_ONESHOT flag is rejected correctly instead of silently wreckaging
it.

Fixes: 2a1d3ab8986d ("genirq: Handle force threading of irqs with primary and thread handler")
Reported-by: Kurt Kanzenbach <kurt.kanzenbach@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Kurt Kanzenbach <kurt.kanzenbach@linutronix.de>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: qla2xxx: Return error when TMF returns

commit b4146c4929ef61d5afca011474d59d0918a0cd82 upstream.

Propagate the task management completion status properly to avoid
unnecessary waits for commands to complete.

Fixes: faef62d13463 ("[SCSI] qla2xxx: Fix Task Management command asynchronous handling")
Cc: <stable@vger.kernel.org>
Signed-off-by: Anil Gurumurthy <anil.gurumurthy@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: qla2xxx: Fix ISP recovery on unload

commit b08abbd9f5996309f021684f9ca74da30dcca36a upstream.

During unload process, the chip can encounter problem where a FW dump would
be captured. For this case, the full reset sequence will be skip to bring
the chip back to full operational state.

Fixes: e315cd28b9ef ("[SCSI] qla2xxx: Code changes for qla data structure refactoring")
Cc: <stable@vger.kernel.org>
Signed-off-by: Quinn Tran <quinn.tran@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge tag 'v4.4.146' into linux-linaro-lsk-v4.4

This is the 4.4.146 stable release

Linux 4.4.146

scsi: sg: fix minor memory leak in error path

commit c170e5a8d222537e98aa8d4fddb667ff7a2ee114 upstream.

Fix a minor memory leak when there is an error opening a /dev/sg device.

Fixes: cc833acbee9d ("sg: O_EXCL and other lock handling")
Cc: <stable@vger.kernel.org>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

crypto: padlock-aes - Fix Nano workaround data corruption

commit 46d8c4b28652d35dc6cfb5adf7f54e102fc04384 upstream.

This was detected by the self-test thanks to Ard's chunking patch.

I finally got around to testing this out on my ancient Via box.  It
turns out that the workaround got the assembly wrong and we end up
doing count + initial cycles of the loop instead of just count.

This obviously causes corruption, either by overwriting the source
that is yet to be processed, or writing over the end of the buffer.

On CPUs that don't require the workaround only ECB is affected.
On Nano CPUs both ECB and CBC are affected.

This patch fixes it by doing the subtraction prior to the assembly.

Fixes: a76c1c23d0c3 ("crypto: padlock-aes - work around Nano CPU...")
Cc: <stable@vger.kernel.org>
Reported-by: Jamie Heilman <jamie@audible.transient.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kvm: x86: vmx: fix vpid leak

commit 63aff65573d73eb8dda4732ad4ef222dd35e4862 upstream.

VPID for the nested vcpu is allocated at vmx_create_vcpu whenever nested
vmx is turned on with the module parameter.

However, it's only freed if the L1 guest has executed VMXON which is not
a given.

As a result, on a system with nested==on every creation+deletion of an
L1 vcpu without running an L2 guest results in leaking one vpid.  Since
the total number of vpids is limited to 64k, they can eventually get
exhausted, preventing L2 from starting.

Delay allocation of the L2 vpid until VMXON emulation, thus matching its
freeing.

Fixes: 5c614b3583e7b6dab0c86356fa36c2bcbb8322a0
Cc: stable@vger.kernel.org
Signed-off-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

virtio_balloon: fix another race between migration and ballooning

commit 89da619bc18d79bca5304724c11d4ba3b67ce2c6 upstream.

Kernel panic when with high memory pressure, calltrace looks like,

PID: 21439 TASK: ffff881be3afedd0 CPU: 16 COMMAND: "java"
 #0 [ffff881ec7ed7630] machine_kexec at ffffffff81059beb
 #1 [ffff881ec7ed7690] __crash_kexec at ffffffff81105942
 #2 [ffff881ec7ed7760] crash_kexec at ffffffff81105a30
 #3 [ffff881ec7ed7778] oops_end at ffffffff816902c8
 #4 [ffff881ec7ed77a0] no_context at ffffffff8167ff46
 #5 [ffff881ec7ed77f0] __bad_area_nosemaphore at ffffffff8167ffdc
 #6 [ffff881ec7ed7838] __node_set at ffffffff81680300
 #7 [ffff881ec7ed7860] __do_page_fault at ffffffff8169320f
 #8 [ffff881ec7ed78c0] do_page_fault at ffffffff816932b5
 #9 [ffff881ec7ed78f0] page_fault at ffffffff8168f4c8
    [exception RIP: _raw_spin_lock_irqsave+47]
    RIP: ffffffff8168edef RSP: ffff881ec7ed79a8 RFLAGS: 00010046
    RAX: 0000000000000246 RBX: ffffea0019740d00 RCX: ffff881ec7ed7fd8
    RDX: 0000000000020000 RSI: 0000000000000016 RDI: 0000000000000008
    RBP: ffff881ec7ed79a8 R8: 0000000000000246 R9: 000000000001a098
    R10: ffff88107ffda000 R11: 0000000000000000 R12: 0000000000000000
    R13: 0000000000000008 R14: ffff881ec7ed7a80 R15: ffff881be3afedd0
    ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018

It happens in the pagefault and results in double pagefault
during compacting pages when memory allocation fails.

Analysed the vmcore, the page leads to second pagefault is corrupted
with _mapcount=-256, but private=0.

It's caused by the race between migration and ballooning, and lock
missing in virtballoon_migratepage() of virtio_balloon driver.
This patch fix the bug.

Fixes: e22504296d4f64f ("virtio_balloon: introduce migration primitives to balloon pages")
Cc: stable@vger.kernel.org
Signed-off-by: Jiang Biao <jiang.biao2@zte.com.cn>
Signed-off-by: Huang Chong <huang.chong@zte.com.cn>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net: socket: fix potential spectre v1 gadget in socketcall

commit c8e8cd579bb4265651df8223730105341e61a2d1 upstream.

'call' is a user-controlled value, so sanitize the array index after the
bounds check to avoid speculating past the bounds of the 'nargs' array.

Found with the help of Smatch:

net/socket.c:2508 __do_sys_socketcall() warn: potential spectre issue
'nargs' [r] (local cap)

Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jeremy Cline <jcline@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

can: ems_usb: Fix memory leak on ems_usb_disconnect()

commit 72c05f32f4a5055c9c8fe889bb6903ec959c0aad upstream.

ems_usb_probe() allocates memory for dev->tx_msg_buffer, but there
is no its deallocation in ems_usb_disconnect().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Anton Vasilyev <vasilyev@ispras.ru>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

squashfs: more metadata hardenings

commit 71755ee5350b63fb1f283de8561cdb61b47f4d1d upstream.

The squashfs fragment reading code doesn't actually verify that the
fragment is inside the fragment table.  The end result _is_ verified to
be inside the image when actually reading the fragment data, but before
that is done, we may end up taking a page fault because the fragment
table itself might not even exist.

Another report from Anatoly and his endless squashfs image fuzzing.

Reported-by: Анатолий Тросиненко <anatoly.trosinenko@gmail.com>
Acked-by:: Phillip Lougher <phillip.lougher@gmail.com>,
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

squashfs: more metadata hardening

commit d512584780d3e6a7cacb2f482834849453d444a1 upstream.

Anatoly reports another squashfs fuzzing issue, where the decompression
parameters themselves are in a compressed block.

This causes squashfs_read_data() to be called in order to read the
decompression options before the decompression stream having been set
up, making squashfs go sideways.

Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Acked-by: Phillip Lougher <phillip.lougher@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

netlink: Fix spectre v1 gadget in netlink_create()

[ Upstream commit bc5b6c0b62b932626a135f516a41838c510c6eba ]

'protocol' is a user-controlled value, so sanitize it after the bounds
check to avoid using it for speculative out-of-bounds access to arrays
indexed by it.

This addresses the following accesses detected with the help of smatch:

* net/netlink/af_netlink.c:654 __netlink_create() warn: potential
  spectre issue 'nlk_cb_mutex_keys' [w]

* net/netlink/af_netlink.c:654 __netlink_create() warn: potential
  spectre issue 'nlk_cb_mutex_key_strings' [w]

* net/netlink/af_netlink.c:685 netlink_create() warn: potential spectre
  issue 'nl_table' [w] (local cap)

Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Jeremy Cline <jcline@redhat.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net: dsa: Do not suspend/resume closed slave_dev

[ Upstream commit a94c689e6c9e72e722f28339e12dff191ee5a265 ]

If a DSA slave network device was previously disabled, there is no need
to suspend or resume it.

Fixes: 2446254915a7 ("net: dsa: allow switch drivers to implement suspend/resume hooks")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

inet: frag: enforce memory limits earlier

[ Upstream commit 56e2c94f055d328f5f6b0a5c1721cca2f2d4e0a1 ]

We currently check current frags memory usage only when
a new frag queue is created. This allows attackers to first
consume the memory budget (default : 4 MB) creating thousands
of frag queues, then sending tiny skbs to exceed high_thresh
limit by 2 to 3 order of magnitude.

Note that before commit 648700f76b03 ("inet: frags: use rhashtables
for reassembly units"), work queue could be starved under DOS,
getting no cpu cycles.
After commit 648700f76b03, only the per frag queue timer can eventually
remove an incomplete frag queue and its skbs.

Fixes: b13d3cbfb8e8 ("inet: frag: move eviction of queues to work queue")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jann Horn <jannh@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Peter Oskolkov <posk@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tcp: add one more quick ack after after ECN events

[ Upstream commit 15ecbe94a45ef88491ca459b26efdd02f91edb6d ]

Larry Brakmo proposal ( https://patchwork.ozlabs.org/patch/935233/
tcp: force cwnd at least 2 in tcp_cwnd_reduction) made us rethink
about our recent patch removing ~16 quick acks after ECN events.

tcp_enter_quickack_mode(sk, 1) makes sure one immediate ack is sent,
but in the case the sender cwnd was lowered to 1, we do not want
to have a delayed ack for the next packet we will receive.

Fixes: 522040ea5fdd ("tcp: do not aggressively quick ack after ECN events")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Neal Cardwell <ncardwell@google.com>
Cc: Lawrence Brakmo <brakmo@fb.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tcp: refactor tcp_ecn_check_ce to remove sk type cast

[ Upstream commit f4c9f85f3b2cb7669830cd04d0be61192a4d2436 ]

Refactor tcp_ecn_check_ce and __tcp_ecn_check_ce to accept struct sock*
instead of tcp_sock* to clean up type casts. This is a pure refactor
patch.

Signed-off-by: Yousuk Seung <ysseung@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tcp: do not aggressively quick ack after ECN events

[ Upstream commit 522040ea5fdd1c33bbf75e1d7c7c0422b96a94ef ]

ECN signals currently forces TCP to enter quickack mode for
up to 16 (TCP_MAX_QUICKACKS) following incoming packets.

We believe this is not needed, and only sending one immediate ack
for the current packet should be enough.

This should reduce the extra load noticed in DCTCP environments,
after congestion events.

This is part 2 of our effort to reduce pure ACK packets.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tcp: add max_quickacks param to tcp_incr_quickack and tcp_enter_quickack_mode

[ Upstream commit 9a9c9b51e54618861420093ae6e9b50a961914c5 ]

We want to add finer control of the number of ACK packets sent after
ECN events.

This patch is not changing current behavior, it only enables following
change.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tcp: do not force quickack when receiving out-of-order packets

[ Upstream commit a3893637e1eb0ef5eb1bbc52b3a8d2dfa317a35d ]

As explained in commit 9f9843a751d0 ("tcp: properly handle stretch
acks in slow start"), TCP stacks have to consider how many packets
are acknowledged in one single ACK, because of GRO, but also
because of ACK compression or losses.

We plan to add SACK compression in the following patch, we
must therefore not call tcp_enter_quickack_mode()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

NET: stmmac: align DMA stuff to largest cache line length

[ Upstream commit 9939a46d90c6c76f4533d534dbadfa7b39dc6acc ]

As for today STMMAC_ALIGN macro (which is used to align DMA stuff)
relies on L1 line length (L1_CACHE_BYTES).
This isn't correct in case of system with several cache levels
which might have L1 cache line length smaller than L2 line. This
can lead to sharing one cache line between DMA buffer and other
data, so we can lose this data while invalidate DMA buffer before
DMA transaction.

Fix that by using SMP_CACHE_BYTES instead of L1_CACHE_BYTES for
aligning.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

xen-netfront: wait xenbus state change when load module manually

[ Upstream commit 822fb18a82abaf4ee7058793d95d340f5dab7bfc ]

When loading module manually, after call xenbus_switch_state to initializes
the state of the netfront device, the driver state did not change so fast
that may lead no dev created in latest kernel. This patch adds wait to make
sure xenbus knows the driver is not in closed/unknown state.

Current state:
[vm]# ethtool eth0
Settings for eth0:
Link detected: yes
[vm]# modprobe -r xen_netfront
[vm]# modprobe  xen_netfront
[vm]# ethtool eth0
Settings for eth0:
Cannot get device settings: No such device
Cannot get wake-on-lan settings: No such device
Cannot get message level: No such device
Cannot get link status: No such device
No data available

With the patch installed.
[vm]# ethtool eth0
Settings for eth0:
Link detected: yes
[vm]# modprobe -r xen_netfront
[vm]# modprobe xen_netfront
[vm]# ethtool eth0
Settings for eth0:
Link detected: yes

Signed-off-by: Xiao Liang <xiliang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>