| author | Steve Dickson <steved@redhat.com> | |
| Thu, 18 Sep 2014 13:13:17 +0000 (09:13 -0400) | ||
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
| Sun, 5 Oct 2014 21:54:10 +0000 (14:54 -0700) | ||
| commit | 648d333d7d845d4364d0fab9d31ebb48e4641bfb | |
| tree | 7a9975bf2705d7bc8d98c3cdde07ecfb4e4cee4d | tree | snapshot (tar.xz tar.gz zip) |
| parent | 47415d5452b8945bfbe7e2adb3fa15658b3c3d21 | commit | diff |
NFSv4: nfs4_state_manager() vs. nfs_server_remove_lists()
commit 080af20cc945d110f9912d01cf6b66f94a375b8d upstream.
There is a race between nfs4_state_manager() and
nfs_server_remove_lists() that happens during a nfsv3 mount.
The v3 mount notices there is already a supper block so
nfs_server_remove_lists() called which uses the nfs_client_lock
spin lock to synchronize access to the client list.
At the same time nfs4_state_manager() is running through
the client list looking for work to do, using the same
lock. When nfs4_state_manager() wins the race to the
list, a v3 client pointer is found and not ignored
properly which causes the panic.
Moving some protocol checks before the state checking
avoids the panic.
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 080af20cc945d110f9912d01cf6b66f94a375b8d upstream.
There is a race between nfs4_state_manager() and
nfs_server_remove_lists() that happens during a nfsv3 mount.
The v3 mount notices there is already a supper block so
nfs_server_remove_lists() called which uses the nfs_client_lock
spin lock to synchronize access to the client list.
At the same time nfs4_state_manager() is running through
the client list looking for work to do, using the same
lock. When nfs4_state_manager() wins the race to the
list, a v3 client pointer is found and not ignored
properly which causes the panic.
Moving some protocol checks before the state checking
avoids the panic.
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| fs/nfs/nfs4client.c | diff | blob | history |