author | Pablo Neira <pablo@netfilter.org> | |
Tue, 1 Apr 2014 17:38:44 +0000 (19:38 +0200) | ||
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | |
Mon, 14 Apr 2014 13:42:18 +0000 (06:42 -0700) | ||
commit | dbd3f730cf94e5ff51c196f6765a87e9e113ee64 | |
tree | f4cc3976570623ae3ed8b4336b0db87c70f13cf4 | tree | snapshot (tar.xz tar.gz zip) |
parent | 2e6f312e108b9f5609d601c4988c479e5cc9330d | commit | diff |
netlink: don't compare the nul-termination in nla_strcmp
[ Upstream commit 8b7b932434f5eee495b91a2804f5b64ebb2bc835 ]
nla_strcmp compares the string length plus one, so it's implicitly
including the nul-termination in the comparison.
int nla_strcmp(const struct nlattr *nla, const char *str)
{
int len = strlen(str) + 1;
...
d = memcmp(nla_data(nla), str, len);
However, if NLA_STRING is used, userspace can send us a string without
the nul-termination. This is a problem since the string
comparison will not match as the last byte may be not the
nul-termination.
Fix this by skipping the comparison of the nul-termination if the
attribute data is nul-terminated. Suggested by Thomas Graf.
Cc: Florian Westphal <fw@strlen.de>
Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8b7b932434f5eee495b91a2804f5b64ebb2bc835 ]
nla_strcmp compares the string length plus one, so it's implicitly
including the nul-termination in the comparison.
int nla_strcmp(const struct nlattr *nla, const char *str)
{
int len = strlen(str) + 1;
...
d = memcmp(nla_data(nla), str, len);
However, if NLA_STRING is used, userspace can send us a string without
the nul-termination. This is a problem since the string
comparison will not match as the last byte may be not the
nul-termination.
Fix this by skipping the comparison of the nul-termination if the
attribute data is nul-terminated. Suggested by Thomas Graf.
Cc: Florian Westphal <fw@strlen.de>
Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
lib/nlattr.c | diff | blob | history |