NFSD: memory corruption due to writing beyond the stat array
commit6c1ab83daaff423f23209f981936473364bda02f
authorKonstantin Khorenko <khorenko@parallels.com>
Tue, 1 Feb 2011 14:16:29 +0000 (1 17:16 +0300)
committerAK <andi@firstfloor.org>
Thu, 31 Mar 2011 18:58:02 +0000 (31 11:58 -0700)
treefed48205ab440e8453c0aca043246b7e7589be40
parentcec5d24f1ce6c52f5d2ed93b845e0de40127c88c
NFSD: memory corruption due to writing beyond the stat array

commit 3aa6e0aa8ab3e64bbfba092c64d42fd1d006b124 upstream.

If nfsd fails to find an exported via NFS file in the readahead cache, it
should increment corresponding nfsdstats counter (ra_depth[10]), but due to a
bug it may instead write to ra_depth[11], corrupting the following field.

In a kernel with NFSDv4 compiled in the corruption takes the form of an
increment of a counter of the number of NFSv4 operation 0's received; since
there is no operation 0, this is harmless.

In a kernel with NFSDv4 disabled it corrupts whatever happens to be in the
memory beyond nfsdstats.

Signed-off-by: Konstantin Khorenko <khorenko@openvz.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
fs/nfsd/vfs.c