udf: Improve table length check to avoid possible overflow
authorJan Kara <jack@suse.cz>
Tue, 10 Jul 2012 15:58:04 +0000 (17:58 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 9 Aug 2012 15:31:36 +0000 (08:31 -0700)
commit664634f8a03e721a7fffb5f1e21cbdd806598cda
tree7ac4078aee20f705905be154ef083e7796ae4b8e
parent06e619c5073d1830f58039cd97e95ae184cf7bbb
udf: Improve table length check to avoid possible overflow

commit 57b9655d01ef057a523e810d29c37ac09b80eead upstream.

When a partition table length is corrupted to be close to 1 << 32, the
check for its length may overflow on 32-bit systems and we will think
the length is valid. Later on the kernel can crash trying to read beyond
end of buffer. Fix the check to avoid possible overflow.

Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/udf/super.c