Fix for buffer overflow in ldm_frag_add not sufficient

As Ben Hutchings discovered [1], the patch for CVE-2011-1017 (buffer
overflow in ldm_frag_add) is not sufficient.  The original patch in
commit c340b1d640 ("fs/partitions/ldm.c: fix oops caused by corrupted
partition table") does not consider that, for subsequent fragments,
previously allocated memory is used.

[1] http://lkml.org/lkml/2011/5/6/407

Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Timo Warns <warns@pre-sense.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Timo Warns 2011-05-19 09:24:17 +02:00 committed by Linus Torvalds
parent e6c9366b2a
commit cae13fe4cc
1 changed files with 5 additions and 0 deletions

View File

@ -1335,6 +1335,11 @@ static bool ldm_frag_add (const u8 *data, int size, struct list_head *frags)
list_add_tail (&f->list, frags);
found:
if (rec >= f->num) {
ldm_error("REC value (%d) exceeds NUM value (%d)", rec, f->num);
return false;
}
if (f->map & (1 << rec)) {
ldm_error ("Duplicate VBLK, part %d.", rec);
f->map &= 0x7F; /* Mark the group as broken */