OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

libceph: fix overflow check in crush_decode() 

The existing overflow check (n > ULONG_MAX / b) didn't work, because
n = ULONG_MAX / b would both bypass the check and still overflow the
allocation size a + n * b.

The correct check should be (n > (ULONG_MAX - a) / b).

Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>
This commit is contained in:
Xi Wang 2012-02-16 11:55:48 -05:00 committed by Alex Elder
parent 810339ec2f
commit 6448669777
1 changed files with 2 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
net/ceph/osdmap.c
View File

@ -283,7 +283,8 @@ static struct crush_map *crush_decode(void *pbyval, void *end)
ceph_decode_32_safe(p, end, yes, bad);
#if BITS_PER_LONG == 32
err = -EINVAL;
if (yes > ULONG_MAX / sizeof(struct crush_rule_step))
if (yes > (ULONG_MAX - sizeof(*r))
/ sizeof(struct crush_rule_step))
goto bad;
#endif
r = c->rules[i] = kmalloc(sizeof(*r) +