diff options
| author | Sage Weil <sage@inktank.com> | 2012-08-21 21:11:51 +0200 |
|---|---|---|
| committer | Sage Weil <sage@inktank.com> | 2012-08-22 00:55:28 +0200 |
| commit | 45f2e081f573526977abfa781a12728f83e9641f (patch) | |
| tree | 0335f7ad27ed8506504201a5e558126b2ede058f | |
| parent | libceph: avoid truncation due to racing banners (diff) | |
| download | linux-45f2e081f573526977abfa781a12728f83e9641f.tar.xz linux-45f2e081f573526977abfa781a12728f83e9641f.zip | |
ceph: avoid divide by zero in __validate_layout()
If "l->stripe_unit" is zero the the mod on the next line will cause a
divide by zero bug. This comes from the copy_from_user() in
ceph_ioctl_set_layout_policy(). Passing 0 is valid, though (it means
"do not change") so avoid the % check in that case.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Alex Elder <elder@inktank.com>
| -rw-r--r-- | fs/ceph/ioctl.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/ceph/ioctl.c b/fs/ceph/ioctl.c index 8e3fb69fbe62..1396ceb46797 100644 --- a/fs/ceph/ioctl.c +++ b/fs/ceph/ioctl.c @@ -42,7 +42,8 @@ static long __validate_layout(struct ceph_mds_client *mdsc, /* validate striping parameters */ if ((l->object_size & ~PAGE_MASK) || (l->stripe_unit & ~PAGE_MASK) || - ((unsigned)l->object_size % (unsigned)l->stripe_unit)) + (l->stripe_unit != 0 && + ((unsigned)l->object_size % (unsigned)l->stripe_unit))) return -EINVAL; /* make sure it's a valid data pool */ |