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@xxxxxxxxxx> Signed-off-by: Sage Weil <sage@xxxxxxxxxxx> Reviewed-by: Alex Elder <elder@xxxxxxxxxxx> --- 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 8e3fb69..1396ceb 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 */ -- 1.7.9 -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html