ceph: fix three bugs, two in ceph_vxattrcb_file_layout()
In ceph_vxattrcb_file_layout(), there is a check to determine
whether a preferred PG should be formatted into the output buffer.
That check assumes that a preferred PG number of 0 indicates "no
preference," but that is wrong. No preference is indicated by a
negative (specifically, -1) PG number.
In addition, if that condition yields true, the preferred value
is formatted into a sized buffer, but the size consumed by the
earlier snprintf() call is not accounted for, opening up the
possibilty of a buffer overrun.
Finally, in ceph_vxattrcb_dir_rctime() where the nanoseconds part of
the time displayed did not include leading 0's, which led to
erroneous (sub-second portion of) time values being shown.
This fixes these three issues:
http://tracker.newdream.net/issues/2155
http://tracker.newdream.net/issues/2156
http://tracker.newdream.net/issues/2157
Signed-off-by: Alex Elder <elder@dreamhost.com>
Reviewed-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 8294f46..35b8633 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -79,7 +79,7 @@
static size_t ceph_vxattrcb_dir_rctime(struct ceph_inode_info *ci, char *val,
size_t size)
{
- return snprintf(val, size, "%ld.%ld", (long)ci->i_rctime.tv_sec,
+ return snprintf(val, size, "%ld.09%ld", (long)ci->i_rctime.tv_sec,
(long)ci->i_rctime.tv_nsec);
}
@@ -118,10 +118,15 @@
(unsigned long long)ceph_file_layout_su(ci->i_layout),
(unsigned long long)ceph_file_layout_stripe_count(ci->i_layout),
(unsigned long long)ceph_file_layout_object_size(ci->i_layout));
- if (ceph_file_layout_pg_preferred(ci->i_layout))
- ret += snprintf(val + ret, size, "preferred_osd=%lld\n",
+
+ if (ceph_file_layout_pg_preferred(ci->i_layout) >= 0) {
+ val += ret;
+ size -= ret;
+ ret += snprintf(val, size, "preferred_osd=%lld\n",
(unsigned long long)ceph_file_layout_pg_preferred(
ci->i_layout));
+ }
+
return ret;
}