gfs2: fix gfs2_find_jhead that returns uninitialized jhead with seq 0

When the first log header in a journal happens to have a sequence
number of 0, a bug in gfs2_find_jhead() causes it to prematurely exit,
and return an uninitialized jhead with seq 0. This can cause failures
in the caller. For instance, a mount fails in one test case.

The correct behavior is for it to continue searching through the journal
to find the correct journal head with the highest sequence number.

Fixes: f4686c26ec ("gfs2: read journal in large chunks")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This commit is contained in:
Abhi Das 2020-02-04 14:14:56 -06:00 committed by Andreas Gruenbacher
parent a62aa6f7f5
commit 7582026f6f

View File

@ -422,7 +422,7 @@ static bool gfs2_jhead_pg_srch(struct gfs2_jdesc *jd,
for (offset = 0; offset < PAGE_SIZE; offset += sdp->sd_sb.sb_bsize) {
if (!__get_log_header(sdp, kaddr + offset, 0, &lh)) {
if (lh.lh_sequence > head->lh_sequence)
if (lh.lh_sequence >= head->lh_sequence)
*head = lh;
else {
ret = true;