If we need to realloc the bplist[] array holding buffers for a given
directory, we don't initialize the new slots. This causes a problem
if the directory has holes, because those slots never get filled in.
At the end of the function we call libxfs_putbuf for every non-null
slot, and any uninitialized slots are segfault landmines.
Make sure we initialize all new slots to NULL for this reason.
Reported-by: Oleg Davydov <burunduk3@xxxxxxxxx>
Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
---
diff --git a/repair/phase6.c b/repair/phase6.c
index b87c751..9d24a4f 100644
--- a/repair/phase6.c
+++ b/repair/phase6.c
@@ -2348,6 +2348,8 @@ longform_dir2_entry_check(xfs_mount_t *mp,
db = xfs_dir2_da_to_db(mp->m_dir_geo, da_bno);
if (db >= num_bps) {
+ int last_size = num_bps;
+
/* more data blocks than expected */
num_bps = db + 1;
bplist = realloc(bplist, num_bps * sizeof(struct xfs_buf*));
@@ -2355,6 +2357,9 @@ longform_dir2_entry_check(xfs_mount_t *mp,
do_error(_("realloc failed in %s (%zu bytes)\n"),
__func__,
num_bps * sizeof(struct xfs_buf*));
+ /* Initialize the new elements */
+ for (i = last_size; i < num_bps; i++)
+ bplist[i] = NULL;
}
if (isblock)
