| Message ID | 480fc460-e8cd-cb34-924c-59c874ab393e@sandeen.net (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | xfs_repair: two fixes | expand |
On Mon, Oct 22, 2018 at 11:04:31PM -0500, Eric Sandeen wrote: > 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@gmail.com> > Signed-off-by: Eric Sandeen <sandeen@redhat.com> Yay realloc :P Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> --D > --- > > 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) >
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)
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@gmail.com> Signed-off-by: Eric Sandeen <sandeen@redhat.com> ---