xfs: strengthen AGI unlinked inode bucket pointer checks

Strengthen our checking of the AGI unlinked pointers when we start to
use them for updating the metadata.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
This commit is contained in:
Darrick J. Wong 2019-02-07 10:37:14 -08:00
parent 9a4a511864
commit 86bfd3750f
1 changed files with 14 additions and 11 deletions

View File

@ -1963,6 +1963,7 @@ xfs_iunlink(
struct xfs_dinode *dip;
struct xfs_buf *agibp;
struct xfs_buf *ibp;
xfs_agino_t next_agino;
xfs_agnumber_t agno = XFS_INO_TO_AGNO(mp, ip->i_ino);
xfs_agino_t agino = XFS_INO_TO_AGINO(mp, ip->i_ino);
short bucket_index = agino % XFS_AGI_UNLINKED_BUCKETS;
@ -1978,13 +1979,16 @@ xfs_iunlink(
agi = XFS_BUF_TO_AGI(agibp);
/*
* Get the index into the agi hash table for the
* list this inode will go on.
* Get the index into the agi hash table for the list this inode will
* go on. Make sure the pointer isn't garbage and that this inode
* isn't already on the list.
*/
ASSERT(agi->agi_unlinked[bucket_index]);
ASSERT(be32_to_cpu(agi->agi_unlinked[bucket_index]) != agino);
next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
if (next_agino == agino ||
!xfs_verify_agino_or_null(mp, agno, next_agino))
return -EFSCORRUPTED;
if (agi->agi_unlinked[bucket_index] != cpu_to_be32(NULLAGINO)) {
if (next_agino != NULLAGINO) {
/*
* There is already another inode in the bucket we need
* to add ourselves to. Add us at the front of the list.
@ -2045,17 +2049,17 @@ xfs_iunlink_remove(
agi = XFS_BUF_TO_AGI(agibp);
/*
* Get the index into the agi hash table for the
* list this inode will go on.
* Get the index into the agi hash table for the list this inode will
* go on. Make sure the head pointer isn't garbage.
*/
if (!xfs_verify_agino(mp, agno,
be32_to_cpu(agi->agi_unlinked[bucket_index]))) {
next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
if (!xfs_verify_agino(mp, agno, next_agino)) {
XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
agi, sizeof(*agi));
return -EFSCORRUPTED;
}
if (be32_to_cpu(agi->agi_unlinked[bucket_index]) == agino) {
if (next_agino == agino) {
/*
* We're at the head of the list. Get the inode's on-disk
* buffer to see if there is anyone after us on the list.
@ -2097,7 +2101,6 @@ xfs_iunlink_remove(
/*
* We need to search the list for the inode being freed.
*/
next_agino = be32_to_cpu(agi->agi_unlinked[bucket_index]);
last_ibp = NULL;
while (next_agino != agino) {
struct xfs_imap imap;