[PATCH 6.6 273/396] xfs: ensure logflagsp is initialized in xfs_bmap_del_extent_real

Greg Kroah-Hartman
2024-04-01T16:50:44Z

From: Jiachen Zhang <zhangjiachen.jaycee@bytedance.com>

commit e6af9c98cbf0164a619d95572136bfb54d482dd6 upstream.

In the case of returning -ENOSPC, ensure logflagsp is initialized by 0.
Otherwise the caller __xfs_bunmapi will set uninitialized illegal
tmp_logflags value into xfs log, which might cause unpredictable error
in the log recovery procedure.

Also, remove the flags variable and set the *logflagsp directly, so that
the code should be more robust in the long run.

Fixes: 1b24b633aafe ("xfs: move some more code into xfs_bmap_del_extent_real")
Signed-off-by: Jiachen Zhang <zhangjiachen.jaycee@bytedance.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandanbabu@kernel.org>
Signed-off-by: Catherine Hoang <catherine.hoang@oracle.com>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/xfs/libxfs/xfs_bmap.c | 73 +++++++++++++++++++----------------------------
1 file changed, 31 insertions(+), 42 deletions(-)

--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -5014,7 +5014,6 @@ xfs_bmap_del_extent_real(
xfs_fileoff_t del_endoff; /* first offset past del */
int do_fx; /* free extent at end of routine */
int error; /* error return value */
- int flags = 0;/* inode logging flags */
struct xfs_bmbt_irec got; /* current extent entry */
xfs_fileoff_t got_endoff; /* first offset past got */
int i; /* temp state */
@@ -5027,6 +5026,8 @@ xfs_bmap_del_extent_real(
uint32_t state = xfs_bmap_fork_to_state(whichfork);
struct xfs_bmbt_irec old;

+ *logflagsp = 0;
+
mp = ip->i_mount;
XFS_STATS_INC(mp, xs_del_exlist);

@@ -5039,7 +5040,6 @@ xfs_bmap_del_extent_real(
ASSERT(got_endoff >= del_endoff);
ASSERT(!isnullstartblock(got.br_startblock));
qfield = 0;
- error = 0;

/*
* If it's the case where the directory code is running with no block
@@ -5055,13 +5055,13 @@ xfs_bmap_del_extent_real(
del->br_startoff > got.br_startoff && del_endoff < got_endoff)
return -ENOSPC;

- flags = XFS_ILOG_CORE;
+ *logflagsp = XFS_ILOG_CORE;
if (whichfork == XFS_DATA_FORK && XFS_IS_REALTIME_INODE(ip)) {
if (!(bflags & XFS_BMAPI_REMAP)) {
error = xfs_rtfree_blocks(tp, del->br_startblock,
del->br_blockcount);
if (error)
- goto done;
+ return error;
}

do_fx = 0;
@@ -5076,11 +5076,9 @@ xfs_bmap_del_extent_real(
if (cur) {
error = xfs_bmbt_lookup_eq(cur, &got, &i);
if (error)
- goto done;
- if (XFS_IS_CORRUPT(mp, i != 1)) {
- error = -EFSCORRUPTED;
- goto done;
- }
+ return error;
+ if (XFS_IS_CORRUPT(mp, i != 1))
+ return -EFSCORRUPTED;
}

if (got.br_startoff == del->br_startoff)
@@ -5097,17 +5095,15 @@ xfs_bmap_del_extent_real(
xfs_iext_prev(ifp, icur);
ifp->if_nextents--;

- flags |= XFS_ILOG_CORE;
+ *logflagsp |= XFS_ILOG_CORE;
if (!cur) {
- flags |= xfs_ilog_fext(whichfork);
+ *logflagsp |= xfs_ilog_fext(whichfork);
break;
}
if ((error = xfs_btree_delete(cur, &i)))
- goto done;
- if (XFS_IS_CORRUPT(mp, i != 1)) {
- error = -EFSCORRUPTED;
- goto done;
- }
+ return error;
+ if (XFS_IS_CORRUPT(mp, i != 1))
+ return -EFSCORRUPTED;
break;
case BMAP_LEFT_FILLING:
/*
@@ -5118,12 +5114,12 @@ xfs_bmap_del_extent_real(
got.br_blockcount -= del->br_blockcount;
xfs_iext_update_extent(ip, state, icur, &got);
if (!cur) {
- flags |= xfs_ilog_fext(whichfork);
+ *logflagsp |= xfs_ilog_fext(whichfork);
break;
}
error = xfs_bmbt_update(cur, &got);
if (error)
- goto done;
+ return error;
break;
case BMAP_RIGHT_FILLING:
/*
@@ -5132,12 +5128,12 @@ xfs_bmap_del_extent_real(
got.br_blockcount -= del->br_blockcount;
xfs_iext_update_extent(ip, state, icur, &got);
if (!cur) {
- flags |= xfs_ilog_fext(whichfork);
+ *logflagsp |= xfs_ilog_fext(whichfork);
break;
}
error = xfs_bmbt_update(cur, &got);
if (error)
- goto done;
+ return error;
break;
case 0:
/*
@@ -5154,18 +5150,18 @@ xfs_bmap_del_extent_real(
new.br_state = got.br_state;
new.br_startblock = del_endblock;

- flags |= XFS_ILOG_CORE;
+ *logflagsp |= XFS_ILOG_CORE;
if (cur) {
error = xfs_bmbt_update(cur, &got);
if (error)
- goto done;
+ return error;
error = xfs_btree_increment(cur, 0, &i);
if (error)
- goto done;
+ return error;
cur->bc_rec.b = new;
error = xfs_btree_insert(cur, &i);
if (error && error != -ENOSPC)
- goto done;
+ return error;
/*
* If get no-space back from btree insert, it tried a
* split, and we have a zero block reservation. Fix up
@@ -5178,33 +5174,28 @@ xfs_bmap_del_extent_real(
*/
error = xfs_bmbt_lookup_eq(cur, &got, &i);
if (error)
- goto done;
- if (XFS_IS_CORRUPT(mp, i != 1)) {
- error = -EFSCORRUPTED;
- goto done;
- }
+ return error;
+ if (XFS_IS_CORRUPT(mp, i != 1))
+ return -EFSCORRUPTED;
/*
* Update the btree record back
* to the original value.
*/
error = xfs_bmbt_update(cur, &old);
if (error)
- goto done;
+ return error;
/*
* Reset the extent record back
* to the original value.
*/
xfs_iext_update_extent(ip, state, icur, &old);
- flags = 0;
- error = -ENOSPC;
- goto done;
- }
- if (XFS_IS_CORRUPT(mp, i != 1)) {
- error = -EFSCORRUPTED;
- goto done;
+ *logflagsp = 0;
+ return -ENOSPC;
}
+ if (XFS_IS_CORRUPT(mp, i != 1))
+ return -EFSCORRUPTED;
} else
- flags |= xfs_ilog_fext(whichfork);
+ *logflagsp |= xfs_ilog_fext(whichfork);

ifp->if_nextents++;
xfs_iext_next(ifp, icur);
@@ -5228,7 +5219,7 @@ xfs_bmap_del_extent_real(
((bflags & XFS_BMAPI_NODISCARD) ||
del->br_state == XFS_EXT_UNWRITTEN));
if (error)
- goto done;
+ return error;
}
}

@@ -5243,9 +5234,7 @@ xfs_bmap_del_extent_real(
if (qfield && !(bflags & XFS_BMAPI_REMAP))
xfs_trans_mod_dquot_byino(tp, ip, qfield, (long)-nblks);

-done:
- *logflagsp = flags;
- return error;
+ return 0;
}

/*