File xfsprogs-xfs_repair-rebuild-directory-when-non-root-leafn-blo.patch of Package xfsprogs.21555
From 3d2195e4ae45c142be8ec4600d44f23e31cf0cf2 Mon Sep 17 00:00:00 2001
From: "Darrick J. Wong" <darrick.wong@oracle.com>
Date: Wed, 12 Dec 2018 11:42:40 -0600
Subject: [PATCH] xfs_repair: rebuild directory when non-root leafn blocks
claim block 0
Git-commit: 3d2195e4ae45c142be8ec4600d44f23e31cf0cf2
Patch-mainline: v4.20.0-rc1
References: bsc#1181309
As explained in
71a6af8 Revert "xfs_repair: treat zero da btree pointers as corruption"
a single root LEAFN block can exist in a directory until it grows
further.
This is why, normally, we skip directories with a root marked
XFS_DIR2_LEAFN_MAGIC, as detected by the left-most leaf block being
found at file block 0.
However, if we traversed any level of a btree to get here (as
indicated by da_cursor.active > 0), then a leaf block claiming block
0 indicates corruption, and we should handle it as such, and rebuild
the directory.
This was found by repair repeatedly rebuilding a directory containing a
single leafn block (xfs/495).
Fixes: 67a79e2cc932 ("xfs_repair: treat zero da btree pointers as corruption")
Reported-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
[sandeen: clarify commit log, refer to revert commit]
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Acked-by: Anthony Iliopoulos <ailiop@suse.com>
---
repair/dir2.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/repair/dir2.c b/repair/dir2.c
index ba5763ed3d26..e67ec590c091 100644
--- a/repair/dir2.c
+++ b/repair/dir2.c
@@ -1243,10 +1243,21 @@ process_node_dir2(
/*
* Skip directories with a root marked XFS_DIR2_LEAFN_MAGIC
+ *
+ * Be careful here: If any level of the da cursor was filled out then
+ * the directory has a da btree containing an invalid before pointer to
+ * dblock 0, and we should move on to rebuilding the directory. If no
+ * levels in the da cursor got filled out, then we just have a single
+ * leafn block and we're done.
*/
if (bno == 0) {
- release_da_cursor(mp, &da_cursor, 0);
- return 0;
+ if (da_cursor.active > 0) {
+ err_release_da_cursor(mp, &da_cursor, 0);
+ return 1;
+ } else {
+ release_da_cursor(mp, &da_cursor, 0);
+ return 0;
+ }
} else {
/*
* Now pass cursor and bno into leaf-block processing routine.
--
2.30.0
