[Cluster-devel] [gfs2-utils PATCH 30/47] fsck.gfs2: Do not invalidate metablocks of dinodes with invalid mode

[Bob Peterson]

Before this patch, when fsck.gfs2 encountered a dinode with an invalid
mode, it would take steps to invalidate its metadata. That's wrong
because if the mode is invalid, you don't know how to treat it.
It's especially wrong if its metadata references the same blocks
that other valid dinodes reference, because then we could end up
deleting blocks belonging to valid files and directories.

rhbz#902920
---
 gfs2/fsck/pass1.c | 25 ++++++++-----------------
 1 file changed, 8 insertions(+), 17 deletions(-)

diff --git a/gfs2/fsck/pass1.c b/gfs2/fsck/pass1.c
index 964e60b..0f3adfe 100644
--- a/gfs2/fsck/pass1.c
+++ b/gfs2/fsck/pass1.c
@@ -1005,23 +1005,14 @@ static int handle_ip(struct gfs2_sbd *sdp, struct gfs2_inode *ip)
 
 	error = set_ip_blockmap(ip, 1);
 	if (error == -EINVAL) {
-		/* We found a dinode that has an invalid mode, so we can't
-		   tell if it's a data file, directory or a socket.
-		   Regardless, we have to invalidate its metadata in case there
-		   are duplicate blocks referenced.  If we don't call
-		   check_metatree, the blocks it references will be deleted
-		   wholesale by pass2, and if any of those blocks are
-		   duplicates--referenced by another dinode for some reason--
-		   we will mark it free, even though it's in use.  In other
-		   words, we would introduce file system corruption. So we
-		   need to keep track of the fact that it's invalid and
-		   skip parts that we can't be sure of based on dinode type. */
-		log_debug("Invalid mode dinode found at block %lld (0x%llx): "
-			  "Invalidating all its metadata.\n",
-			  (unsigned long long)ip->i_di.di_num.no_addr,
-			  (unsigned long long)ip->i_di.di_num.no_addr);
-		check_metatree(ip, &invalidate_fxns);
-		check_inode_eattr(ip, &invalidate_fxns);
+		/* We found a dinode that has an invalid mode. At this point
+		   set_ip_blockmap returned an error, which means it never
+		   got inserted into the inode tree. Since we haven't even
+		   processed its metadata with pass1_fxns, none of its
+		   metadata will be flagged as metadata or data blocks yet.
+		   Therefore, we don't need to invalidate anything. */
+		fsck_blockmap_set(ip, ip->i_di.di_num.no_addr,
+				  _("invalid mode"), gfs2_block_free);
 		return 0;
 	} else if (error)
 		goto bad_dinode;
-- 
1.7.11.7