[PATCH AUTOSEL 5.4 61/73] btrfs: remove BUG_ON() in find_parent_nodes()

[PATCH AUTOSEL 5.4 61/73] btrfs: remove BUG_ON() in find_parent_nodes()

[Sasha Levin]

From: Josef Bacik <josef@toxicpanda.com>

[ Upstream commit fcba0120edf88328524a4878d1d6f4ad39f2ec81 ]

We search for an extent entry with .offset = -1, which shouldn't be a
thing, but corruption happens.  Add an ASSERT() for the developers,
return -EUCLEAN for mortals.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/btrfs/backref.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 7f644a58db511..9044e7282d0b2 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -1208,7 +1208,12 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans,
 	ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 0);
 	if (ret < 0)
 		goto out;
-	BUG_ON(ret == 0);
+	if (ret == 0) {
+		/* This shouldn't happen, indicates a bug or fs corruption. */
+		ASSERT(ret != 0);
+		ret = -EUCLEAN;
+		goto out;
+	}
 
 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 	if (trans && likely(trans->type != __TRANS_DUMMY) &&
-- 
2.34.1

[PATCH AUTOSEL 5.4 62/73] btrfs: remove BUG_ON(!eie) in find_parent_nodes

[Sasha Levin]

From: Josef Bacik <josef@toxicpanda.com>

[ Upstream commit 9f05c09d6baef789726346397438cca4ec43c3ee ]

If we're looking for leafs that point to a data extent we want to record
the extent items that point at our bytenr.  At this point we have the
reference and we know for a fact that this leaf should have a reference
to our bytenr.  However if there's some sort of corruption we may not
find any references to our leaf, and thus could end up with eie == NULL.
Replace this BUG_ON() with an ASSERT() and then return -EUCLEAN for the
mortals.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/btrfs/backref.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 9044e7282d0b2..c701a19fac533 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -1361,10 +1361,18 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans,
 				goto out;
 			if (!ret && extent_item_pos) {
 				/*
-				 * we've recorded that parent, so we must extend
-				 * its inode list here
+				 * We've recorded that parent, so we must extend
+				 * its inode list here.
+				 *
+				 * However if there was corruption we may not
+				 * have found an eie, return an error in this
+				 * case.
 				 */
-				BUG_ON(!eie);
+				ASSERT(eie);
+				if (!eie) {
+					ret = -EUCLEAN;
+					goto out;
+				}
 				while (eie->next)
 					eie = eie->next;
 				eie->next = ref->inode_list;
-- 
2.34.1