[PATCH] ext4: do not BUG when INLINE_DATA_FL lacks system.data xattr

[Theodore Ts'o]

A syzbot fuzzed image triggered a BUG_ON in ext4_update_inline_data()
when an inode had the INLINE_DATA_FL flag set but was missing the
system.data extended attribute.

Since this can happen due to a maiciouly fuzzed file system, we
shouldn't BUG, but rather, report it as a corrupted file system.

Reported-by: syzbot+544248a761451c0df72f@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
---
 fs/ext4/inline.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index d5b32d242495..424c40c768de 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -354,6 +354,12 @@ static int ext4_update_inline_data(handle_t *handle, struct inode *inode,
 	if (error)
 		goto out;
 
+	if (is.s.not_found) {
+		EXT4_ERROR_INODE(inode, "missing inline data xattr");
+		error = -EFSCORRUPTED;
+		goto out;
+	}
+
 	BUG_ON(is.s.not_found);
 
 	len -= EXT4_MIN_INLINE_DATA_SIZE;
-- 
2.47.2