3.16.85-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Theodore Ts'o <tytso@xxxxxxx>
commit 170417c8c7bb2cbbdd949bf5c443c0c8f24a203b upstream.
Commit 345c0dbf3a30 ("ext4: protect journal inode's blocks using
block_validity") failed to add an exception for the journal inode in
ext4_check_blockref(), which is the function used by ext4_get_branch()
for indirect blocks. This caused attempts to read from the ext3-style
journals to fail with:
[ 848.968550] EXT4-fs error (device sdb7): ext4_get_branch:171: inode #8: block 30343695: comm jbd2/sdb7-8: invalid block
Fix this by adding the missing exception check.
Fixes: 345c0dbf3a30 ("ext4: protect journal inode's blocks using block_validity")
Reported-by: Arthur Marsh <arthur.marsh@xxxxxxxxxxxxxxxx>
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
[bwh: Backported to 3.16: Use EXT4_HAS_COMPAT_FEATURE]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
--- a/fs/ext4/block_validity.c
+++ b/fs/ext4/block_validity.c
@@ -277,6 +277,12 @@ int ext4_check_blockref(const char *func
__le32 *bref = p;
unsigned int blk;
+ if (EXT4_HAS_COMPAT_FEATURE(inode->i_sb,
+ EXT4_FEATURE_COMPAT_HAS_JOURNAL) &&
+ (inode->i_ino ==
+ le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_journal_inum)))
+ return 0;
+
while (bref < p+max) {
blk = le32_to_cpu(*bref++);
if (blk &&
