1 ext4: fix unjournalled bg descriptor while initializing inode bitmap
3 The first time that we allocate from an uninitialized inode allocation
4 bitmap, if the block allocation bitmap is also uninitalized, we need
5 to get write access to the block group descriptor before we start
6 modifying the block group descriptor flags and updating the free block
7 count, etc. Otherwise, there is the potential of a bad journal
8 checksum (if journal checksums are enabled), and of the file system
9 becoming inconsistent if we crash at exactly the wrong time.
11 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
12 Cc: stable@vger.kernel.org
14 fs/ext4/ialloc.c | 14 +++++++-------
15 1 file changed, 7 insertions(+), 7 deletions(-)
17 diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
18 index a87455d..0840bf3 100644
19 --- a/fs/ext4/ialloc.c
20 +++ b/fs/ext4/ialloc.c
21 @@ -874,6 +874,13 @@ got:
25 + BUFFER_TRACE(group_desc_bh, "get_write_access");
26 + err = ext4_journal_get_write_access(handle, group_desc_bh);
28 + ext4_std_error(sb, err);
32 /* We may have to initialize the block bitmap if it isn't already */
33 if (ext4_has_group_desc_csum(sb) &&
34 gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) {
35 @@ -910,13 +917,6 @@ got:
39 - BUFFER_TRACE(group_desc_bh, "get_write_access");
40 - err = ext4_journal_get_write_access(handle, group_desc_bh);
42 - ext4_std_error(sb, err);
46 /* Update the relevant bg descriptor fields */
47 if (ext4_has_group_desc_csum(sb)) {