ext4: Replace open coded mdata csum feature to helper function
Besides the fact that this replacement improves code readability
it also protects from errors caused direct EXT4_S(sb)->s_es manipulation
which may result attempt to use uninitialized csum machinery.
#Testcase_BEGIN
IMG=/dev/ram0
MNT=/mnt
mkfs.ext4 $IMG
mount $IMG $MNT
#Enable feature directly on disk, on mounted fs
tune2fs -O metadata_csum $IMG
# Provoke metadata update, likey result in OOPS
touch $MNT/test
umount $MNT
#Testcase_END
# Replacement script
@@
expression E;
@@
- EXT4_HAS_RO_COMPAT_FEATURE(E, EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)
+ ext4_has_metadata_csum(E)
https://bugzilla.kernel.org/show_bug.cgi?id=82201
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index 42823ab..1e09fc7 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -142,8 +142,7 @@
sector_t block_nr,
struct ext4_xattr_header *hdr)
{
- if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
- EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
+ if (ext4_has_metadata_csum(inode->i_sb) &&
(hdr->h_checksum != ext4_xattr_block_csum(inode, block_nr, hdr)))
return 0;
return 1;
@@ -153,8 +152,7 @@
sector_t block_nr,
struct ext4_xattr_header *hdr)
{
- if (!EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
- EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
+ if (!ext4_has_metadata_csum(inode->i_sb))
return;
hdr->h_checksum = ext4_xattr_block_csum(inode, block_nr, hdr);