@@ -191,7 +191,7 @@ setversion_out:
case EXT4_IOC_GROUP_EXTEND: {
ext4_fsblk_t n_blocks_count;
struct super_block *sb = inode->i_sb;
- int err, err2;
+ int err, err2=0;
if (!capable(CAP_SYS_RESOURCE))
return -EPERM;
@@ -204,9 +204,11 @@ setversion_out:
return err;
err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
- jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
- err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
- jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
+ if (EXT4_SB(sb)->s_journal) {
+ jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
+ err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
+ jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
+ }
if (err == 0)
err = err2;
mnt_drop_write(filp->f_path.mnt);
@@ -216,7 +218,7 @@ setversion_out:
case EXT4_IOC_GROUP_ADD: {
struct ext4_new_group_data input;
struct super_block *sb = inode->i_sb;
- int err, err2;
+ int err, err2=0;
if (!capable(CAP_SYS_RESOURCE))
return -EPERM;
@@ -230,9 +232,11 @@ setversion_out:
return err;
err = ext4_group_add(sb, &input);
- jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
- err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
- jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
+ if (EXT4_SB(sb)->s_journal) {
+ jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
+ err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
+ jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
+ }
if (err == 0)
err = err2;
mnt_drop_write(filp->f_path.mnt);
EXT4_IOC_GROUP_ADD and EXT4_IOC_GROUP_EXTEND ioctls should not flush journal in no_journal mode. This can be triggered by running resize2fs on a mounted no_journal partition as follows: mkfs.ext4 /dev/sdb1 -O ^has_journal enlarge /dev/sdb1 in partition table mount /dev/sdb1 resize2fs /dev/sdb1 And it will get these error message: BUG: unable to handle kernel NULL pointer dereference at 00000014 IP: [<c039d282>] _spin_lock+0x8/0x19 *pde = 00000000 Oops: 0002 [#1] SMP Signed-off-by: Peng Tao <bergwolf@gmail.com> --- fs/ext4/ioctl.c | 20 ++++++++++++-------- 1 files changed, 12 insertions(+), 8 deletions(-)