Re: [PATCH] ext4: fix null-ptr-deref in ext4_write_info

[Theodore Ts'o]

On Fri, 5 Aug 2022 20:39:47 +0800, Baokun Li wrote:
> I caught a null-ptr-deref bug as follows:
> ==================================================================
> KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f]
> CPU: 1 PID: 1589 Comm: umount Not tainted 5.10.0-02219-dirty #339
> RIP: 0010:ext4_write_info+0x53/0x1b0
> [...]
> Call Trace:
>  dquot_writeback_dquots+0x341/0x9a0
>  ext4_sync_fs+0x19e/0x800
>  __sync_filesystem+0x83/0x100
>  sync_filesystem+0x89/0xf0
>  generic_shutdown_super+0x79/0x3e0
>  kill_block_super+0xa1/0x110
>  deactivate_locked_super+0xac/0x130
>  deactivate_super+0xb6/0xd0
>  cleanup_mnt+0x289/0x400
>  __cleanup_mnt+0x16/0x20
>  task_work_run+0x11c/0x1c0
>  exit_to_user_mode_prepare+0x203/0x210
>  syscall_exit_to_user_mode+0x5b/0x3a0
>  do_syscall_64+0x59/0x70
>  entry_SYSCALL_64_after_hwframe+0x44/0xa9
>  ==================================================================
> 
> [...]

Applied, thanks!

[1/1] ext4: fix null-ptr-deref in ext4_write_info
      commit: 647642bf8f326994d7eaf785bba3fa9dad92cff0

Best regards,
-- 
Theodore Ts'o <tytso@xxxxxxx>