Re: [PATCH v2] f2fs: initialize ino_entry_info before checkpoint load

[Deepanshu Kartikey]

On Sun, May 10, 2026 at 9:53 AM Deepanshu Kartikey
<kartikey406@xxxxxxxxx> wrote:
>
> When f2fs_get_valid_checkpoint() fails during mount (e.g. due to an
> invalid checkpoint CRC on a malformed image), f2fs_fill_super() takes
> an error path that eventually calls iput() on the root inode. This
> invokes f2fs_drop_inode() -> f2fs_exist_written_data(), which acquires
> sbi->im[]->ino_lock. However, f2fs_init_ino_entry_info() has not run
> yet at this point, so the spinlock is uninitialized and lockdep
> complains:
>
>   F2FS-fs (loop0): invalid crc value
>   F2FS-fs (loop0): Failed to get valid F2FS checkpoint
>   INFO: trying to register non-static key.
>   The code is fine but needs lockdep annotation, or maybe
>   you didn't initialize this object before use?
>   ...
>    f2fs_exist_written_data+0x53/0x90 fs/f2fs/checkpoint.c:787
>    f2fs_drop_inode+0xda/0xbf0 fs/f2fs/super.c:1852
>    iput+0x651/0xe80 fs/inode.c:2009
>    f2fs_fill_super+0x6047/0x7850 fs/f2fs/super.c:5461
>
> Move f2fs_init_ino_entry_info() to before f2fs_get_valid_checkpoint()
> so that sbi->im[] is always fully initialized before any error path
> can trigger iput() -> f2fs_drop_inode(). The init function only
> depends on raw superblock fields (BLKS_PER_SEG, F2FS_CP_PACKS,
> NR_CURSEG_PERSIST_TYPE, __cp_payload), which are populated well
> before checkpoint load, so the move is safe.
>
> Fixes: 3063c80776e3 ("f2fs: another way to set large folio by remembering inode number")
> Cc: stable@xxxxxxxxxx
> Reported-by: syzbot+eec8f2693d71386bd600@xxxxxxxxxxxxxxxxxxxxxxxxx
> Closes: https://syzkaller.appspot.com/bug?extid=eec8f2693d71386bd600
> Tested-by: syzbot+eec8f2693d71386bd600@xxxxxxxxxxxxxxxxxxxxxxxxx
> Signed-off-by: Deepanshu Kartikey <kartikey406@xxxxxxxxx>
> ---
> Changes in v2:
>  - Add Fixes: tag (suggested by Chao Yu)
>  - Add Cc: stable@xxxxxxxxxx
> ---
>  fs/f2fs/super.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> index c6afdbd6e1cd..6a231a5b0d62 100644
> --- a/fs/f2fs/super.c
> +++ b/fs/f2fs/super.c
> @@ -5140,6 +5140,13 @@ static int f2fs_fill_super(struct super_block *sb, struct fs_context *fc)
>                 goto free_page_array_cache;
>         }
>
> +       /*
> +        * Initialize ino entry info early so f2fs_drop_inode ->
> +        * f2fs_exist_written_data can safely take im->ino_lock if mount
> +        * fails after this point and triggers iput on cleanup.
> +        */
> +       f2fs_init_ino_entry_info(sbi);
> +
>         err = f2fs_get_valid_checkpoint(sbi);
>         if (err) {
>                 f2fs_err(sbi, "Failed to get valid F2FS checkpoint");
> @@ -5184,8 +5191,6 @@ static int f2fs_fill_super(struct super_block *sb, struct fs_context *fc)
>
>         f2fs_init_extent_cache_info(sbi);
>
> -       f2fs_init_ino_entry_info(sbi);
> -
>         f2fs_init_fsync_node_info(sbi);
>
>         /* setup checkpoint request control and start checkpoint issue thread */
> --
> 2.43.0
>

Hi Chao,

Please let me know the status of this patch. This is already "Reviewed-by:" you.

Please let me know if anything needed from my side.

Thanks

Deepanshu Kartikey