On Fri 01-01-21 17:03:21, Jinoh Kang wrote:
> From: Jan Kara <jack@xxxxxxx>
>
> commit b08070eca9e247f60ab39d79b2c25d274750441f upstream.
>
> ext4_handle_error() with errors=continue mount option can accidentally
> remount the filesystem read-only when the system is rebooting. Fix that.
>
> Fixes: 1dc1097ff60e ("ext4: avoid panic during forced reboot")
> Signed-off-by: Jan Kara <jack@xxxxxxx>
> Reviewed-by: Andreas Dilger <adilger@xxxxxxxxx>
> Cc: stable@xxxxxxxxxx
> Link: https://lore.kernel.org/r/20201127113405.26867-2-jack@xxxxxxx
> Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
> [jinoh: backport accounting for missing
> commit 9b5f6c9b83d9 ("ext4: make s_mount_flags modifications atomic")]
> Signed-off-by: Jinoh Kang <jinoh.kang.kr@xxxxxxxxx>
> ---
> v1 --> v2: added missing comment and signoff
> Apologies for wasted traffic...
>
> Please disregard the previous mail, which was in a wrong thread:
> - <5611c936-5913-d570-36a4-2b2ed209cd88@xxxxxxxxx> [PATCH 5.4 bp]
> That said, the patches for 4.19 and 5.4 have the same patch ID.
The backport looks good to me. Thanks!
Honza
> ---
> fs/ext4/super.c | 14 ++++++--------
> 1 file changed, 6 insertions(+), 8 deletions(-)
>
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index 920658ca8777..06568467b0c2 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -455,19 +455,17 @@ static bool system_going_down(void)
>
> static void ext4_handle_error(struct super_block *sb)
> {
> + journal_t *journal = EXT4_SB(sb)->s_journal;
> +
> if (test_opt(sb, WARN_ON_ERROR))
> WARN_ON_ONCE(1);
>
> - if (sb_rdonly(sb))
> + if (sb_rdonly(sb) || test_opt(sb, ERRORS_CONT))
> return;
>
> - if (!test_opt(sb, ERRORS_CONT)) {
> - journal_t *journal = EXT4_SB(sb)->s_journal;
> -
> - EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
> - if (journal)
> - jbd2_journal_abort(journal, -EIO);
> - }
> + EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
> + if (journal)
> + jbd2_journal_abort(journal, -EIO);
> /*
> * We force ERRORS_RO behavior when system is rebooting. Otherwise we
> * could panic during 'reboot -f' as the underlying device got already
> --
> 2.26.2
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
