Re: [PATCH 6.1.y] ext4: filesystems without casefold feature cannot be mounted with siphash

[Sasha Levin <sashal@kernel.org>]

[ Sasha's backport helper bot ]

Hi,

✅ All tests passed successfully. No issues detected.
No action required from the submitter.

The upstream commit SHA1 provided is correct: 985b67cd86392310d9e9326de941c22fc9340eec

WARNING: Author mismatch between patch and upstream commit:
Backport author: <miguelgarciaroman8@gmail.com>
Commit author: Lizhi Xu<lizhi.xu@windriver.com>

Status in newer kernel trees:
6.14.y | Present (exact SHA1)
6.13.y | Present (exact SHA1)
6.12.y | Present (exact SHA1)
6.6.y | Not found

Note: The patch differs from the upstream commit:
---
1:  985b67cd86392 ! 1:  18c15fd3e33df ext4: filesystems without casefold feature cannot be mounted with siphash
    @@ Metadata
      ## Commit message ##
         ext4: filesystems without casefold feature cannot be mounted with siphash
     
    +    commit 985b67cd86392310d9e9326de941c22fc9340eec upstream.
    +
    +    This patch is a backport.
    +
         When mounting the ext4 filesystem, if the default hash version is set to
         DX_HASH_SIPHASH but the casefold feature is not set, exit the mounting.
     
    -    Reported-by: syzbot+340581ba9dceb7e06fb3@syzkaller.appspotmail.com
    +    Reported-by: syzbot+9177d065333561cd6fd0@syzkaller.appspotmail.com
    +    Bug: https://syzkaller.appspot.com/bug?extid=9177d065333561cd6fd0
         Signed-off-by: Lizhi Xu <lizhi.xu@windriver.com>
         Link: https://patch.msgid.link/20240605012335.44086-1-lizhi.xu@windriver.com
         Signed-off-by: Theodore Ts'o <tytso@mit.edu>
    +    Signed-off-by: Miguel Garcia Roman <miguelgarciaroman8@gmail.com>
    +    (cherry picked from commit 985b67cd86392310d9e9326de941c22fc9340eec)
     
      ## fs/ext4/super.c ##
     @@ fs/ext4/super.c: int ext4_feature_set_ok(struct super_block *sb, int readonly)
    - 			 "mounted without CONFIG_UNICODE");
      		return 0;
      	}
    + #endif
     +	if (EXT4_SB(sb)->s_es->s_def_hash_version == DX_HASH_SIPHASH &&
     +	    !ext4_has_feature_casefold(sb)) {
     +		ext4_msg(sb, KERN_ERR,
    -+			 "Filesystem without casefold feature cannot be "
    -+			 "mounted with siphash");
    ++			 "Filesystem without casefold feature cannot be mounted with siphash");
     +		return 0;
     +	}
      
---

Results of testing on various branches:

| Branch                    | Patch Apply | Build Test |
|---------------------------|-------------|------------|
| stable/linux-6.1.y        |  Success    |  Success   |