Re: [PATCH v14 7/9] f2fs: Log error when lookup of encoded dentry fails
From: Gabriel Krisman Bertazi
Date: Fri Mar 22 2024 - 18:11:40 EST
Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx> writes:
> If the volume is in strict mode, generi c_ci_compare can report a broken
> encoding name. This will not trigger on a bad lookup, which is caught
> earlier, only if the actual disk name is bad.
>
> Suggested-by: Gabriel Krisman Bertazi <krisman@xxxxxxx>
> Signed-off-by: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>
> ---
> fs/f2fs/dir.c | 21 ++++++++++++++++-----
> 1 file changed, 16 insertions(+), 5 deletions(-)
>
> diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
> index 88b0045d0c4f..3b0003e8767a 100644
> --- a/fs/f2fs/dir.c
> +++ b/fs/f2fs/dir.c
> @@ -192,11 +192,22 @@ static inline int f2fs_match_name(const struct inode *dir,
> struct fscrypt_name f;
>
> #if IS_ENABLED(CONFIG_UNICODE)
> - if (fname->cf_name.name)
> - return generic_ci_match(dir, fname->usr_fname,
> - &fname->cf_name,
> - de_name, de_name_len);
> -
> + if (fname->cf_name.name) {
> + int ret = generic_ci_match(dir, fname->usr_fname,
> + &fname->cf_name,
> + de_name, de_name_len);
> + if (ret < 0) {
> + /*
> + * Treat comparison errors as not a match. The
> + * only case where it happens is on a disk
> + * corruption or ENOMEM.
> + */
> + if (ret == -EINVAL)
> + f2fs_warn(F2FS_SB(dir->i_sb),
> + "Directory contains filename that is invalid UTF-8");
> + }
> + return ret;
No point in checking ret < 0 and then ret == -EINVAL. just check for
-EINVAL. That was ok in ext4 because we actually need to change ret to
false.
> + }
> #endif
> f.usr_fname = fname->usr_fname;
> f.disk_name = fname->disk_name;
--
Gabriel Krisman Bertazi