[PATCH] ext4: Fix error message when rejecting the default hash
From: Gabriel Krisman Bertazi <hidden>
Date: 2024-08-27 20:16:43
Also in:
linux-ext4, linux-fscrypt, lkml, llvm, netfilter-devel, oe-kbuild-all
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
"Theodore Ts'o" [off-list ref] writes:
On Wed, 05 Jun 2024 09:23:35 +0800, Lizhi Xu wrote:quoted
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.Applied, thanks! [1/1] fs/ext4: Filesystem without casefold feature cannot be mounted with spihash commit: 985b67cd86392310d9e9326de941c22fc9340eec
Ted, Since you took the above, can you please consider the following fixup? I had pointed we shouldn't have siphash as the sb default hash at all: based on your dev branch.
8
Subject: [PATCH] ext4: Fix error message when rejecting the default hash
Commit 985b67cd8639 ("ext4: filesystems without casefold feature cannot
be mounted with siphash") properly rejects volumes where
s_def_hash_version is set to DX_HASH_SIPHASH, but the check and the
error message should not look into casefold setup - a filesystem should
never have DX_HASH_SIPHASH as the default hash. Fix it and, since we
are there, move the check to ext4_hash_info_init.
Fixes:985b67cd8639 ("ext4: filesystems without casefold feature cannot
be mounted with siphash")
Signed-off-by: Gabriel Krisman Bertazi <redacted>
---
fs/ext4/ext4.h | 1 +
fs/ext4/super.c | 27 +++++++++++++++++----------
2 files changed, 18 insertions(+), 10 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 5845e4aa091a..4120f24880cb 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h@@ -2462,6 +2462,7 @@ static inline __le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize) #define DX_HASH_HALF_MD4_UNSIGNED 4 #define DX_HASH_TEA_UNSIGNED 5 #define DX_HASH_SIPHASH 6 +#define DX_HASH_LAST DX_HASH_SIPHASH static inline u32 ext4_chksum(struct ext4_sb_info *sbi, u32 crc, const void *address, unsigned int length)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 25cd0d662e31..c6a34ad07ecc 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c@@ -3582,13 +3582,6 @@ int ext4_feature_set_ok(struct super_block *sb, int readonly) "mounted without CONFIG_UNICODE"); return 0; } - 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"); - return 0; - } if (readonly) return 1;
@@ -5094,16 +5087,27 @@ static int ext4_load_super(struct super_block *sb, ext4_fsblk_t *lsb, return ret; } -static void ext4_hash_info_init(struct super_block *sb) +static int ext4_hash_info_init(struct super_block *sb) { struct ext4_sb_info *sbi = EXT4_SB(sb); struct ext4_super_block *es = sbi->s_es; unsigned int i; + sbi->s_def_hash_version = es->s_def_hash_version; + + if (sbi->s_def_hash_version > DX_HASH_LAST) { + ext4_msg(sb, KERN_ERR, + "Invalid default hash set in the superblock"); + return -EINVAL; + } else if (sbi->s_def_hash_version == DX_HASH_SIPHASH) { + ext4_msg(sb, KERN_ERR, + "SIPHASH is not a valid default hash value"); + return -EINVAL; + } + for (i = 0; i < 4; i++) sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]); - sbi->s_def_hash_version = es->s_def_hash_version; if (ext4_has_feature_dir_index(sb)) { i = le32_to_cpu(es->s_flags); if (i & EXT2_FLAGS_UNSIGNED_HASH)
@@ -5121,6 +5125,7 @@ static void ext4_hash_info_init(struct super_block *sb) #endif } } + return 0; } static int ext4_block_group_meta_init(struct super_block *sb, int silent)
@@ -5256,7 +5261,9 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb) if (err) goto failed_mount; - ext4_hash_info_init(sb); + err = ext4_hash_info_init(sb); + if (err) + goto failed_mount; err = ext4_handle_clustersize(sb); if (err)
--
2.46.0