diff options
| author | Ojaswin Mujoo <ojaswin@linux.ibm.com> | 2024-08-30 12:50:57 +0530 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2024-09-03 22:14:17 -0400 |
| commit | ee85e0938aa8f9846d21e4d302c3cf6a2a75110d (patch) | |
| tree | 5817663212fb77922746c912e98048f3fa652ee1 /fs/ext4 | |
| parent | cc749e61c011c255d81b192a822db650c68b313f (diff) | |
ext4: check stripe size compatibility on remount as well
We disable stripe size in __ext4_fill_super if it is not a multiple of
the cluster ratio however this check is missed when trying to remount.
This can leave us with cases where stripe < cluster_ratio after
remount:set making EXT4_B2C(sbi->s_stripe) become 0 that can cause some
unforeseen bugs like divide by 0.
Fix that by adding the check in remount path as well.
Reported-by: syzbot+1ad8bac5af24d01e2cbd@syzkaller.appspotmail.com
Tested-by: syzbot+1ad8bac5af24d01e2cbd@syzkaller.appspotmail.com
Reviewed-by: Kemeng Shi <shikemeng@huaweicloud.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Fixes: c3defd99d58c ("ext4: treat stripe in block unit")
Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Link: https://patch.msgid.link/3a493bb503c3598e25dcfbed2936bb2dff3fece7.1725002410.git.ojaswin@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'fs/ext4')
| -rw-r--r-- | fs/ext4/super.c | 29 |
1 files changed, 22 insertions, 7 deletions
diff --git a/fs/ext4/super.c b/fs/ext4/super.c index adc5046fe9dd..16a4ce704460 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -5178,6 +5178,18 @@ static int ext4_block_group_meta_init(struct super_block *sb, int silent) return 0; } +/* + * It's hard to get stripe aligned blocks if stripe is not aligned with + * cluster, just disable stripe and alert user to simplify code and avoid + * stripe aligned allocation which will rarely succeed. + */ +static bool ext4_is_stripe_incompatible(struct super_block *sb, unsigned long stripe) +{ + struct ext4_sb_info *sbi = EXT4_SB(sb); + return (stripe > 0 && sbi->s_cluster_ratio > 1 && + stripe % sbi->s_cluster_ratio != 0); +} + static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb) { struct ext4_super_block *es = NULL; @@ -5287,13 +5299,7 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb) goto failed_mount3; sbi->s_stripe = ext4_get_stripe_size(sbi); - /* - * It's hard to get stripe aligned blocks if stripe is not aligned with - * cluster, just disable stripe and alert user to simpfy code and avoid - * stripe aligned allocation which will rarely successes. - */ - if (sbi->s_stripe > 0 && sbi->s_cluster_ratio > 1 && - sbi->s_stripe % sbi->s_cluster_ratio != 0) { + if (ext4_is_stripe_incompatible(sb, sbi->s_stripe)) { ext4_msg(sb, KERN_WARNING, "stripe (%lu) is not aligned with cluster size (%u), " "stripe is disabled", @@ -6457,6 +6463,15 @@ static int __ext4_remount(struct fs_context *fc, struct super_block *sb) } + if ((ctx->spec & EXT4_SPEC_s_stripe) && + ext4_is_stripe_incompatible(sb, ctx->s_stripe)) { + ext4_msg(sb, KERN_WARNING, + "stripe (%lu) is not aligned with cluster size (%u), " + "stripe is disabled", + ctx->s_stripe, sbi->s_cluster_ratio); + ctx->s_stripe = 0; + } + /* * Changing the DIOREAD_NOLOCK or DELALLOC mount options may cause * two calls to ext4_should_dioread_nolock() to return inconsistent |