This is a note to let you know that I've just added the patch titled
ext4: improve error recovery code paths in __ext4_remount()
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ext4-improve-error-recovery-code-paths-in-__ext4_remount.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 4c0b4818b1f636bc96359f7817a2d8bab6370162 Mon Sep 17 00:00:00 2001
From: Theodore Ts'o <tytso@xxxxxxx>
Date: Fri, 5 May 2023 22:20:29 -0400
Subject: ext4: improve error recovery code paths in __ext4_remount()
From: Theodore Ts'o <tytso@xxxxxxx>
commit 4c0b4818b1f636bc96359f7817a2d8bab6370162 upstream.
If there are failures while changing the mount options in
__ext4_remount(), we need to restore the old mount options.
This commit fixes two problem. The first is there is a chance that we
will free the old quota file names before a potential failure leading
to a use-after-free. The second problem addressed in this commit is
if there is a failed read/write to read-only transition, if the quota
has already been suspended, we need to renable quota handling.
Cc: stable@xxxxxxxxxx
Link: https://lore.kernel.org/r/20230506142419.984260-2-tytso@xxxxxxx
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ext4/super.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -5985,9 +5985,6 @@ static int ext4_remount(struct super_blo
}
#ifdef CONFIG_QUOTA
- /* Release old quota file names */
- for (i = 0; i < EXT4_MAXQUOTAS; i++)
- kfree(old_opts.s_qf_names[i]);
if (enable_quota) {
if (sb_any_quota_suspended(sb))
dquot_resume(sb, -1);
@@ -5997,6 +5994,9 @@ static int ext4_remount(struct super_blo
goto restore_opts;
}
}
+ /* Release old quota file names */
+ for (i = 0; i < EXT4_MAXQUOTAS; i++)
+ kfree(old_opts.s_qf_names[i]);
#endif
if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
ext4_release_system_zone(sb);
@@ -6017,6 +6017,13 @@ static int ext4_remount(struct super_blo
return 0;
restore_opts:
+ /*
+ * If there was a failing r/w to ro transition, we may need to
+ * re-enable quota
+ */
+ if ((sb->s_flags & SB_RDONLY) && !(old_sb_flags & SB_RDONLY) &&
+ sb_any_quota_suspended(sb))
+ dquot_resume(sb, -1);
sb->s_flags = old_sb_flags;
sbi->s_mount_opt = old_opts.s_mount_opt;
sbi->s_mount_opt2 = old_opts.s_mount_opt2;
Patches currently in stable-queue which might be from tytso@xxxxxxx are
queue-5.15/ext4-improve-error-recovery-code-paths-in-__ext4_remount.patch
queue-5.15/ext4-fix-warning-in-mb_find_extent.patch
queue-5.15/ext4-fix-deadlock-when-converting-an-inline-directory-in-nojournal-mode.patch
queue-5.15/ext4-bail-out-of-ext4_xattr_ibody_get-fails-for-any-reason.patch
queue-5.15/ext4-improve-error-handling-from-ext4_dirhash.patch
queue-5.15/ext4-add-bounds-checking-in-get_max_inline_xattr_value_size.patch
queue-5.15/ext4-avoid-a-potential-slab-out-of-bounds-in-ext4_group_desc_csum.patch
queue-5.15/ext4-check-iomap-type-only-if-ext4_iomap_begin-does-not-fail.patch
queue-5.15/ext4-fix-invalid-free-tracking-in-ext4_xattr_move_to_block.patch
queue-5.15/ext4-remove-a-bug_on-in-ext4_mb_release_group_pa.patch
queue-5.15/ext4-fix-data-races-when-using-cached-status-extents.patch
