The quilt patch titled
Subject: nilfs2: fix kernel bug due to missing clearing of buffer delay flag
has been removed from the -mm tree. Its filename was
nilfs2-fix-kernel-bug-due-to-missing-clearing-of-buffer-delay-flag.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
Subject: nilfs2: fix kernel bug due to missing clearing of buffer delay flag
Date: Wed, 16 Oct 2024 06:32:07 +0900
Syzbot reported that after nilfs2 reads a corrupted file system image and
degrades to read-only, the BUG_ON check for the buffer delay flag in
submit_bh_wbc() may fail, causing a kernel bug.
This is because the buffer delay flag is not cleared when clearing the
buffer state flags to discard a page/folio or a buffer head. So, fix
this.
This became necessary when the use of nilfs2's own page clear routine was
expanded. This state inconsistency does not occur if the buffer is
written normally by log writing.
Link: https://lkml.kernel.org/r/20241015213300.7114-1-konishi.ryusuke@xxxxxxxxx
Fixes: 8c26c4e2694a ("nilfs2: fix issue with flush kernel thread after remount in RO mode because of driver's internal error or metadata corruption")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
Reported-by: syzbot+985ada84bf055a575c07@xxxxxxxxxxxxxxxxxxxxxxxxx
Closes: https://syzkaller.appspot.com/bug?extid=985ada84bf055a575c07
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/nilfs2/page.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
--- a/fs/nilfs2/page.c~nilfs2-fix-kernel-bug-due-to-missing-clearing-of-buffer-delay-flag
+++ a/fs/nilfs2/page.c
@@ -77,7 +77,8 @@ void nilfs_forget_buffer(struct buffer_h
const unsigned long clear_bits =
(BIT(BH_Uptodate) | BIT(BH_Dirty) | BIT(BH_Mapped) |
BIT(BH_Async_Write) | BIT(BH_NILFS_Volatile) |
- BIT(BH_NILFS_Checked) | BIT(BH_NILFS_Redirected));
+ BIT(BH_NILFS_Checked) | BIT(BH_NILFS_Redirected) |
+ BIT(BH_Delay));
lock_buffer(bh);
set_mask_bits(&bh->b_state, clear_bits, 0);
@@ -406,7 +407,8 @@ void nilfs_clear_folio_dirty(struct foli
const unsigned long clear_bits =
(BIT(BH_Uptodate) | BIT(BH_Dirty) | BIT(BH_Mapped) |
BIT(BH_Async_Write) | BIT(BH_NILFS_Volatile) |
- BIT(BH_NILFS_Checked) | BIT(BH_NILFS_Redirected));
+ BIT(BH_NILFS_Checked) | BIT(BH_NILFS_Redirected) |
+ BIT(BH_Delay));
bh = head;
do {
_
Patches currently in -mm which might be from konishi.ryusuke@xxxxxxxxx are
nilfs2-fix-kernel-bug-due-to-missing-clearing-of-checked-flag.patch
