From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3B202355049 for ; Tue, 17 Feb 2026 12:53:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771332784; cv=none; b=mX23ZynJOTVLuMuS6Lqn9XcIFVrCFMr7gRcvQwj+3UZXvP44NiU4Ir9MvFMw1BgVjdauiUQUOq4IyqmWJgqbDMoq8Yu12agw5CuhCA7Z4M4VA1H87a9TByhpEIfek65P3K6YiXRdgyM1GW4UhHniEFtXNOdS5qqUNLGgxL6rcug= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771332784; c=relaxed/simple; bh=M81JYG/Mu8vqN+HzNioklfXPd+S9WwW+cZ2KjHM3NLg=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=mBB6ZqECz6alKDGPEervqD75zOuN+MJzRFMOLb83oPU9qwpmZaMWc47i+vlAIfYJFI67uGmljLCe33tskbdwHBSMsNYJznQUTQO4cY+aXgLAC14jDTOU1j5OL8Yj14Q2GW6w2YeleNEmAv6xXkzoUNgrEqv+8vscbmWjayT2G8U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zJiC7TFi; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="zJiC7TFi" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A02F4C4CEF7; Tue, 17 Feb 2026 12:53:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1771332784; bh=M81JYG/Mu8vqN+HzNioklfXPd+S9WwW+cZ2KjHM3NLg=; h=Subject:To:Cc:From:Date:From; b=zJiC7TFiPA6yvd1IkTQpHv5+0I+if9SwpIICbtEiQjLVe5gs0dTjp0B+t07NF9zHk 4MiwTdDcShvv50o8i7Ah7Z7IqIGtXSYYA3WIjx+6GMoxKiAz3kJ8fnYU/eSxtI3FEX 3i0m9cf7kZXgPnmfyVQW2v3hWq/7UHGjVXUOPpBQ= Subject: FAILED: patch "[PATCH] f2fs: fix to avoid mapping wrong physical block for swapfile" failed to apply to 6.6-stable tree To: chao@kernel.org,daehojeong@google.com,guoxiaolong2008@gmail.com,jaegeuk@kernel.org Cc: From: Date: Tue, 17 Feb 2026 13:53:00 +0100 Message-ID: <2026021700-wrongness-undermine-54e0@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 5c145c03188bc9ba1c29e0bc4d527a5978fc47f9 # git commit -s git send-email --to '' --in-reply-to '2026021700-wrongness-undermine-54e0@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 5c145c03188bc9ba1c29e0bc4d527a5978fc47f9 Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Tue, 13 Jan 2026 14:22:29 +0800 Subject: [PATCH] f2fs: fix to avoid mapping wrong physical block for swapfile Xiaolong Guo reported a f2fs bug in bugzilla [1] [1] https://bugzilla.kernel.org/show_bug.cgi?id=220951 Quoted: "When using stress-ng's swap stress test on F2FS filesystem with kernel 6.6+, the system experiences data corruption leading to either: 1 dm-verity corruption errors and device reboot 2 F2FS node corruption errors and boot hangs The issue occurs specifically when: 1 Using F2FS filesystem (ext4 is unaffected) 2 Swapfile size is less than F2FS section size (2MB) 3 Swapfile has fragmented physical layout (multiple non-contiguous extents) 4 Kernel version is 6.6+ (6.1 is unaffected) The root cause is in check_swap_activate() function in fs/f2fs/data.c. When the first extent of a small swapfile (< 2MB) is not aligned to section boundaries, the function incorrectly treats it as the last extent, failing to map subsequent extents. This results in incorrect swap_extent creation where only the first extent is mapped, causing subsequent swap writes to overwrite wrong physical locations (other files' data). Steps to Reproduce 1 Setup a device with F2FS-formatted userdata partition 2 Compile stress-ng from https://github.com/ColinIanKing/stress-ng 3 Run swap stress test: (Android devices) adb shell "cd /data/stressng; ./stress-ng-64 --metrics-brief --timeout 60 --swap 0" Log: 1 Ftrace shows in kernel 6.6, only first extent is mapped during second f2fs_map_blocks call in check_swap_activate(): stress-ng-swap-8990: f2fs_map_blocks: ino=11002, file offset=0, start blkaddr=0x43143, len=0x1 (Only 4KB mapped, not the full swapfile) 2 in kernel 6.1, both extents are correctly mapped: stress-ng-swap-5966: f2fs_map_blocks: ino=28011, file offset=0, start blkaddr=0x13cd4, len=0x1 stress-ng-swap-5966: f2fs_map_blocks: ino=28011, file offset=1, start blkaddr=0x60c84b, len=0xff The problematic code is in check_swap_activate(): if ((pblock - SM_I(sbi)->main_blkaddr) % blks_per_sec || nr_pblocks % blks_per_sec || !f2fs_valid_pinned_area(sbi, pblock)) { bool last_extent = false; not_aligned++; nr_pblocks = roundup(nr_pblocks, blks_per_sec); if (cur_lblock + nr_pblocks > sis->max) nr_pblocks -= blks_per_sec; /* this extent is last one */ if (!nr_pblocks) { nr_pblocks = last_lblock - cur_lblock; last_extent = true; } ret = f2fs_migrate_blocks(inode, cur_lblock, nr_pblocks); if (ret) { if (ret == -ENOENT) ret = -EINVAL; goto out; } if (!last_extent) goto retry; } When the first extent is unaligned and roundup(nr_pblocks, blks_per_sec) exceeds sis->max, we subtract blks_per_sec resulting in nr_pblocks = 0. The code then incorrectly assumes this is the last extent, sets nr_pblocks = last_lblock - cur_lblock (entire swapfile), and performs migration. After migration, it doesn't retry mapping, so subsequent extents are never processed. " In order to fix this issue, we need to lookup block mapping info after we migrate all blocks in the tail of swapfile. Cc: stable@kernel.org Fixes: 9703d69d9d15 ("f2fs: support file pinning for zoned devices") Cc: Daeho Jeong Reported-and-tested-by: Xiaolong Guo Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220951 Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 3c2af0ef62bb..4e2f10bd2b07 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -4206,6 +4206,7 @@ static int check_swap_activate(struct swap_info_struct *sis, while (cur_lblock < last_lblock && cur_lblock < sis->max) { struct f2fs_map_blocks map; + bool last_extent = false; retry: cond_resched(); @@ -4231,11 +4232,10 @@ static int check_swap_activate(struct swap_info_struct *sis, pblock = map.m_pblk; nr_pblocks = map.m_len; - if ((pblock - SM_I(sbi)->main_blkaddr) % blks_per_sec || - nr_pblocks % blks_per_sec || - f2fs_is_sequential_zone_area(sbi, pblock)) { - bool last_extent = false; - + if (!last_extent && + ((pblock - SM_I(sbi)->main_blkaddr) % blks_per_sec || + nr_pblocks % blks_per_sec || + f2fs_is_sequential_zone_area(sbi, pblock))) { not_aligned++; nr_pblocks = roundup(nr_pblocks, blks_per_sec); @@ -4256,8 +4256,8 @@ static int check_swap_activate(struct swap_info_struct *sis, goto out; } - if (!last_extent) - goto retry; + /* lookup block mapping info after block migration */ + goto retry; } if (cur_lblock + nr_pblocks >= sis->max)