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 266E8FC1D; Wed, 7 May 2025 18:45:31 +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=1746643531; cv=none; b=I78LRT7bHtrkXUaT93yZQIyIKBM1ZoZ+njnG50kngPabK503TE+9BB4vJDcz9p7xjJgmHybar+TDnI+2BkYsYFk3BgMYE2bqGYZOWwAyH3Vzo3WX0gY0ur9blQycNZWYmVEe8k6Q64gbM5D93N6bmyWk1WMFPEz/8SHzGhK3trQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746643531; c=relaxed/simple; bh=eAOh55FGJGu1RV5ITjUutC22YCp8GFes0Vlx0TPLLpk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=J2aQwxreF8Q6IlbUB7IiaevpCusbCuGTRLi1wB3hTTepC45gP5XMsy/IBl2oOXsW9OaWL0p1DdCReX1rtPisrviNKcYjp2TQEaZPvlPe7NMwMbMBDg/ZRRVyQYNPg00tedxUCJ78BmgsT4uY55d+f751FYOO/iew8h04VXMHkKA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=XCIwtubD; 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="XCIwtubD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A9F03C4CEE2; Wed, 7 May 2025 18:45:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1746643531; bh=eAOh55FGJGu1RV5ITjUutC22YCp8GFes0Vlx0TPLLpk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XCIwtubDJUq48r/HOLxg9VM7TF7Oh5A5jQMGZlSp6qSj+vtJMTCv5aRE3w4MNiLWG 76KdI/qLalBTSyMynq3B9XbXxS0Xfzuuh4wuxSVCBLz6maOjLqz9k3Wv7DXllJYab/ b1PTJtiViLpgdyciyX3UcBLp6ZigPuU0b1zU1qT0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Wengang Wang , "Darrick J. Wong" , Chandan Babu R , Leah Rumancik Subject: [PATCH 6.1 35/97] xfs: make sure sb_fdblocks is non-negative Date: Wed, 7 May 2025 20:39:10 +0200 Message-ID: <20250507183808.405884105@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250507183806.987408728@linuxfoundation.org> References: <20250507183806.987408728@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Wengang Wang [ Upstream commit 58f880711f2ba53fd5e959875aff5b3bf6d5c32e ] A user with a completely full filesystem experienced an unexpected shutdown when the filesystem tried to write the superblock during runtime. kernel shows the following dmesg: [ 8.176281] XFS (dm-4): Metadata corruption detected at xfs_sb_write_verify+0x60/0x120 [xfs], xfs_sb block 0x0 [ 8.177417] XFS (dm-4): Unmount and run xfs_repair [ 8.178016] XFS (dm-4): First 128 bytes of corrupted metadata buffer: [ 8.178703] 00000000: 58 46 53 42 00 00 10 00 00 00 00 00 01 90 00 00 XFSB............ [ 8.179487] 00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ [ 8.180312] 00000020: cf 12 dc 89 ca 26 45 29 92 e6 e3 8d 3b b8 a2 c3 .....&E)....;... [ 8.181150] 00000030: 00 00 00 00 01 00 00 06 00 00 00 00 00 00 00 80 ................ [ 8.182003] 00000040: 00 00 00 00 00 00 00 81 00 00 00 00 00 00 00 82 ................ [ 8.182004] 00000050: 00 00 00 01 00 64 00 00 00 00 00 04 00 00 00 00 .....d.......... [ 8.182004] 00000060: 00 00 64 00 b4 a5 02 00 02 00 00 08 00 00 00 00 ..d............. [ 8.182005] 00000070: 00 00 00 00 00 00 00 00 0c 09 09 03 17 00 00 19 ................ [ 8.182008] XFS (dm-4): Corruption of in-memory data detected. Shutting down filesystem [ 8.182010] XFS (dm-4): Please unmount the filesystem and rectify the problem(s) When xfs_log_sb writes super block to disk, b_fdblocks is fetched from m_fdblocks without any lock. As m_fdblocks can experience a positive -> negative -> positive changing when the FS reaches fullness (see xfs_mod_fdblocks). So there is a chance that sb_fdblocks is negative, and because sb_fdblocks is type of unsigned long long, it reads super big. And sb_fdblocks being bigger than sb_dblocks is a problem during log recovery, xfs_validate_sb_write() complains. Fix: As sb_fdblocks will be re-calculated during mount when lazysbcount is enabled, We just need to make xfs_validate_sb_write() happy -- make sure sb_fdblocks is not nenative. This patch also takes care of other percpu counters in xfs_log_sb. Signed-off-by: Wengang Wang Reviewed-by: Darrick J. Wong Signed-off-by: Chandan Babu R Signed-off-by: Leah Rumancik Acked-by: "Darrick J. Wong" Signed-off-by: Greg Kroah-Hartman --- fs/xfs/libxfs/xfs_sb.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/fs/xfs/libxfs/xfs_sb.c +++ b/fs/xfs/libxfs/xfs_sb.c @@ -1022,11 +1022,12 @@ xfs_log_sb( * and hence we don't need have to update it here. */ if (xfs_has_lazysbcount(mp)) { - mp->m_sb.sb_icount = percpu_counter_sum(&mp->m_icount); + mp->m_sb.sb_icount = percpu_counter_sum_positive(&mp->m_icount); mp->m_sb.sb_ifree = min_t(uint64_t, - percpu_counter_sum(&mp->m_ifree), + percpu_counter_sum_positive(&mp->m_ifree), mp->m_sb.sb_icount); - mp->m_sb.sb_fdblocks = percpu_counter_sum(&mp->m_fdblocks); + mp->m_sb.sb_fdblocks = + percpu_counter_sum_positive(&mp->m_fdblocks); } xfs_sb_to_disk(bp->b_addr, &mp->m_sb);