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 ED2F71E9B0D; Mon, 13 Oct 2025 15:37:41 +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=1760369862; cv=none; b=hH7+vlPCcYO2ceBjT7nfmXdSZ5AaUIZc3N3zOePrBgdPRAD65aJVQsYng7Ia21sLtg1UvhvnDN8TJhrXb0nJTloPrYKCu0Z8VaNjuXAmnC9hhA+eL2vViaFxyrya0h04Hed8eV4+BqauC49o1zyH1tvvl/gqeKguHHju6bJMnYc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760369862; c=relaxed/simple; bh=J0ni+ePdhT6jvaXC0DAXL5xGGjvQdp5LZ2ru2m3EH/E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lyQiyBP5D8dXNrc1VHnNEzs7/9RhS1PeqyqRV2GZ6oybHHpj46L7Ib9MZdRRwRdZB6D7DqXoDw3/nGMx75XWAnJsGEDpwiiNNvsIySXO5XlDSltDrZsmjhuyMM4LAMzvBUXJ9QNevaCaZTPEQOwivmnYB2Nfq3J90BQ+iuj44sU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=RI4pWy/U; 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="RI4pWy/U" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 789B8C4CEE7; Mon, 13 Oct 2025 15:37:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1760369861; bh=J0ni+ePdhT6jvaXC0DAXL5xGGjvQdp5LZ2ru2m3EH/E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RI4pWy/UevrKI6AeLZwmdsWfue+fkNZ02vkHzzTqSYYLze488hlUsyCR6emI+41tm TyDPVgh/n9M62xjlhenPsH+IaNh3iK/6s84A7qSAdeWeuKYTk5LZ0YBjLU13XvqZIo fIZy0iNQbOhk49qzsQpejKigIUdqfjSfWpdZ9XWs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, wangzijie , Chao Yu , Jaegeuk Kim , Sasha Levin Subject: [PATCH 6.17 377/563] f2fs: fix zero-sized extent for precache extents Date: Mon, 13 Oct 2025 16:43:58 +0200 Message-ID: <20251013144424.933567439@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251013144411.274874080@linuxfoundation.org> References: <20251013144411.274874080@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: wangzijie [ Upstream commit 8175c864391753b210f3dcfae1aeed686a226ebb ] Script to reproduce: f2fs_io write 1 0 1881 rand dsync testfile f2fs_io fallocate 0 7708672 4096 testfile f2fs_io write 1 1881 1 rand buffered testfile fsync testfile umount mount f2fs_io precache_extents testfile When the data layout is something like this: dnode1: dnode2: [0] A [0] NEW_ADDR [1] A+1 [1] 0x0 ... [1016] A+1016 [1017] B (B!=A+1017) [1017] 0x0 During precache_extents, we map the last block(valid blkaddr) in dnode1: map->m_flags |= F2FS_MAP_MAPPED; map->m_pblk = blkaddr(valid blkaddr); map->m_len = 1; then we goto next_dnode, meet the first block in dnode2(hole), goto sync_out: map->m_flags & F2FS_MAP_MAPPED == true, and we make zero-sized extent: map->m_len = 1 ofs = start_pgofs - map->m_lblk = 1882 - 1881 = 1 ei.fofs = start_pgofs = 1882 ei.len = map->m_len - ofs = 1 - 1 = 0 Rebased on patch[1], this patch can cover these cases to avoid zero-sized extent: A,B,C is valid blkaddr case1: dnode1: dnode2: [0] A [0] NEW_ADDR [1] A+1 [1] 0x0 ... .... [1016] A+1016 [1017] B (B!=A+1017) [1017] 0x0 case2: dnode1: dnode2: [0] A [0] C (C!=B+1) [1] A+1 [1] C+1 ... .... [1016] A+1016 [1017] B (B!=A+1017) [1017] 0x0 case3: dnode1: dnode2: [0] A [0] C (C!=B+2) [1] A+1 [1] C+1 ... .... [1015] A+1015 [1016] B (B!=A+1016) [1017] B+1 [1017] 0x0 [1] https://lore.kernel.org/linux-f2fs-devel/20250912081250.44383-1-chao@kernel.org/ Fixes: c4020b2da4c9 ("f2fs: support F2FS_IOC_PRECACHE_EXTENTS") Signed-off-by: wangzijie Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin --- fs/f2fs/data.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 838eae39d3b19..6e39a15a942a9 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1778,9 +1778,10 @@ int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map, int flag) if (map->m_flags & F2FS_MAP_MAPPED) { unsigned int ofs = start_pgofs - map->m_lblk; - f2fs_update_read_extent_cache_range(&dn, - start_pgofs, map->m_pblk + ofs, - map->m_len - ofs); + if (map->m_len > ofs) + f2fs_update_read_extent_cache_range(&dn, + start_pgofs, map->m_pblk + ofs, + map->m_len - ofs); } if (map->m_next_extent) *map->m_next_extent = is_hole ? pgofs + 1 : pgofs; -- 2.51.0