From patchwork Mon Mar 3 03:47:38 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chao Yu X-Patchwork-Id: 13998144 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0A14EC282C5 for ; Mon, 3 Mar 2025 03:48:22 +0000 (UTC) Received: from [127.0.0.1] (helo=sfs-ml-4.v29.lw.sourceforge.com) by sfs-ml-4.v29.lw.sourceforge.com with esmtp (Exim 4.95) (envelope-from ) id 1town0-0003tP-LY; Mon, 03 Mar 2025 03:48:22 +0000 Received: from [172.30.29.66] (helo=mx.sourceforge.net) by sfs-ml-4.v29.lw.sourceforge.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1towmz-0003tJ-1Z for linux-f2fs-devel@lists.sourceforge.net; Mon, 03 Mar 2025 03:48:21 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=Content-Transfer-Encoding:MIME-Version:Message-ID: Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=BJYeIxMf19+z4QmtDjyjOtuHyK4wkeAkOZF1rD0/VEg=; b=benr2V73qk/g8AZYNG3EJj3mN6 ANQbt2D8QYmIqz8cc3hoI1wpwjhm6irXx+xuldGeM0Vo5I9jOg1KWGhKP3y8HGDvji+WKGWIjUNJM 54IztL74WQd7ORFWSedazG85tWbN8lmgF729P7DMyR75BsPzt2Jt+dkIStpuRkkvPhgM=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=Content-Transfer-Encoding:MIME-Version:Message-ID:Date:Subject:Cc:To:From :Sender:Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: References:List-Id:List-Help:List-Unsubscribe:List-Subscribe:List-Post: List-Owner:List-Archive; bh=BJYeIxMf19+z4QmtDjyjOtuHyK4wkeAkOZF1rD0/VEg=; b=B J6lEqniYBeA2Y29vF4ksi+gX8wIXHzOD2MxI2Fks9YaC9DNdFKwlgcB9k2SchdX+z2XHxZ5MqvSpP AVIKIpO4R0khy8Gi8Mjyh7wMiKWtSvlZrkOqUYmOZGIXC8jxm498csC28ZIMawXmQzZZHqNOBZmUg vBULJ4BDtVu5VsaA=; Received: from dfw.source.kernel.org ([139.178.84.217]) by sfi-mx-2.v28.lw.sourceforge.com with esmtps (TLS1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.95) id 1towmt-0006rZ-Ci for linux-f2fs-devel@lists.sourceforge.net; Mon, 03 Mar 2025 03:48:20 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 35E675C5559; Mon, 3 Mar 2025 03:45:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 545F5C4CED6; Mon, 3 Mar 2025 03:48:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1740973689; bh=Q4EsHzFu7W+a0NYcnNSUCxAn6bGe2wN70WdlrxfrVUk=; h=From:To:Cc:Subject:Date:From; b=uv3lF58dTmuX5e0dfQvHx3MjxyVxEWNiO0mbh11YhXyyw7Pn5loIPHJrk50qmtCPM RE/TdAIYDGNz9n4sEYW2snlHhymS7CPyqM4Ky2t0VQxyrS8CWVQBaGC+zy9U0EhArQ Op6lH02C9KTd+C4lWO0fufZbe/2TMaiWWr4IBUIXrws74vmS3En1nS3C4P/iYzMNYt XSBTlFdAkYKX1r8nraTX1JZxghwcqOvefV5EDsTVDOlMsVizURsxBTjh7pPPkMvaTm fjvM2NSBj6HHozBycTgGOjk+VgBNbVNGpUAaFonEpaGMOVsUFrStrpYYFg3jiTEtD+ ZckyXj3Vw5xAA== To: jaegeuk@kernel.org Date: Mon, 3 Mar 2025 11:47:38 +0800 Message-ID: <20250303034738.1355927-1-chao@kernel.org> X-Mailer: git-send-email 2.48.1.711.g2feabab25a-goog MIME-Version: 1.0 X-Headers-End: 1towmt-0006rZ-Ci Subject: [f2fs-dev] [PATCH] f2fs: fix to avoid out-of-bounds access in f2fs_truncate_inode_blocks() X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Chao Yu via Linux-f2fs-devel From: Chao Yu Reply-To: Chao Yu Cc: syzbot+6653f10281a1badc749e@syzkaller.appspotmail.com, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net syzbot reports an UBSAN issue as below: ------------[ cut here ]------------ UBSAN: array-index-out-of-bounds in fs/f2fs/node.h:381:10 index 18446744073709550692 is out of range for type '__le32[5]' (aka 'unsigned int[5]') CPU: 0 UID: 0 PID: 5318 Comm: syz.0.0 Not tainted 6.14.0-rc3-syzkaller-00060-g6537cfb395f3 #0 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 ubsan_epilogue lib/ubsan.c:231 [inline] __ubsan_handle_out_of_bounds+0x121/0x150 lib/ubsan.c:429 get_nid fs/f2fs/node.h:381 [inline] f2fs_truncate_inode_blocks+0xa5e/0xf60 fs/f2fs/node.c:1181 f2fs_do_truncate_blocks+0x782/0x1030 fs/f2fs/file.c:808 f2fs_truncate_blocks+0x10d/0x300 fs/f2fs/file.c:836 f2fs_truncate+0x417/0x720 fs/f2fs/file.c:886 f2fs_file_write_iter+0x1bdb/0x2550 fs/f2fs/file.c:5093 aio_write+0x56b/0x7c0 fs/aio.c:1633 io_submit_one+0x8a7/0x18a0 fs/aio.c:2052 __do_sys_io_submit fs/aio.c:2111 [inline] __se_sys_io_submit+0x171/0x2e0 fs/aio.c:2081 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f238798cde9 index 18446744073709550692 (decimal, unsigned long long) = 0xfffffffffffffc64 (hexadecimal, unsigned long long) = -924 (decimal, long long) In f2fs_truncate_inode_blocks(), UBSAN detects that get_nid() tries to access .i_nid[-924], it means both offset[0] and level should zero. The possible case should be in f2fs_do_truncate_blocks(), we try to truncate inode size to zero, however, dn.ofs_in_node is zero and dn.node_page is not an inode page, so it fails to truncate inode page, and then pass zeroed free_from to f2fs_truncate_inode_blocks(), result in this issue. if (dn.ofs_in_node || IS_INODE(dn.node_page)) { f2fs_truncate_data_blocks_range(&dn, count); free_from += count; } I guess the reason why dn.node_page is not an inode page could be: there are multiple nat entries share the same node block address, once the node block address was reused, f2fs_get_node_page() may load a non-inode block. Let's add a sanity check for such condition to avoid out-of-bounds access issue. Reported-by: syzbot+6653f10281a1badc749e@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/66fdcdf3.050a0220.40bef.0025.GAE@google.com Signed-off-by: Chao Yu --- fs/f2fs/node.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index e1ed7ccfb690..36614a1c2590 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -1135,7 +1135,14 @@ int f2fs_truncate_inode_blocks(struct inode *inode, pgoff_t from) trace_f2fs_truncate_inode_blocks_enter(inode, from); level = get_node_path(inode, from, offset, noffset); - if (level < 0) { + if (level <= 0) { + if (!level) { + level = -EFSCORRUPTED; + f2fs_err(sbi, "%s: inode ino=%lx has corrupted node block, from:%lu addrs:%u", + __func__, inode->i_ino, + from, ADDRS_PER_INODE(inode)); + set_sbi_flag(sbi, SBI_NEED_FSCK); + } trace_f2fs_truncate_inode_blocks_exit(inode, level); return level; }