From patchwork Tue Jan 14 12:34:10 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chao Yu X-Patchwork-Id: 13938731 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 4F629E77188 for ; Tue, 14 Jan 2025 12:34:24 +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 1tXg7j-0008P2-IP; Tue, 14 Jan 2025 12:34:23 +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 1tXg7i-0008Os-Lj for linux-f2fs-devel@lists.sourceforge.net; Tue, 14 Jan 2025 12:34:22 +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=AO2csc++QV3v54TEitftSi6kA0P6KKaIXsbd79xIS28=; b=cGeim06h2WJN0hXyVBGmUzRrJ3 g2iBwM/yKTeRwXeKU4vaRm52fAso9EOprbuEprVzms5taLNI25+eHh6D4eIm90JCGNU6z2P0V4ef6 bYVd3DrF/SQui6S3suIGcoh0ohWJapYoaipPGyVoPV+H67AGEiMebCrhiPI53cYAd050=; 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=AO2csc++QV3v54TEitftSi6kA0P6KKaIXsbd79xIS28=; b=O pKmCswKqCsFmYfD6pug7zwmh9wGTt+Ssvxwc1866gWcWAKX9roPAmJGY7o5IZD0fks0IqHQX3HOVo PGrDQSxai1ZNW/EOPUbgZLljFTxKNRsHwU4IzwHbaD/IqcukipSE1q/8X3CD3gVXCyU+5YAs9u+xF AyZxm9Eg56val5l8=; 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 1tXg7h-0001VT-Qv for linux-f2fs-devel@lists.sourceforge.net; Tue, 14 Jan 2025 12:34:22 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id A827E5C5867; Tue, 14 Jan 2025 12:33:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6146CC4CEDD; Tue, 14 Jan 2025 12:34:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1736858056; bh=9k58zGpL3oL/ItwhZdersURYgrd7RDYnth+g55CHYxI=; h=From:To:Cc:Subject:Date:From; b=WezotQfMzgD+Oeuu/8l32awstOUVwH532xW1aVcNPntXQMwzukVSUDVkfZcK6fYrx WVbdUq+HaiG44jomU3cDQZ3s0oVJKgKyzcT53Ks/tXc4tmwxocPBltkH+pVBcZCGu/ MKO70XsG7uop2+6rQECwwCy/3DlXmtHXykD45QhTih3zP8tMKHGZJ/Emt+CKcEfdXw nDGK1QTPW6Kz2QbsD77cij6I4OVqNem5wt1IWchfvrJofDcqz52iVfiobEdJnylL+D PT4tcDOqBtpsPZIGoWCx83wVanO7B7EAVMtOSTGpO4+SkBJiJ4Jf47roJEArzxngHe /46SQ7gBDwxpw== To: jaegeuk@kernel.org Date: Tue, 14 Jan 2025 20:34:10 +0800 Message-ID: <20250114123410.29123-1-chao@kernel.org> X-Mailer: git-send-email 2.48.0.rc2.279.g1de40edade-goog MIME-Version: 1.0 X-Headers-End: 1tXg7h-0001VT-Qv Subject: [f2fs-dev] [PATCH v2] f2fs: fix to do sanity check correctly on i_inline_xattr_size 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: Qasim Ijaz , syzbot+69f5379a1717a0b982a1@syzkaller.appspotmail.com, linux-kernel@vger.kernel.org, syzbot , linux-f2fs-devel@lists.sourceforge.net Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net syzbot reported an out-of-range access issue as below: UBSAN: array-index-out-of-bounds in fs/f2fs/f2fs.h:3292:19 index 18446744073709550491 is out of range for type '__le32[923]' (aka 'unsigned int[923]') CPU: 0 UID: 0 PID: 5338 Comm: syz.0.0 Not tainted 6.12.0-syzkaller-10689-g7af08b57bcb9 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 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 read_inline_xattr+0x273/0x280 lookup_all_xattrs fs/f2fs/xattr.c:341 [inline] f2fs_getxattr+0x57b/0x13b0 fs/f2fs/xattr.c:533 vfs_getxattr_alloc+0x472/0x5c0 fs/xattr.c:393 ima_read_xattr+0x38/0x60 security/integrity/ima/ima_appraise.c:229 process_measurement+0x117a/0x1fb0 security/integrity/ima/ima_main.c:353 ima_file_check+0xd9/0x120 security/integrity/ima/ima_main.c:572 security_file_post_open+0xb9/0x280 security/security.c:3121 do_open fs/namei.c:3830 [inline] path_openat+0x2ccd/0x3590 fs/namei.c:3987 do_file_open_root+0x3a7/0x720 fs/namei.c:4039 file_open_root+0x247/0x2a0 fs/open.c:1382 do_handle_open+0x85b/0x9d0 fs/fhandle.c:414 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 index: 18446744073709550491 (decimal, unsigned long long) = 0xfffffffffffffb9b (hexadecimal) = -1125 (decimal, long long) UBSAN detects that inline_xattr_addr() tries to access .i_addr[-1125]. w/ below testcase, it can reproduce this bug easily: - mkfs.f2fs -f -O extra_attr,flexible_inline_xattr /dev/sdb - mount -o inline_xattr_size=512 /dev/sdb /mnt/f2fs - touch /mnt/f2fs/file - umount /mnt/f2fs - inject.f2fs --node --mb i_inline --nid 4 --val 0x1 /dev/sdb - inject.f2fs --node --mb i_inline_xattr_size --nid 4 --val 2048 /dev/sdb - mount /dev/sdb /mnt/f2fs - getfattr /mnt/f2fs/file The root cause is if metadata of filesystem and inode were fuzzed as below: - extra_attr feature is enabled - flexible_inline_xattr feature is enabled - ri.i_inline_xattr_size = 2048 - F2FS_EXTRA_ATTR bit in ri.i_inline was not set sanity_check_inode() will skip doing sanity check on fi->i_inline_xattr_size, result in using invalid inline_xattr_size later incorrectly, fix it. Meanwhile, let's fix to check lower boundary for .i_inline_xattr_size w/ MIN_INLINE_XATTR_SIZE like we did in parse_options(). There is a related issue reported by syzbot, Qasim Ijaz has anlyzed and fixed it w/ very similar way [1], as discussed, we all agree that it will be better to do sanity check in sanity_check_inode() for fix, so finally, let's fix these two related bugs w/ current patch. Including commit message from Qasim's patch as below, thanks a lot for his contribution. "In f2fs_getxattr(), the function lookup_all_xattrs() allocates a 12-byte (base_size) buffer for an inline extended attribute. However, when __find_inline_xattr() calls __find_xattr(), it uses the macro "list_for_each_xattr(entry, addr)", which starts by calling XATTR_FIRST_ENTRY(addr). This skips a 24-byte struct f2fs_xattr_header at the beginning of the buffer, causing an immediate out-of-bounds read in a 12-byte allocation. The subsequent !IS_XATTR_LAST_ENTRY(entry) check then dereferences memory outside the allocated region, triggering the slab-out-of bounds read. This patch prevents the out-of-bounds read by adding a check to bail out early if inline_size is too small and does not account for the header plus the 4-byte value that IS_XATTR_LAST_ENTRY reads." [1]: https://lore.kernel.org/linux-f2fs-devel/Z32y1rfBY9Qb5ZjM@qasdev.system/ Fixes: 6afc662e68b5 ("f2fs: support flexible inline xattr size") Reported-by: syzbot+69f5379a1717a0b982a1@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-f2fs-devel/674f4e7d.050a0220.17bd51.004f.GAE@google.com Reported-by: syzbot Closes: https://syzkaller.appspot.com/bug?extid=f5e74075e096e757bdbf Tested-by: syzbot Tested-by: Qasim Ijaz Signed-off-by: Chao Yu --- v2: - including commit message from Qasim's patch. fs/f2fs/inode.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c index 282fd320bdb3..7de33da8b3ea 100644 --- a/fs/f2fs/inode.c +++ b/fs/f2fs/inode.c @@ -302,15 +302,6 @@ static bool sanity_check_inode(struct inode *inode, struct page *node_page) F2FS_TOTAL_EXTRA_ATTR_SIZE); return false; } - if (f2fs_sb_has_flexible_inline_xattr(sbi) && - f2fs_has_inline_xattr(inode) && - (!fi->i_inline_xattr_size || - fi->i_inline_xattr_size > MAX_INLINE_XATTR_SIZE)) { - f2fs_warn(sbi, "%s: inode (ino=%lx) has corrupted i_inline_xattr_size: %d, max: %lu", - __func__, inode->i_ino, fi->i_inline_xattr_size, - MAX_INLINE_XATTR_SIZE); - return false; - } if (f2fs_sb_has_compression(sbi) && fi->i_flags & F2FS_COMPR_FL && F2FS_FITS_IN_INODE(ri, fi->i_extra_isize, @@ -320,6 +311,16 @@ static bool sanity_check_inode(struct inode *inode, struct page *node_page) } } + if (f2fs_sb_has_flexible_inline_xattr(sbi) && + f2fs_has_inline_xattr(inode) && + (fi->i_inline_xattr_size < MIN_INLINE_XATTR_SIZE || + fi->i_inline_xattr_size > MAX_INLINE_XATTR_SIZE)) { + f2fs_warn(sbi, "%s: inode (ino=%lx) has corrupted i_inline_xattr_size: %d, min: %lu, max: %lu", + __func__, inode->i_ino, fi->i_inline_xattr_size, + MIN_INLINE_XATTR_SIZE, MAX_INLINE_XATTR_SIZE); + return false; + } + if (!f2fs_sb_has_extra_attr(sbi)) { if (f2fs_sb_has_project_quota(sbi)) { f2fs_warn(sbi, "%s: corrupted inode ino=%lx, wrong feature flag: %u, run fsck to fix.",