From patchwork Wed May 15 13:29:33 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ferry Meng X-Patchwork-Id: 13665280 Received: from out30-124.freemail.mail.aliyun.com (out30-124.freemail.mail.aliyun.com [115.124.30.124]) (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 C579D3B79F for ; Wed, 15 May 2024 13:29:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715779799; cv=none; b=c5a75vtXKbKd4f2Hy8WcyvBo7JFk9rEY5p+FuJAMXxQqh8gTb1HI8cTmKbORJafk2PbluzK38SAEscuk2Nt7GGo2sxRe17WORcyPMaV0I81OYMxzVLoK4bVlcW7dAZtj3cj4gO6eh6RmJT/EYXTydaxCWlk8hKma3zH8glqJ2uA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715779799; c=relaxed/simple; bh=gz0ggfN6+8zfLHC6A1tTQMN9AyVLIKPJ0bhOy7smPrU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=u6fj+yNM7dGuUZeQ54wPIOD+OPAD0f8AnrRn1MNy7HkHucBbwhYO/UJeC2XThat0RIX1A0phmabhDuXC8MRLKyf2p5O8SYrQgB92oj6Z1ofhYzz8EjPG0YKrUE9hz6M/3jreEMhepWNubA5XOoTZfHGLr9HKPMLixX5uv6bhcB0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=j3qSWeB1; arc=none smtp.client-ip=115.124.30.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="j3qSWeB1" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1715779789; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=51HpooU0DkeKvMgR87mxZX64g8YR7tYzfAIqWRzGG0o=; b=j3qSWeB1b7PgB787B5JiLrjNs3fM1W7ImvnYRJu4tgjdUx8vuwhgdmct/HXES6CHibs4ZV2q3RLRYuKM3qOs/fhj623Xj4FTJKPgnILZA52HGt/gWtCcz2GDMFYnrJ7+Q0t1c0aOdTMxTSsuKLPRI6hsAc8zg1GnL5q1gglvJKQ= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R381e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033037067111;MF=mengferry@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0W6YDIFU_1715779785; Received: from j66c13357.sqa.eu95.tbsite.net(mailfrom:mengferry@linux.alibaba.com fp:SMTPD_---0W6YDIFU_1715779785) by smtp.aliyun-inc.com; Wed, 15 May 2024 21:29:48 +0800 From: Ferry Meng To: Mark Fasheh , Joel Becker , Joseph Qi , ocfs2-devel@lists.linux.dev Cc: linux-kernel@vger.kernel.org, Ferry Meng Subject: [PATCH 1/2] ocfs2: add bounds checking to ocfs2_xattr_find_entry() Date: Wed, 15 May 2024 21:29:33 +0800 Message-Id: <20240515132934.69511-2-mengferry@linux.alibaba.com> X-Mailer: git-send-email 2.32.0.3.g01195cf9f In-Reply-To: <20240515132934.69511-1-mengferry@linux.alibaba.com> References: <20240515132934.69511-1-mengferry@linux.alibaba.com> Precedence: bulk X-Mailing-List: ocfs2-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Just add redundant (perhaps paranoia) checks to make sure it doesn't stray beyond valid meory region of ocfs2 xattr entry array during a single match. Maybe this patch can prevent some crash caused by crafted poison images. Signed-off-by: Ferry Meng --- fs/ocfs2/xattr.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c index 3b81213ed7b8..37be4a286faf 100644 --- a/fs/ocfs2/xattr.c +++ b/fs/ocfs2/xattr.c @@ -1062,8 +1062,8 @@ ssize_t ocfs2_listxattr(struct dentry *dentry, return i_ret + b_ret; } -static int ocfs2_xattr_find_entry(int name_index, - const char *name, +static int ocfs2_xattr_find_entry(struct inode *inode, void *end, + int name_index, const char *name, struct ocfs2_xattr_search *xs) { struct ocfs2_xattr_entry *entry; @@ -1076,6 +1076,10 @@ static int ocfs2_xattr_find_entry(int name_index, name_len = strlen(name); entry = xs->here; for (i = 0; i < le16_to_cpu(xs->header->xh_count); i++) { + if ((void *)entry >= end) { + ocfs2_error(inode->i_sb, "corrupted xattr entries"); + return -EFSCORRUPTED; + } cmp = name_index - ocfs2_xattr_get_type(entry); if (!cmp) cmp = name_len - entry->xe_name_len; @@ -1166,7 +1170,7 @@ static int ocfs2_xattr_ibody_get(struct inode *inode, xs->base = (void *)xs->header; xs->here = xs->header->xh_entries; - ret = ocfs2_xattr_find_entry(name_index, name, xs); + ret = ocfs2_xattr_find_entry(inode, xs->end, name_index, name, xs); if (ret) return ret; size = le64_to_cpu(xs->here->xe_value_size); @@ -2698,7 +2702,7 @@ static int ocfs2_xattr_ibody_find(struct inode *inode, /* Find the named attribute. */ if (oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL) { - ret = ocfs2_xattr_find_entry(name_index, name, xs); + ret = ocfs2_xattr_find_entry(inode, xs->end, name_index, name, xs); if (ret && ret != -ENODATA) return ret; xs->not_found = ret; @@ -2833,7 +2837,7 @@ static int ocfs2_xattr_block_find(struct inode *inode, xs->end = (void *)(blk_bh->b_data) + blk_bh->b_size; xs->here = xs->header->xh_entries; - ret = ocfs2_xattr_find_entry(name_index, name, xs); + ret = ocfs2_xattr_find_entry(inode, xs->end, name_index, name, xs); } else ret = ocfs2_xattr_index_block_find(inode, blk_bh, name_index,