From patchwork Fri May 17 09:41:47 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ferry Meng X-Patchwork-Id: 13666805 Received: from out30-132.freemail.mail.aliyun.com (out30-132.freemail.mail.aliyun.com [115.124.30.132]) (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 15AAB22EF8 for ; Fri, 17 May 2024 09:42:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.132 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715938934; cv=none; b=WjUkXM9zD24d2ORvOrc70nECkmLLQbWHHHklB1mfTBJCnj7DOEdU8DCvC2xl1z8ukT2B02ATe4CG7oN35FLdp90w/enVzQHe9wBPa0MpG8m+sdKGA251E2wXILZTblBng9hr1K82cVACWR/0MepqNbdS10d8hAOn25JVIoDSwbQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715938934; c=relaxed/simple; bh=g2mtvEDKT6K/qKPF1XuOt7jvGo9xLXUL9uFTaUoQL74=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=sQx4fCP3NfGctwpadsDLJn/KT4JdWts1q2wn8j4JYE1eVOGc7j3VpZ6MfYJu45NoJ3JHqkCvgV4ixNZm8elfaUR1yT7lnClKKCSgKfAAZOAfzfVEvdCAumtVqrKezRiniddKzXfrCu04iAIahQhEank2Fa7mANs2zC3axeY1qpw= 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=SqHlweC7; arc=none smtp.client-ip=115.124.30.132 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="SqHlweC7" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1715938929; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=jOPrgQph3RGN8jKqsS+ujDSxSagogaAaFxEI3R+UkrM=; b=SqHlweC73EQI6reHhTzOzg/IKidEybGlLgUYltFK3K3tZJdp5OwfFVmwBCaOfZvGyTqbOTa2bnjZCKr6NsvCQp0ptpwVObyB6iiQTsUBfugsGFhJ3O4ir7X8OR8FfYTBHHPlxW6G9wpnVDetnWSza20w+FHiZhDZLiWwW9fVnak= X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R121e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033068173054;MF=mengferry@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0W6eF4Lh_1715938925; Received: from j66c13357.sqa.eu95.tbsite.net(mailfrom:mengferry@linux.alibaba.com fp:SMTPD_---0W6eF4Lh_1715938925) by smtp.aliyun-inc.com; Fri, 17 May 2024 17:42:07 +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 v2 2/2] ocfs2: strict bound check before memcmp in ocfs2_xattr_find_entry() Date: Fri, 17 May 2024 17:41:47 +0800 Message-Id: <20240517094147.87133-3-mengferry@linux.alibaba.com> X-Mailer: git-send-email 2.32.0.3.g01195cf9f In-Reply-To: <20240517094147.87133-1-mengferry@linux.alibaba.com> References: <20240517094147.87133-1-mengferry@linux.alibaba.com> Precedence: bulk X-Mailing-List: ocfs2-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 xattr in ocfs2 maybe 'non-indexed', which saved with additional space requested. It's better to check if the memory is out of bound before memcmp, although this possibility mainly comes from crafted poisonous images. Signed-off-by: Ferry Meng Reported-by: lei lu Reviewed-by: Joseph Qi --- fs/ocfs2/xattr.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c index 8aea94c90739..35c0cc2a51af 100644 --- a/fs/ocfs2/xattr.c +++ b/fs/ocfs2/xattr.c @@ -1068,7 +1068,7 @@ static int ocfs2_xattr_find_entry(struct inode *inode, int name_index, { struct ocfs2_xattr_entry *entry; size_t name_len; - int i, cmp = 1; + int i, name_offset, cmp = 1; if (name == NULL) return -EINVAL; @@ -1083,10 +1083,15 @@ static int ocfs2_xattr_find_entry(struct inode *inode, int name_index, cmp = name_index - ocfs2_xattr_get_type(entry); if (!cmp) cmp = name_len - entry->xe_name_len; - if (!cmp) - cmp = memcmp(name, (xs->base + - le16_to_cpu(entry->xe_name_offset)), - name_len); + if (!cmp) { + name_offset = le16_to_cpu(entry->xe_name_offset); + if ((xs->base + name_offset + name_len) > xs->end) { + ocfs2_error(inode->i_sb, + "corrupted xattr entries"); + return -EFSCORRUPTED; + } + cmp = memcmp(name, (xs->base + name_offset), name_len); + } if (cmp == 0) break; entry += 1;