lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20240517094147.87133-3-mengferry@linux.alibaba.com>
Date: Fri, 17 May 2024 17:41:47 +0800
From: Ferry Meng <mengferry@...ux.alibaba.com>
To: Mark Fasheh <mark@...heh.com>,
	Joel Becker <jlbec@...lplan.org>,
	Joseph Qi <joseph.qi@...ux.alibaba.com>,
	ocfs2-devel@...ts.linux.dev
Cc: linux-kernel@...r.kernel.org,
	Ferry Meng <mengferry@...ux.alibaba.com>
Subject: [PATCH v2 2/2] ocfs2: strict bound check before memcmp in ocfs2_xattr_find_entry()

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 <mengferry@...ux.alibaba.com>
---
 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;
-- 
2.32.0.3.g01195cf9f


Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ