FAILED: patch "[PATCH] ocfs2: strict bound check before memcmp in" failed to apply to 6.6-stable tree

FAILED: patch "[PATCH] ocfs2: strict bound check before memcmp in" failed to apply to 6.6-stable tree

[gregkh]

The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x af77c4fc1871847b528d58b7fdafb4aa1f6a9262
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2024072553-viewing-trapped-d0a4@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:

af77c4fc1871 ("ocfs2: strict bound check before memcmp in ocfs2_xattr_find_entry()")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From af77c4fc1871847b528d58b7fdafb4aa1f6a9262 Mon Sep 17 00:00:00 2001
From: Ferry Meng <mengferry@linux.alibaba.com>
Date: Mon, 20 May 2024 10:40:24 +0800
Subject: [PATCH] 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.

Link: https://lkml.kernel.org/r/20240520024024.1976129-2-joseph.qi@linux.alibaba.com
Signed-off-by: Ferry Meng <mengferry@linux.alibaba.com>
Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reported-by: lei lu <llfamsec@gmail.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mark@fasheh.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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;