The patch titled
Subject: ocfs2: strict bound check before memcmp in ocfs2_xattr_find_entry()
has been added to the -mm mm-nonmm-unstable branch. Its filename is
ocfs2-strict-bound-check-before-memcmp-in-ocfs2_xattr_find_entry.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/ocfs2-strict-bound-check-before-memcmp-in-ocfs2_xattr_find_entry.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Ferry Meng <mengferry@xxxxxxxxxxxxxxxxx>
Subject: ocfs2: strict bound check before memcmp in ocfs2_xattr_find_entry()
Date: Mon, 20 May 2024 10:40:24 +0800
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@xxxxxxxxxxxxxxxxx
Signed-off-by: Ferry Meng <mengferry@xxxxxxxxxxxxxxxxx>
Signed-off-by-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx>
Reported-by: lei lu <llfamsec@xxxxxxxxx>
Reviewed-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx>
Cc: Changwei Ge <gechangwei@xxxxxxx>
Cc: Gang He <ghe@xxxxxxxx>
Cc: Joel Becker <jlbec@xxxxxxxxxxxx>
Cc: Jun Piao <piaojun@xxxxxxxxxx>
Cc: Junxiao Bi <junxiao.bi@xxxxxxxxxx>
Cc: Mark Fasheh <mark@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/ocfs2/xattr.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)
--- a/fs/ocfs2/xattr.c~ocfs2-strict-bound-check-before-memcmp-in-ocfs2_xattr_find_entry
+++ a/fs/ocfs2/xattr.c
@@ -1068,7 +1068,7 @@ static int ocfs2_xattr_find_entry(struct
{
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
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;
_
Patches currently in -mm which might be from mengferry@xxxxxxxxxxxxxxxxx are
ocfs2-add-bounds-checking-to-ocfs2_xattr_find_entry.patch
ocfs2-strict-bound-check-before-memcmp-in-ocfs2_xattr_find_entry.patch
