This is a note to let you know that I've just added the patch titled
ocfs2: add bounds checking to ocfs2_xattr_find_entry()
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ocfs2-add-bounds-checking-to-ocfs2_xattr_find_entry.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit ec099dd5027d22c1c5286343756db11fdef46abd
Author: Ferry Meng <mengferry@xxxxxxxxxxxxxxxxx>
Date: Mon May 20 10:40:23 2024 +0800
ocfs2: add bounds checking to ocfs2_xattr_find_entry()
[ Upstream commit 9e3041fecdc8f78a5900c3aa51d3d756e73264d6 ]
Add a paranoia check to make sure it doesn't stray beyond valid memory
region containing ocfs2 xattr entries when scanning for a match. It will
prevent out-of-bound access in case of crafted images.
Link: https://lkml.kernel.org/r/20240520024024.1976129-1-joseph.qi@xxxxxxxxxxxxxxxxx
Signed-off-by: Ferry Meng <mengferry@xxxxxxxxxxxxxxxxx>
Signed-off-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx>
Reported-by: lei lu <llfamsec@xxxxxxxxx>
Reviewed-by: Joseph Qi <joseph.qi@xxxxxxxxxxxxxxxxx>
Cc: Mark Fasheh <mark@xxxxxxxxxx>
Cc: Joel Becker <jlbec@xxxxxxxxxxxx>
Cc: Junxiao Bi <junxiao.bi@xxxxxxxxxx>
Cc: Changwei Ge <gechangwei@xxxxxxx>
Cc: Gang He <ghe@xxxxxxxx>
Cc: Jun Piao <piaojun@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Stable-dep-of: af77c4fc1871 ("ocfs2: strict bound check before memcmp in ocfs2_xattr_find_entry()")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
index 54d881c9ac81e..8ec85c2503f23 100644
--- a/fs/ocfs2/xattr.c
+++ b/fs/ocfs2/xattr.c
@@ -1076,7 +1076,7 @@ ssize_t ocfs2_listxattr(struct dentry *dentry,
return i_ret + b_ret;
}
-static int ocfs2_xattr_find_entry(int name_index,
+static int ocfs2_xattr_find_entry(struct inode *inode, int name_index,
const char *name,
struct ocfs2_xattr_search *xs)
{
@@ -1090,6 +1090,10 @@ 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 >= xs->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;
@@ -1180,7 +1184,7 @@ 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, name_index, name, xs);
if (ret)
return ret;
size = le64_to_cpu(xs->here->xe_value_size);
@@ -2712,7 +2716,7 @@ 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, name_index, name, xs);
if (ret && ret != -ENODATA)
return ret;
xs->not_found = ret;
@@ -2847,7 +2851,7 @@ 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, name_index, name, xs);
} else
ret = ocfs2_xattr_index_block_find(inode, blk_bh,
name_index,
