5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Zeng Heng <zengheng4@xxxxxxxxxx>
commit 8e7e27b2ee1e19c4040d4987e345f678a74c0aed upstream.
Here is a BUG report about linux-6.1 from syzbot, but it still remains
within upstream:
BUG: KASAN: slab-out-of-bounds in ntfs_list_ea fs/ntfs3/xattr.c:191 [inline]
BUG: KASAN: slab-out-of-bounds in ntfs_listxattr+0x401/0x570 fs/ntfs3/xattr.c:710
Read of size 1 at addr ffff888021acaf3d by task syz-executor128/3632
Call Trace:
kasan_report+0x139/0x170 mm/kasan/report.c:495
ntfs_list_ea fs/ntfs3/xattr.c:191 [inline]
ntfs_listxattr+0x401/0x570 fs/ntfs3/xattr.c:710
vfs_listxattr fs/xattr.c:457 [inline]
listxattr+0x293/0x2d0 fs/xattr.c:804
path_listxattr fs/xattr.c:828 [inline]
__do_sys_llistxattr fs/xattr.c:846 [inline]
Before derefering field members of `ea` in unpacked_ea_size(), we need to
check whether the EA_FULL struct is located in access validate range.
Similarly, when derefering `ea->name` field member, we need to check
whethe the ea->name is located in access validate range, too.
Fixes: be71b5cba2e6 ("fs/ntfs3: Add attrib operations")
Reported-by: syzbot+9fcea5ef6dc4dc72d334@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Zeng Heng <zengheng4@xxxxxxxxxx>
[almaz.alexandrovich@xxxxxxxxxxxxxxxxxxxx: took the ret variable out of the loop block]
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ntfs3/xattr.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/fs/ntfs3/xattr.c
+++ b/fs/ntfs3/xattr.c
@@ -209,7 +209,8 @@ static ssize_t ntfs_list_ea(struct ntfs_
size = le32_to_cpu(info->size);
/* Enumerate all xattrs. */
- for (ret = 0, off = 0; off < size; off += ea_size) {
+ ret = 0;
+ for (off = 0; off + sizeof(struct EA_FULL) < size; off += ea_size) {
ea = Add2Ptr(ea_all, off);
ea_size = unpacked_ea_size(ea);
@@ -217,6 +218,10 @@ static ssize_t ntfs_list_ea(struct ntfs_
break;
if (buffer) {
+ /* Check if we can use field ea->name */
+ if (off + ea_size > size)
+ break;
+
if (ret + ea->name_len + 1 > bytes_per_buffer) {
err = -ERANGE;
goto out;
