fs/ntfs3: fix panic about slab-out-of-bounds caused by ntfs_list_ea()
authorZeng Heng <zengheng4@huawei.com>
Thu, 20 Apr 2023 07:46:22 +0000 (15:46 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 25 Oct 2023 10:03:05 +0000 (12:03 +0200)
commitc1f2638e315bac360e41277f3d2bc1017a542ef1
tree0e1026ba6995ee4f7c6401472f71aa2ff470d3b1
parentfb80a28fef2b8be5854c5e8961d0d166c7960c9a
fs/ntfs3: fix panic about slab-out-of-bounds caused by ntfs_list_ea()

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@syzkaller.appspotmail.com
Signed-off-by: Zeng Heng <zengheng4@huawei.com>
[almaz.alexandrovich@paragon-software.com: took the ret variable out of the loop block]
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fs/ntfs3/xattr.c