Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

fs/ntfs3: validate index entry key bounds

[BUG] A malformed NTFS directory index entry can advertise a key_size larger than the bytes actually present in its NTFS_DE payload. Directory lookup then passes that malformed key to cmp_fnames(), which can read past the end of the kmalloc'ed index buffer.

BUG: KASAN: slab-out-of-bounds in fname_full_size fs/ntfs3/ntfs.h:590 [inline] BUG: KASAN: slab-out-of-bounds in cmp_fnames+0x1ea/0x230 fs/ntfs3/index.c:46 Read of size 1 at addr ffff88801c313018 by task syz.6.3365/9279

Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xbe/0x130 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xd1/0x650 mm/kasan/report.c:482 kasan_report+0xfb/0x140 mm/kasan/report.c:595 __asan_report_load1_noabort+0x14/0x30 mm/kasan/report_generic.c:378 fname_full_size fs/ntfs3/ntfs.h:590 [inline] cmp_fnames+0x1ea/0x230 fs/ntfs3/index.c:46 hdr_find_e.isra.0+0x3ed/0x670 fs/ntfs3/index.c:762 indx_find+0x4b5/0x900 fs/ntfs3/index.c:1186 dir_search_u+0x2c0/0x460 fs/ntfs3/dir.c:254 ntfs_lookup+0x1cc/0x2a0 fs/ntfs3/namei.c:85 __lookup_slow+0x241/0x450 fs/namei.c:1816 lookup_slow fs/namei.c:1833 [inline] walk_component+0x31c/0x570 fs/namei.c:2151 link_path_walk+0x592/0xd60 fs/namei.c:2519 path_lookupat+0x138/0x660 fs/namei.c:2675 filename_lookup+0x1f3/0x560 fs/namei.c:2705 filename_setxattr+0xad/0x1c0 fs/xattr.c:660 pat…