syzbot
KASAN: slab-out-of-bounds Write in wp384_final
Status: fixed on 2018/07/09 18:05
Subsystems:
crypto
[Documentation on labels]
Fix commit:
3619dec5103d
dh key: fix rounding up KDF output length
First crash: 2967d, last: 2948d
Sample crash report:
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:345 [inline]
BUG: KASAN: slab-out-of-bounds in wp384_final+0x93/0xe0 crypto/wp512.c:1105
Write of size 48 at addr ffff8801b70856b0 by task syz-executor188/4473
CPU: 1 PID: 4473 Comm: syz-executor188 Not tainted 4.17.0+ #92
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1b9/0x294 lib/dump_stack.c:113
print_address_description+0x6c/0x20b mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:354 [inline]
kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
check_memory_region_inline mm/kasan/kasan.c:260 [inline]
check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
memcpy+0x37/0x50 mm/kasan/kasan.c:303
memcpy include/linux/string.h:345 [inline]
wp384_final+0x93/0xe0 crypto/wp512.c:1105
crypto_shash_final+0x104/0x260 crypto/shash.c:152
kdf_ctr security/keys/dh.c:186 [inline]
keyctl_dh_compute_kdf security/keys/dh.c:217 [inline]
__keyctl_dh_compute+0x1184/0x1bc0 security/keys/dh.c:389
keyctl_dh_compute+0xb9/0x100 security/keys/dh.c:425
__do_sys_keyctl security/keys/keyctl.c:1741 [inline]
__se_sys_keyctl security/keys/keyctl.c:1637 [inline]
__x64_sys_keyctl+0x12a/0x3b0 security/keys/keyctl.c:1637
do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440019
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 6b 45 00 00 c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffd31e8d908 EFLAGS: 00000217 ORIG_RAX: 00000000000000fa
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440019
RDX: 0000000020000300 RSI: 0000000020000040 RDI: 0000000000000017
RBP: 00000000006ca018 R08: 0000000020c61fc8 R09: 00000000004002c8
R10: 00000000000000fb R11: 0000000000000217 R12: 0000000000401940
R13: 00000000004019d0 R14: 0000000000000000 R15: 0000000000000000
Allocated by task 4473:
save_stack+0x43/0xd0 mm/kasan/kasan.c:448
set_track mm/kasan/kasan.c:460 [inline]
kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
__do_kmalloc mm/slab.c:3718 [inline]
__kmalloc+0x14e/0x760 mm/slab.c:3727
kmalloc include/linux/slab.h:518 [inline]
keyctl_dh_compute_kdf security/keys/dh.c:211 [inline]
__keyctl_dh_compute+0xfe9/0x1bc0 security/keys/dh.c:389
keyctl_dh_compute+0xb9/0x100 security/keys/dh.c:425
__do_sys_keyctl security/keys/keyctl.c:1741 [inline]
__se_sys_keyctl security/keys/keyctl.c:1637 [inline]
__x64_sys_keyctl+0x12a/0x3b0 security/keys/keyctl.c:1637
do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Freed by task 0:
(stack is not available)
The buggy address belongs to the object at ffff8801b70855c0
which belongs to the cache kmalloc-256 of size 256
The buggy address is located 240 bytes inside of
256-byte region [ffff8801b70855c0, ffff8801b70856c0)
The buggy address belongs to the page:
page:ffffea0006dc2140 count:1 mapcount:0 mapping:ffff8801da8007c0 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffffea0006bb01c8 ffff8801da801648 ffff8801da8007c0
raw: 0000000000000000 ffff8801b70850c0 000000010000000c 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8801b7085580: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
ffff8801b7085600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801b7085680: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
^
ffff8801b7085700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8801b7085780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
* Struck through repros no longer work on HEAD.