syzbot


KASAN: slab-out-of-bounds Write in rmd320_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: 2137d, last: 2117d

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 rmd320_final+0x201/0x240 crypto/rmd320.c:358
Write of size 4 at addr ffff8801babaa0b0 by task syz-executor890/4483

CPU: 0 PID: 4483 Comm: syz-executor890 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
 __asan_report_store4_noabort+0x17/0x20 mm/kasan/report.c:437
 rmd320_final+0x201/0x240 crypto/rmd320.c:358
 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: 0033:0x440009
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:00007fff72f71088 EFLAGS: 00000217 ORIG_RAX: 00000000000000fa
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440009
RDX: 0000000020000780 RSI: 0000000020000740 RDI: 0000000000000017
RBP: 00000000006ca018 R08: 0000000020000880 R09: 00000000004002c8
R10: 000000000000002d R11: 0000000000000217 R12: 0000000000401930
R13: 00000000004019c0 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 4483:
 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 ffff8801babaa080
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 48 bytes inside of
 64-byte region [ffff8801babaa080, ffff8801babaa0c0)
The buggy address belongs to the page:
page:ffffea0006eaea80 count:1 mapcount:0 mapping:ffff8801da800340 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffffea00073deac8 ffff8801da801348 ffff8801da800340
raw: 0000000000000000 ffff8801babaa000 0000000100000020 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801baba9f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801babaa000: 00 00 00 00 00 00 03 fc fc fc fc fc fc fc fc fc
>ffff8801babaa080: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
                                     ^
 ffff8801babaa100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801babaa180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (44):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/06/09 11:08 upstream 7d3bf613e99a 866118af .config console log report syz C ci-upstream-kasan-gce-root
2018/06/09 09:06 upstream 410feb75de24 866118af .config console log report syz C ci-upstream-kasan-gce-root
2018/06/07 23:47 upstream 1c8c5a9d38f6 645e75f8 .config console log report syz C ci-upstream-kasan-gce
2018/06/08 04:36 upstream 68abbe729567 645e75f8 .config console log report syz C ci-upstream-kasan-gce-386
2018/06/08 02:40 upstream 1c8c5a9d38f6 645e75f8 .config console log report syz ci-upstream-kasan-gce-386
2018/06/27 16:12 upstream 813835028e9a 43e60f7e .config console log report ci-upstream-kasan-gce
2018/06/26 23:56 upstream 813835028e9a b0294c53 .config console log report ci-upstream-kasan-gce
2018/06/25 17:57 upstream 6f0d349d922b 2064fc5c .config console log report ci-upstream-kasan-gce
2018/06/25 15:31 upstream 6f0d349d922b 2064fc5c .config console log report ci-upstream-kasan-gce
2018/06/25 04:43 upstream 7daf201d7fe8 2064fc5c .config console log report ci-upstream-kasan-gce
2018/06/24 08:54 upstream 77072ca59fdd 2064fc5c .config console log report ci-upstream-kasan-gce-root
2018/06/22 07:26 upstream 27db64f65f1b 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/21 23:22 upstream 27db64f65f1b 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/21 19:39 upstream 1abd8a8f39cd 095ef806 .config console log report ci-upstream-kasan-gce-root
2018/06/21 18:09 upstream 1abd8a8f39cd 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/21 15:03 upstream 1abd8a8f39cd 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/20 14:11 upstream 81e97f01371f 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/19 19:12 upstream ba4dbdedd3ed 732e4256 .config console log report ci-upstream-kasan-gce-root
2018/06/19 14:37 upstream ba4dbdedd3ed 732e4256 .config console log report ci-upstream-kasan-gce-root
2018/06/17 15:32 upstream ce397d215ccd 27c5f59f .config console log report ci-upstream-kasan-gce-root
2018/06/17 11:42 upstream ce397d215ccd 27c5f59f .config console log report ci-upstream-kasan-gce
2018/06/17 01:54 upstream 35773c93817c 27c5f59f .config console log report ci-upstream-kasan-gce
2018/06/17 00:45 upstream 35773c93817c 27c5f59f .config console log report ci-upstream-kasan-gce-root
2018/06/16 19:12 upstream 35773c93817c 27c5f59f .config console log report ci-upstream-kasan-gce-root
2018/06/16 13:22 upstream 9215310cf13b 27c5f59f .config console log report ci-upstream-kasan-gce
2018/06/16 06:36 upstream 9215310cf13b 27c5f59f .config console log report ci-upstream-kasan-gce
2018/06/14 23:41 upstream 2837461dbe6f 27c5f59f .config console log report ci-upstream-kasan-gce
2018/06/14 15:21 upstream 2837461dbe6f 27c5f59f .config console log report ci-upstream-kasan-gce
2018/06/10 16:52 upstream 3ca24ce9ff76 866118af .config console log report ci-upstream-kasan-gce
2018/06/10 10:21 upstream a16afaf7928b 866118af .config console log report ci-upstream-kasan-gce
2018/06/10 09:24 upstream a16afaf7928b 866118af .config console log report ci-upstream-kasan-gce
2018/06/10 05:12 upstream a16afaf7928b 866118af .config console log report ci-upstream-kasan-gce
2018/06/07 22:05 upstream 1c8c5a9d38f6 645e75f8 .config console log report ci-upstream-kasan-gce
2018/06/27 15:11 upstream 813835028e9a 43e60f7e .config console log report ci-upstream-kasan-gce-386
2018/06/24 17:35 upstream 7daf201d7fe8 2064fc5c .config console log report ci-upstream-kasan-gce-386
2018/06/21 08:51 upstream 1abd8a8f39cd 095ef806 .config console log report ci-upstream-kasan-gce-386
2018/06/20 20:21 upstream 81e97f01371f 095ef806 .config console log report ci-upstream-kasan-gce-386
2018/06/20 15:52 upstream 81e97f01371f 095ef806 .config console log report ci-upstream-kasan-gce-386
2018/06/20 07:33 upstream ba4dbdedd3ed 095ef806 .config console log report ci-upstream-kasan-gce-386
2018/06/18 15:28 upstream 9ffc59d57228 27c5f59f .config console log report ci-upstream-kasan-gce-386
2018/06/17 15:15 upstream ce397d215ccd 27c5f59f .config console log report ci-upstream-kasan-gce-386
2018/06/16 22:42 upstream 35773c93817c 27c5f59f .config console log report ci-upstream-kasan-gce-386
2018/06/16 15:37 upstream 9215310cf13b 27c5f59f .config console log report ci-upstream-kasan-gce-386
2018/06/13 17:17 upstream f5b7769eb040 27c5f59f .config console log report ci-upstream-kasan-gce-386
* Struck through repros no longer work on HEAD.