syzbot


KASAN: slab-out-of-bounds Write in sha1_finup

Status: fixed on 2018/07/09 18:05
Subsystems: crypto
[Documentation on labels]
Reported-by: syzbot+486f97f892efeb2075a3@syzkaller.appspotmail.com
Fix commit: 3619dec5103d dh key: fix rounding up KDF output length
First crash: 2142d, last: 2122d
Duplicate bugs (3)
duplicates (3):
Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
KASAN: slab-out-of-bounds Write in rmd160_final crypto C 82 2122d 2142d 22/26 closed as dup on 2018/06/07 19:18
KASAN: slab-out-of-bounds Write in sha256_final crypto C 163 2122d 2142d 22/26 closed as dup on 2018/06/07 19:17
KASAN: slab-out-of-bounds Write in sha256_finup crypto C 180 2122d 2142d 22/26 closed as dup on 2018/06/07 19:17
Discussions (3)
Title Replies (including bot) Last reply
[PATCH 0/3] KEYS: Miscellaneous fixes 5 (5) 2018/06/26 16:39
[PATCH] dh key: fix rounding up KDF output length 7 (7) 2018/06/25 17:14
KASAN: slab-out-of-bounds Write in sha1_finup 0 (2) 2018/06/07 14:43

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 put_unaligned_be32 include/linux/unaligned/access_ok.h:60 [inline]
BUG: KASAN: slab-out-of-bounds in sha1_base_finish include/crypto/sha1_base.h:102 [inline]
BUG: KASAN: slab-out-of-bounds in sha1_finup+0x44e/0x4b0 arch/x86/crypto/sha1_ssse3_glue.c:70
Write of size 4 at addr ffff8801d71f3958 by task syz-executor474/4581

CPU: 0 PID: 4581 Comm: syz-executor474 Not tainted 4.17.0+ #89
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
 put_unaligned_be32 include/linux/unaligned/access_ok.h:60 [inline]
 sha1_base_finish include/crypto/sha1_base.h:102 [inline]
 sha1_finup+0x44e/0x4b0 arch/x86/crypto/sha1_ssse3_glue.c:70
 sha1_avx2_finup arch/x86/crypto/sha1_ssse3_glue.c:232 [inline]
 sha1_avx2_final+0x28/0x30 arch/x86/crypto/sha1_ssse3_glue.c:238
 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: 0033:0x43ffa9
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:00007fffd75787b8 EFLAGS: 00000217 ORIG_RAX: 00000000000000fa
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ffa9
RDX: 0000000020a53ffb RSI: 0000000020000100 RDI: 0000000000000017
RBP: 00000000006ca018 R08: 0000000020c61fc8 R09: 00000000004002c8
R10: 0000000000000005 R11: 0000000000000217 R12: 00000000004018d0
R13: 0000000000401960 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 4581:
 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 2886:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xd9/0x260 mm/slab.c:3813
 single_release+0x8f/0xb0 fs/seq_file.c:609
 __fput+0x353/0x890 fs/file_table.c:209
 ____fput+0x15/0x20 fs/file_table.c:243
 task_work_run+0x1e4/0x290 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:192 [inline]
 exit_to_usermode_loop+0x2bd/0x310 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:265 [inline]
 do_syscall_64+0x6ac/0x800 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801d71f3940
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 24 bytes inside of
 32-byte region [ffff8801d71f3940, ffff8801d71f3960)
The buggy address belongs to the page:
page:ffffea00075c7cc0 count:1 mapcount:0 mapping:ffff8801d71f3000 index:0xffff8801d71f3fc1
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801d71f3000 ffff8801d71f3fc1 000000010000003d
raw: ffffea0007606f20 ffffea00075c7be0 ffff8801da8001c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d71f3800: 00 00 00 00 fc fc fc fc 00 fc fc fc fc fc fc fc
 ffff8801d71f3880: 00 00 00 00 fc fc fc fc 00 fc fc fc fc fc fc fc
>ffff8801d71f3900: fb fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc
                                                    ^
 ffff8801d71f3980: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
 ffff8801d71f3a00: fb fb fb fb fc fc fc fc 00 00 00 fc fc fc fc fc
==================================================================

Crashes (119):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/06/07 19:41 upstream 1c8c5a9d38f6 645e75f8 .config console log report syz C ci-upstream-kasan-gce-root
2018/06/07 18:37 upstream 1c8c5a9d38f6 645e75f8 .config console log report syz C ci-upstream-kasan-gce-root
2018/06/07 15:52 upstream 1c8c5a9d38f6 645e75f8 .config console log report syz C ci-upstream-kasan-gce
2018/06/07 14:42 upstream 1c8c5a9d38f6 645e75f8 .config console log report syz C ci-upstream-kasan-gce
2018/06/07 14:49 upstream 1c8c5a9d38f6 645e75f8 .config console log report syz ci-upstream-kasan-gce-386
2018/06/07 11:08 upstream 1c8c5a9d38f6 d2ba33fa .config console log report syz ci-upstream-kasan-gce-386
2018/06/27 14:51 upstream 813835028e9a 43e60f7e .config console log report ci-upstream-kasan-gce-root
2018/06/27 10:52 upstream 813835028e9a 43e60f7e .config console log report ci-upstream-kasan-gce
2018/06/27 01:10 upstream 813835028e9a b0294c53 .config console log report ci-upstream-kasan-gce-root
2018/06/27 00:05 upstream 813835028e9a b0294c53 .config console log report ci-upstream-kasan-gce
2018/06/26 22:54 upstream 813835028e9a b0294c53 .config console log report ci-upstream-kasan-gce-root
2018/06/26 12:09 upstream 6f0d349d922b 2064fc5c .config console log report ci-upstream-kasan-gce-root
2018/06/26 07:57 upstream 6f0d349d922b 2064fc5c .config console log report ci-upstream-kasan-gce-root
2018/06/26 00:09 upstream 6f0d349d922b 2064fc5c .config console log report ci-upstream-kasan-gce
2018/06/25 21:38 upstream 6f0d349d922b 2064fc5c .config console log report ci-upstream-kasan-gce
2018/06/25 13:13 upstream 6f0d349d922b 2064fc5c .config console log report ci-upstream-kasan-gce
2018/06/25 01:56 upstream 7daf201d7fe8 2064fc5c .config console log report ci-upstream-kasan-gce-root
2018/06/24 15:29 upstream 77072ca59fdd 2064fc5c .config console log report ci-upstream-kasan-gce-root
2018/06/24 11:46 upstream 77072ca59fdd 2064fc5c .config console log report ci-upstream-kasan-gce
2018/06/24 10:46 upstream 77072ca59fdd 2064fc5c .config console log report ci-upstream-kasan-gce-root
2018/06/24 00:28 upstream 5e2204832b20 2064fc5c .config console log report ci-upstream-kasan-gce
2018/06/22 14:51 upstream 894b8c000ae6 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/22 07:56 upstream 27db64f65f1b 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/22 06:56 upstream 27db64f65f1b 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/21 20:02 upstream 1abd8a8f39cd 095ef806 .config console log report ci-upstream-kasan-gce-root
2018/06/21 18:25 upstream 1abd8a8f39cd 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/21 14:17 upstream 1abd8a8f39cd 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/21 11:04 upstream 1abd8a8f39cd 095ef806 .config console log report ci-upstream-kasan-gce-root
2018/06/21 07:46 upstream 1abd8a8f39cd 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/21 02:17 upstream 1abd8a8f39cd 095ef806 .config console log report ci-upstream-kasan-gce-root
2018/06/20 22:33 upstream 81e97f01371f 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/20 12:50 upstream 81e97f01371f 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/20 11:15 upstream 81e97f01371f 095ef806 .config console log report ci-upstream-kasan-gce-root
2018/06/20 06:32 upstream ba4dbdedd3ed 095ef806 .config console log report ci-upstream-kasan-gce-root
2018/06/20 01:50 upstream ba4dbdedd3ed 095ef806 .config console log report ci-upstream-kasan-gce
2018/06/19 21:27 upstream ba4dbdedd3ed 732e4256 .config console log report ci-upstream-kasan-gce
2018/06/19 14:19 upstream ba4dbdedd3ed 732e4256 .config console log report ci-upstream-kasan-gce
2018/06/18 17:22 upstream 9ffc59d57228 27c5f59f .config console log report ci-upstream-kasan-gce
2018/06/18 16:10 upstream 9ffc59d57228 27c5f59f .config console log report ci-upstream-kasan-gce
2018/06/07 10:08 upstream 1c8c5a9d38f6 d2ba33fa .config console log report ci-upstream-kasan-gce-root
2018/06/27 16:40 upstream 813835028e9a 43e60f7e .config console log report ci-upstream-kasan-gce-386
2018/06/26 04:41 upstream 6f0d349d922b 2064fc5c .config console log report ci-upstream-kasan-gce-386
2018/06/25 18:31 upstream 6f0d349d922b 2064fc5c .config console log report ci-upstream-kasan-gce-386
2018/06/25 15:18 upstream 6f0d349d922b 2064fc5c .config console log report ci-upstream-kasan-gce-386
2018/06/24 13:17 upstream 77072ca59fdd 2064fc5c .config console log report ci-upstream-kasan-gce-386
2018/06/24 01:44 upstream 5e2204832b20 2064fc5c .config console log report ci-upstream-kasan-gce-386
2018/06/22 05:01 upstream 27db64f65f1b 095ef806 .config console log report ci-upstream-kasan-gce-386
2018/06/21 13:12 upstream 1abd8a8f39cd 095ef806 .config console log report ci-upstream-kasan-gce-386
2018/06/21 10:03 upstream 1abd8a8f39cd 095ef806 .config console log report ci-upstream-kasan-gce-386
2018/06/20 18:12 upstream 81e97f01371f 095ef806 .config console log report ci-upstream-kasan-gce-386
2018/06/19 18:54 upstream ba4dbdedd3ed 732e4256 .config console log report ci-upstream-kasan-gce-386
2018/06/19 16:30 upstream ba4dbdedd3ed 732e4256 .config console log report ci-upstream-kasan-gce-386
2018/06/19 08:29 upstream ba4dbdedd3ed 45c54f75 .config console log report ci-upstream-kasan-gce-386
2018/06/19 02:25 upstream ba4dbdedd3ed 45c54f75 .config console log report ci-upstream-kasan-gce-386
* Struck through repros no longer work on HEAD.