syzbot


KASAN: slab-out-of-bounds Read in __sctp_v6_cmp_addr

Status: fixed on 2018/05/16 09:57
Subsystems: sctp
[Documentation on labels]
Reported-by: syzbot+cd494c1dd681d4d93ebb@syzkaller.appspotmail.com
Fix commit: d625329b06e4 sctp: handle two v4 addrs comparison in sctp_inet6_cmp_addr
First crash: 2249d, last: 2235d
Discussions (7)
Title Replies (including bot) Last reply
[PATCH 3.16 000/366] 3.16.60-rc1 review 370 (370) 2019/03/29 15:47
[PATCH 4.4 00/92] 4.4.133-stable review 126 (126) 2018/11/01 21:45
[PATCH 4.16 00/55] 4.16.10-stable review 63 (63) 2018/05/19 07:43
[PATCH 4.9 00/33] 4.9.101-stable review 40 (40) 2018/05/18 20:47
[PATCH 4.14 00/45] 4.14.42-stable review 50 (50) 2018/05/18 20:46
[PATCH net] sctp: handle two v4 addrs comparison in sctp_inet6_cmp_addr 4 (4) 2018/04/27 17:22
KASAN: slab-out-of-bounds Read in __sctp_v6_cmp_addr 1 (2) 2018/04/23 06:56

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 ipv6_addr_equal include/net/ipv6.h:507 [inline]
BUG: KASAN: slab-out-of-bounds in __sctp_v6_cmp_addr+0x4c7/0x530 net/sctp/ipv6.c:580
Read of size 8 at addr ffff8801b4bb98e0 by task syz-executor112/4517

CPU: 1 PID: 4517 Comm: syz-executor112 Not tainted 4.17.0-rc2+ #19
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_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 ipv6_addr_equal include/net/ipv6.h:507 [inline]
 __sctp_v6_cmp_addr+0x4c7/0x530 net/sctp/ipv6.c:580
 sctp_inet6_cmp_addr+0x169/0x1a0 net/sctp/ipv6.c:898
 sctp_bind_addr_match+0x20b/0x400 net/sctp/bind_addr.c:330
 sctp_do_bind+0x1c0/0x5f0 net/sctp/socket.c:427
 sctp_bindx_add+0x90/0x1a0 net/sctp/socket.c:529
 sctp_setsockopt_bindx+0x2ad/0x320 net/sctp/socket.c:1058
 sctp_setsockopt+0x12c4/0x7000 net/sctp/socket.c:4227
 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3039
 __sys_setsockopt+0x1bd/0x390 net/socket.c:1903
 __do_sys_setsockopt net/socket.c:1914 [inline]
 __se_sys_setsockopt net/socket.c:1911 [inline]
 __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1911
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x43fda9
RSP: 002b:00007fff11cbd088 EFLAGS: 00000217 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fda9
RDX: 0000000000000064 RSI: 0000000000000084 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000020 R09: 00000000004002c8
R10: 0000000020d24000 R11: 0000000000000217 R12: 00000000004016d0
R13: 0000000000401760 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 4517:
 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_node mm/slab.c:3682 [inline]
 __kmalloc_node+0x47/0x70 mm/slab.c:3689
 kmalloc_node include/linux/slab.h:554 [inline]
 kvmalloc_node+0x6b/0x100 mm/util.c:421
 kvmalloc include/linux/mm.h:550 [inline]
 vmemdup_user+0x2d/0xa0 mm/util.c:186
 sctp_setsockopt_bindx+0x5d/0x320 net/sctp/socket.c:1022
 sctp_setsockopt+0x12c4/0x7000 net/sctp/socket.c:4227
 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3039
 __sys_setsockopt+0x1bd/0x390 net/socket.c:1903
 __do_sys_setsockopt net/socket.c:1914 [inline]
 __se_sys_setsockopt net/socket.c:1911 [inline]
 __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1911
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 2811:
 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+0x34d/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:191 [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 ffff8801b4bb98c0
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes to the right of
 32-byte region [ffff8801b4bb98c0, ffff8801b4bb98e0)
The buggy address belongs to the page:
page:ffffea0006d2ee40 count:1 mapcount:0 mapping:ffff8801b4bb9000 index:0xffff8801b4bb9fc1
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801b4bb9000 ffff8801b4bb9fc1 000000010000003a
raw: ffffea00075c26e0 ffffea000766f460 ffff8801da8001c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b4bb9780: fb fb fb fb fc fc fc fc 00 fc fc fc fc fc fc fc
 ffff8801b4bb9800: 00 03 fc fc fc fc fc fc fb fb fb fb fc fc fc fc
>ffff8801b4bb9880: fb fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc
                                                       ^
 ffff8801b4bb9900: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
 ffff8801b4bb9980: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc
==================================================================

Crashes (3202):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/04/27 09:28 upstream 0644f186fc9d 73417389 .config console log report syz C ci-upstream-kasan-gce-root
2018/04/26 08:03 upstream 26ed24e429d8 73417389 .config console log report syz C ci-upstream-kasan-gce
2018/04/21 17:32 upstream 83beed7b2b26 d23fcf6c .config console log report syz C ci-upstream-kasan-gce-root
2018/04/21 16:52 upstream 83beed7b2b26 d23fcf6c .config console log report syz C ci-upstream-kasan-gce-root
2018/04/21 08:59 upstream 83beed7b2b26 ca03d688 .config console log report syz C ci-upstream-kasan-gce
2018/04/21 04:13 upstream 83beed7b2b26 ca03d688 .config console log report syz C ci-upstream-kasan-gce
2018/04/21 03:15 upstream 83beed7b2b26 ca03d688 .config console log report syz C ci-upstream-kasan-gce-root
2018/04/21 03:07 upstream 83beed7b2b26 ca03d688 .config console log report syz C ci-upstream-kasan-gce
2018/04/25 19:07 net-next-old c749fa181bd5 73417389 .config console log report syz C ci-upstream-net-kasan-gce
2018/05/01 15:33 upstream fff75eb2a08c d5b114b4 .config console log report syz ci-upstream-kasan-gce-386
2018/04/29 11:35 upstream cdface520934 d5a5d045 .config console log report syz ci-upstream-kasan-gce-386
2018/04/29 10:57 upstream cdface520934 d5a5d045 .config console log report syz ci-upstream-kasan-gce-386
2018/04/29 10:44 upstream cdface520934 d5a5d045 .config console log report syz ci-upstream-kasan-gce-386
2018/04/27 01:45 upstream 69bfd470f462 73417389 .config console log report ci-upstream-kasan-gce
2018/04/21 19:30 upstream 5e7c7806111a d23fcf6c .config console log report ci-upstream-kasan-gce
2018/04/21 08:50 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 08:46 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 08:38 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 08:23 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/04/21 07:56 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/04/21 07:47 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 07:43 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/04/21 07:33 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 06:41 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 06:33 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 06:12 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 05:57 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 05:30 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/04/21 04:19 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 02:47 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 02:41 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/04/21 02:38 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/04/21 02:36 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/04/21 02:35 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/04/21 02:35 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/04/21 02:27 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/04/21 02:19 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 02:17 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 02:15 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 02:15 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 02:14 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 02:13 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/04/21 02:12 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 02:11 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/04/21 02:11 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 02:08 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 02:07 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 02:04 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce
2018/04/21 02:01 upstream 83beed7b2b26 ca03d688 .config console log report ci-upstream-kasan-gce-root
2018/05/04 23:56 net-next-old b05f03b232ab 9ce14f4b .config console log report ci-upstream-net-kasan-gce
2018/04/29 18:11 net-next-old 9e8d438e8ba4 bb79c6ab .config console log report ci-upstream-net-kasan-gce
2018/04/26 00:57 net-next-old c8ad08929d1b 73417389 .config console log report ci-upstream-net-kasan-gce
2018/04/25 08:56 net-next-old c749fa181bd5 73417389 .config console log report ci-upstream-net-kasan-gce
2018/04/24 13:50 net-next-old 9c20b9372fba 2bf86f40 .config console log report ci-upstream-net-kasan-gce
2018/04/24 04:38 net-next-old b300fcf883ac e7e85d36 .config console log report ci-upstream-net-kasan-gce
2018/04/23 15:39 net-next-old a56e6bcd34b5 0d8e591c .config console log report ci-upstream-net-kasan-gce
2018/04/22 10:13 net-next-old e0ada51db907 d23fcf6c .config console log report ci-upstream-net-kasan-gce
* Struck through repros no longer work on HEAD.