syzbot


KMSAN: uninit-value in tomoyo_check_unix_address

Status: fixed on 2019/05/27 12:48
Subsystems: tomoyo
[Documentation on labels]
Reported-by: syzbot+e9687dbb0b6b2057d0ed@syzkaller.appspotmail.com
Fix commit: e6193f78bb68 tomoyo: Check address length before reading address family
First crash: 1778d, last: 1777d
Discussions (1)
Title Replies (including bot) Last reply
KMSAN: uninit-value in tomoyo_check_unix_address 0 (1) 2019/05/16 12:58

Sample crash report:
==================================================================
BUG: KMSAN: uninit-value in tomoyo_check_unix_address+0x36a/0xa30 security/tomoyo/network.c:597
CPU: 1 PID: 16323 Comm: syz-executor.1 Not tainted 5.1.0+ #3
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+0x191/0x1f0 lib/dump_stack.c:113
 kmsan_report+0x130/0x2a0 mm/kmsan/kmsan.c:619
 __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:310
 tomoyo_check_unix_address+0x36a/0xa30 security/tomoyo/network.c:597
 tomoyo_socket_bind_permission+0x2a2/0x3b0 security/tomoyo/network.c:740
 tomoyo_socket_bind+0x8b/0xa0 security/tomoyo/tomoyo.c:471
 security_socket_bind+0x127/0x200 security/security.c:1943
 __sys_bind+0x536/0x7c0 net/socket.c:1623
 __do_sys_bind net/socket.c:1638 [inline]
 __se_sys_bind+0x8d/0xb0 net/socket.c:1636
 __x64_sys_bind+0x4a/0x70 net/socket.c:1636
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x458da9
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fc4912efc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000031
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458da9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc4912f06d4
R13: 00000000004beec4 R14: 00000000004cffd0 R15: 00000000ffffffff

Local variable description: ----address@__sys_bind
Variable was created at:
 sockfd_lookup_light net/socket.c:488 [inline]
 __sys_bind+0x8c/0x7c0 net/socket.c:1619
 __do_sys_bind net/socket.c:1638 [inline]
 __se_sys_bind+0x8d/0xb0 net/socket.c:1636
==================================================================

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/05/16 16:14 https://github.com/google/kmsan.git master 3b955a409bf3 f59a9cb5 .config console log report ci-upstream-kmsan-gce
2019/05/16 14:07 https://github.com/google/kmsan.git master 3b955a409bf3 f59a9cb5 .config console log report ci-upstream-kmsan-gce
2019/05/16 13:30 https://github.com/google/kmsan.git master 3b955a409bf3 f59a9cb5 .config console log report ci-upstream-kmsan-gce
2019/05/16 13:23 https://github.com/google/kmsan.git master 3b955a409bf3 f59a9cb5 .config console log report ci-upstream-kmsan-gce
2019/05/16 11:27 https://github.com/google/kmsan.git master 3b955a409bf3 f59a9cb5 .config console log report ci-upstream-kmsan-gce
2019/05/16 11:15 https://github.com/google/kmsan.git master 3b955a409bf3 f59a9cb5 .config console log report ci-upstream-kmsan-gce
2019/05/16 11:11 https://github.com/google/kmsan.git master 3b955a409bf3 f59a9cb5 .config console log report ci-upstream-kmsan-gce
2019/05/16 10:40 https://github.com/google/kmsan.git master 3b955a409bf3 f59a9cb5 .config console log report ci-upstream-kmsan-gce
* Struck through repros no longer work on HEAD.