syzbot


WARNING: suspicious RCU usage in xfrm_get_spdinfo

Status: fixed on 2019/11/03 21:23
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+bfb3cbc2e9467b566c8b@syzkaller.appspotmail.com
Fix commit: f10e0010fae8 net: xfrm: Add '_rcu' tag for rcu protected pointer in netns_xfrm
First crash: 1900d, last: 1897d
Cause bisection: introduced by (bisect log) :
commit f10e0010fae8174dc20bdc872bcaa85baa925cb7
Author: Su Yanjun <suyj.fnst@cn.fujitsu.com>
Date: Thu Mar 7 01:54:08 2019 +0000

  net: xfrm: Add '_rcu' tag for rcu protected pointer in netns_xfrm

Crash: WARNING: suspicious RCU usage in xfrm_get_spdinfo (log)
Repro: C syz .config
  
Fix bisection: failed (error log, bisect log)
  
Discussions (3)
Title Replies (including bot) Last reply
Reminder: 26 open syzbot bugs in "net/xfrm" subsystem 1 (1) 2019/07/24 01:42
Reminder: 27 open syzbot bugs in "net/xfrm" subsystem 1 (1) 2019/06/25 05:51
WARNING: suspicious RCU usage in xfrm_get_spdinfo 0 (2) 2019/03/19 20:57

Sample crash report:
=============================
WARNING: suspicious RCU usage
5.1.0-rc1-next-20190318 #5 Not tainted
-----------------------------
net/xfrm/xfrm_user.c:1080 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz-executor615/7788:
 #0: 00000000d9f69f58 (&net->xfrm.xfrm_cfg_mutex){+.+.}, at: xfrm_netlink_rcv+0x61/0x90 net/xfrm/xfrm_user.c:2691

stack backtrace:
CPU: 1 PID: 7788 Comm: syz-executor615 Not tainted 5.1.0-rc1-next-20190318 #5
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+0x172/0x1f0 lib/dump_stack.c:113
 lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5162
 xfrm_nlmsg_unicast net/xfrm/xfrm_user.c:1080 [inline]
 xfrm_get_spdinfo+0x923/0xb20 net/xfrm/xfrm_user.c:1214
 xfrm_user_rcv_msg+0x458/0x770 net/xfrm/xfrm_user.c:2684
 netlink_rcv_skb+0x17a/0x460 net/netlink/af_netlink.c:2485
 xfrm_netlink_rcv+0x70/0x90 net/xfrm/xfrm_user.c:2692
 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
 netlink_unicast+0x536/0x720 net/netlink/af_netlink.c:1336
 netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1925
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:661
 ___sys_sendmsg+0x806/0x930 net/socket.c:2260
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2298
 __do_sys_sendmsg net/socket.c:2307 [inline]
 __se_sys_sendmsg net/socket.c:2305 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2305
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4401d9
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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffc72c76dd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401d9
RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000

Crashes (46):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/03/18 16:27 linux-next b99981945914 4656beca .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2019/03/21 02:45 linux-next 835727301ed3 a664c187 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/21 00:44 linux-next 835727301ed3 a664c187 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 21:28 linux-next 835727301ed3 a664c187 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 20:11 linux-next 835727301ed3 a664c187 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 17:52 linux-next 835727301ed3 a664c187 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 17:52 linux-next 835727301ed3 a664c187 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 15:13 linux-next 835727301ed3 a664c187 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 14:52 linux-next 835727301ed3 a664c187 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 13:56 linux-next 835727301ed3 a664c187 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 13:05 linux-next 835727301ed3 a664c187 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 12:13 linux-next 835727301ed3 142c38ee .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 11:49 linux-next 835727301ed3 142c38ee .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 06:38 linux-next 835727301ed3 2458c1c6 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 05:40 linux-next 835727301ed3 2458c1c6 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 03:15 linux-next 75e6a83b189c 2458c1c6 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 01:16 linux-next 75e6a83b189c 2458c1c6 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 01:03 linux-next 75e6a83b189c 2458c1c6 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/20 00:38 linux-next 75e6a83b189c 2458c1c6 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 17:52 linux-next 75e6a83b189c e4549234 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 16:25 linux-next 75e6a83b189c e4549234 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 14:32 linux-next 75e6a83b189c e4549234 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 12:46 linux-next 75e6a83b189c e4549234 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 12:44 linux-next 75e6a83b189c e4549234 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 12:36 linux-next 75e6a83b189c e4549234 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 12:26 linux-next 75e6a83b189c e4549234 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 12:16 linux-next 75e6a83b189c e4549234 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 06:31 linux-next 75e6a83b189c 46264c32 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 06:27 linux-next 75e6a83b189c 46264c32 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 06:25 linux-next 75e6a83b189c 46264c32 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 06:19 linux-next 75e6a83b189c 46264c32 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 06:16 linux-next 75e6a83b189c 46264c32 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 06:15 linux-next 75e6a83b189c 46264c32 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 03:33 linux-next b99981945914 46264c32 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 03:31 linux-next b99981945914 46264c32 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 00:54 linux-next b99981945914 46264c32 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 00:50 linux-next b99981945914 46264c32 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 00:25 linux-next b99981945914 46264c32 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/19 00:18 linux-next b99981945914 46264c32 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/18 23:01 linux-next b99981945914 4656beca .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/18 22:26 linux-next b99981945914 4656beca .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/18 15:05 linux-next b99981945914 4656beca .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/18 14:59 linux-next b99981945914 4656beca .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/18 14:27 linux-next b99981945914 4656beca .config console log report ci-upstream-linux-next-kasan-gce-root
2019/03/18 14:12 linux-next b99981945914 4656beca .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.