Subject: [syzbot] WARNING in nsim_dev_reload_destroy

From: syzbot <[email-masked]>
Date: Sat, 23 Oct 2021 12:54:25 -0700

Hello,

syzbot found the following issue on:

HEAD commit:    0998aee279c3 Merge branch 'delete-impossible-devlink-notif..
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=115dd272b00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d36d2402e8523638
dashboard link: https://syzkaller.appspot.com/bug?extid=93d5accfaefceedf43c1
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=156b91acb00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=153aefb4b00000

The issue was bisected to:

commit 22849b5ea5952d853547cc5e0651f34a246b2a4f
Author: Leon Romanovsky <[email-masked]>
Date:   Thu Oct 21 14:16:14 2021 +0000

    devlink: Remove not-executed trap policer notifications

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=12450a72b00000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=11450a72b00000
console output: https://syzkaller.appspot.com/x/log.txt?x=16450a72b00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]
Fixes: 22849b5ea595 ("devlink: Remove not-executed trap policer notifications")

netdevsim netdevsim0 netdevsim2 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim0 netdevsim1 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim0 netdevsim0 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
------------[ cut here ]------------
WARNING: CPU: 0 PID: 6553 at net/core/devlink.c:11162 devlink_trap_groups_unregister+0xe8/0x110 net/core/devlink.c:11162
Modules linked in:
CPU: 0 PID: 6553 Comm: syz-executor166 Not tainted 5.15.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:devlink_trap_groups_unregister+0xe8/0x110 net/core/devlink.c:11162
Code: ff ff 31 ff 89 de e8 97 e3 41 fa 83 fb ff 75 cc e8 4d dc 41 fa 4c 89 f7 5b 5d 41 5c 41 5d 41 5e e9 6d 79 05 02 e8 38 dc 41 fa <0f> 0b e9 71 ff ff ff 4c 89 ef e8 19 4f 89 fa e9 3b ff ff ff 48 89
RSP: 0018:ffffc90002d8f3b0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000000000
RDX: ffff888024a00000 RSI: ffffffff87350e68 RDI: 0000000000000003
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: ffffffff87350dd7 R11: 0000000000000000 R12: ffffffff8a263c20
R13: ffff888077d36000 R14: dffffc0000000000 R15: ffff888077d36388
FS:  000055555711e300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200004c0 CR3: 0000000070465000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 nsim_dev_traps_exit+0x67/0x170 drivers/net/netdevsim/dev.c:849
 nsim_dev_reload_destroy+0x20c/0x2f0 drivers/net/netdevsim/dev.c:1559
 nsim_dev_reload_down+0xdf/0x180 drivers/net/netdevsim/dev.c:883
 devlink_reload+0x53b/0x6b0 net/core/devlink.c:4040
 devlink_nl_cmd_reload+0x6ed/0x11d0 net/core/devlink.c:4161
 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:731
 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
 genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:792
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2491
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x86d/0xda0 net/netlink/af_netlink.c:1916
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f02abf45409
Code: 28 c3 e8 4a 15 00 00 66 2e 0f 1f 84 00 00 00 00 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffeed83e458 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ffeed83e468 RCX: 00007f02abf45409
RDX: 0000000000000000 RSI: 0000000020000600 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffeed83e470
R13: 00007ffeed83e490 R14: 0000000000000000 R15: 0000000000000000

---
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