Subject: [syzbot] [wireguard?] KCSAN: data-race in wg_packet_handshake_receive_worker / wg_packet_rx_poll (6)

From: syzbot <[email-masked]>
Date: Fri, 01 Dec 2023 07:31:23 -0800

Hello,

syzbot found the following issue on:

HEAD commit:    d2da77f431ac Merge tag 'parisc-for-6.7-rc3' of git://git.k..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11294880e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=8c1151391aefc0c3
dashboard link: https://syzkaller.appspot.com/bug?extid=57cb9d16a1b17521eb76
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0ebc29947781/disk-d2da77f4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a82ec858fbee/vmlinux-d2da77f4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d45f2fa85085/bzImage-d2da77f4.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]

==================================================================
BUG: KCSAN: data-race in wg_packet_handshake_receive_worker / wg_packet_rx_poll

read-write to 0xffff8881392abfa0 of 8 bytes by interrupt on cpu 1:
 update_rx_stats drivers/net/wireguard/receive.c:23 [inline]
 wg_packet_consume_data_done drivers/net/wireguard/receive.c:358 [inline]
 wg_packet_rx_poll+0xd35/0xf00 drivers/net/wireguard/receive.c:474
 __napi_poll+0x60/0x3b0 net/core/dev.c:6533
 napi_poll net/core/dev.c:6602 [inline]
 net_rx_action+0x32b/0x750 net/core/dev.c:6735
 __do_softirq+0xc4/0x279 kernel/softirq.c:553
 do_softirq+0x5e/0x90 kernel/softirq.c:454
 __local_bh_enable_ip+0x64/0x70 kernel/softirq.c:381
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
 _raw_spin_unlock_bh+0x36/0x40 kernel/locking/spinlock.c:210
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline]
 wg_packet_handshake_receive_worker+0x184/0x5e0 drivers/net/wireguard/receive.c:212
 process_one_work kernel/workqueue.c:2630 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
 worker_thread+0x525/0x730 kernel/workqueue.c:2784
 kthread+0x1d7/0x210 kernel/kthread.c:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

read-write to 0xffff8881392abfa0 of 8 bytes by task 22808 on cpu 0:
 update_rx_stats drivers/net/wireguard/receive.c:23 [inline]
 wg_receive_handshake_packet drivers/net/wireguard/receive.c:198 [inline]
 wg_packet_handshake_receive_worker+0x4b9/0x5e0 drivers/net/wireguard/receive.c:213
 process_one_work kernel/workqueue.c:2630 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
 worker_thread+0x525/0x730 kernel/workqueue.c:2784
 kthread+0x1d7/0x210 kernel/kthread.c:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

value changed: 0x00000000000070b0 -> 0x00000000000070d0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 22808 Comm: kworker/0:4 Not tainted 6.7.0-rc2-syzkaller-00265-gd2da77f431ac #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: wg-kex-wg2 wg_packet_handshake_receive_worker
==================================================================

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