[syzbot] [wireguard?] KCSAN: data-race in wg_packet_handshake_receive_worker / wg_packet_rx_poll (5)

syzbot
2023-08-28T14:38:50Z

Hello,

syzbot found the following issue on:

HEAD commit: 93f5de5f648d Merge tag 'acpi-6.5-rc8' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10f3d75ba80000
kernel config: https://syzkaller.appspot.com/x/.config?x=f12c32a009b80107
dashboard link: https://syzkaller.appspot.com/bug?extid=80a98381230162731266
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/1f2b512883ff/disk-93f5de5f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e10aeb67696c/vmlinux-93f5de5f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3e95be907cb0/bzImage-93f5de5f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+80a98381230162731266@syzkaller.appspotmail.com

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

read-write to 0xffff88813939a178 of 8 bytes by interrupt on cpu 0:
wg_packet_rx_poll+0xb43/0xf80 drivers/net/wireguard/receive.c:474
__napi_poll+0x60/0x3b0 net/core/dev.c:6460
napi_poll net/core/dev.c:6527 [inline]
net_rx_action+0x32b/0x750 net/core/dev.c:6660
__do_softirq+0xc1/0x265 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+0x184/0x5d0 drivers/net/wireguard/receive.c:212
process_one_work+0x434/0x860 kernel/workqueue.c:2600
worker_thread+0x5f2/0xa10 kernel/workqueue.c:2751
kthread+0x1d7/0x210 kernel/kthread.c:389
ret_from_fork+0x2e/0x40 arch/x86/kernel/process.c:145
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

read-write to 0xffff88813939a178 of 8 bytes by task 8583 on cpu 1:
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+0x4b2/0x5d0 drivers/net/wireguard/receive.c:213
process_one_work+0x434/0x860 kernel/workqueue.c:2600
worker_thread+0x5f2/0xa10 kernel/workqueue.c:2751
kthread+0x1d7/0x210 kernel/kthread.c:389
ret_from_fork+0x2e/0x40 arch/x86/kernel/process.c:145
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

value changed: 0x00000000000077a0 -> 0x00000000000077c0

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8583 Comm: kworker/1:14 Tainted: G W 6.5.0-rc7-syzkaller-00024-g93f5de5f648d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Workqueue: wg-kex-wg2 wg_packet_handshake_receive_worker
==================================================================

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