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KCSAN: data-race in free_old_xmit_skbs / virtnet_stats (2)

Status: auto-obsoleted due to no activity on 2022/10/24 03:10
Subsystems: net virtualization
[Documentation on labels]
First crash: 556d, last: 556d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in free_old_xmit_skbs / virtnet_stats net virtualization 3 823d 833d 0/26 auto-closed as invalid on 2022/01/30 06:15
upstream KCSAN: data-race in free_old_xmit_skbs / virtnet_stats (3) net virtualization 1 254d 254d 0/26 auto-obsoleted due to no activity on 2023/08/22 14:25

Sample crash report:
==================================================================
BUG: KCSAN: data-race in free_old_xmit_skbs / virtnet_stats

read-write to 0xffff888100d8a6f0 of 8 bytes by interrupt on cpu 1:
 free_old_xmit_skbs+0x11f/0x180 drivers/net/virtio_net.c:1617
 virtnet_poll_tx+0x11a/0x280 drivers/net/virtio_net.c:1742
 __napi_poll+0x65/0x390 net/core/dev.c:6511
 napi_poll net/core/dev.c:6578 [inline]
 net_rx_action+0x37e/0x730 net/core/dev.c:6689
 __do_softirq+0x158/0x2e3 kernel/softirq.c:571
 __irq_exit_rcu kernel/softirq.c:650 [inline]
 irq_exit_rcu+0x41/0x70 kernel/softirq.c:662
 common_interrupt+0x9f/0xc0 arch/x86/kernel/irq.c:240
 asm_common_interrupt+0x22/0x40
 schedule_debug kernel/sched/core.c:5736 [inline]
 __schedule+0x49/0x6e0 kernel/sched/core.c:6388
 schedule+0x51/0x80 kernel/sched/core.c:6570
 schedule_hrtimeout_range_clock+0xfc/0x1d0 kernel/time/hrtimer.c:2305
 schedule_hrtimeout_range+0x25/0x30 kernel/time/hrtimer.c:2351
 poll_schedule_timeout fs/select.c:244 [inline]
 do_select+0xf87/0x1020 fs/select.c:607
 core_sys_select+0x368/0x520 fs/select.c:681
 do_pselect fs/select.c:763 [inline]
 __do_sys_pselect6+0x1f4/0x250 fs/select.c:804
 __se_sys_pselect6 fs/select.c:795 [inline]
 __x64_sys_pselect6+0x74/0x80 fs/select.c:795
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888100d8a6f0 of 8 bytes by task 1473 on cpu 0:
 virtnet_stats+0x15f/0x350 drivers/net/virtio_net.c:2071
 dev_get_stats+0x6a/0x290 net/core/dev.c:10451
 rtnl_fill_stats+0x45/0x320 net/core/rtnetlink.c:1242
 rtnl_fill_ifinfo+0xbff/0xfe0 net/core/rtnetlink.c:1819
 rtnl_dump_ifinfo+0x87c/0xcb0 net/core/rtnetlink.c:2186
 netlink_dump+0x38c/0x720 net/netlink/af_netlink.c:2275
 netlink_recvmsg+0x432/0x740 net/netlink/af_netlink.c:2002
 ____sys_recvmsg+0x162/0x2f0
 ___sys_recvmsg net/socket.c:2743 [inline]
 __sys_recvmsg+0x1a0/0x230 net/socket.c:2773
 __do_sys_recvmsg net/socket.c:2783 [inline]
 __se_sys_recvmsg net/socket.c:2780 [inline]
 __x64_sys_recvmsg+0x42/0x50 net/socket.c:2780
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000243a8d -> 0x0000000000243bbb

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1473 Comm: dhcpcd Not tainted 6.0.0-rc5-syzkaller-00097-g38eddeedbbea-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/09/19 03:05 upstream 38eddeedbbea dd9a85ff .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in free_old_xmit_skbs / virtnet_stats
* Struck through repros no longer work on HEAD.