syzbot

==================================================================
BUG: KCSAN: data-race in can_can_gw_rcv / can_can_gw_rcv

read-write to 0xffff88815d9e8f80 of 4 bytes by interrupt on cpu 0:
 can_can_gw_rcv+0x863/0x870 net/can/gw.c:572
 deliver net/can/af_can.c:575 [inline]
 can_rcv_filter+0xc3/0x480 net/can/af_can.c:602
 can_receive+0x13e/0x190 net/can/af_can.c:674
 can_rcv+0x17d/0x1f0 net/can/af_can.c:699
 __netif_receive_skb_one_core net/core/dev.c:6202 [inline]
 __netif_receive_skb net/core/dev.c:6315 [inline]
 process_backlog+0x363/0x670 net/core/dev.c:6666
 __napi_poll+0x61/0x300 net/core/dev.c:7733
 napi_poll net/core/dev.c:7796 [inline]
 net_rx_action+0x452/0x930 net/core/dev.c:7953
 handle_softirqs+0xb9/0x280 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x42/0xd0 kernel/softirq.c:735
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0x74/0x80 arch/x86/kernel/apic/apic.c:1061
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 __sanitizer_cov_trace_const_cmp8+0x8/0x90 kernel/kcov.c:322
 nd_jump_root+0x31/0x270 fs/namei.c:1129
 path_init+0x2b0/0x9f0 fs/namei.c:2716
 path_openat+0xe7/0x2050 fs/namei.c:4853
 do_file_open+0x16c/0x290 fs/namei.c:4887
 do_sys_openat2+0x94/0x130 fs/open.c:1364
 do_sys_open fs/open.c:1370 [inline]
 __do_sys_openat fs/open.c:1386 [inline]
 __se_sys_openat fs/open.c:1381 [inline]
 __x64_sys_openat+0xf2/0x120 fs/open.c:1381
 x64_sys_call+0x1e39/0x3020 arch/x86/include/generated/asm/syscalls_64.h:258
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read-write to 0xffff88815d9e8f80 of 4 bytes by interrupt on cpu 1:
 can_can_gw_rcv+0x863/0x870 net/can/gw.c:572
 deliver net/can/af_can.c:575 [inline]
 can_rcv_filter+0xc3/0x480 net/can/af_can.c:602
 can_receive+0x13e/0x190 net/can/af_can.c:674
 can_rcv+0x17d/0x1f0 net/can/af_can.c:699
 __netif_receive_skb_one_core net/core/dev.c:6202 [inline]
 __netif_receive_skb net/core/dev.c:6315 [inline]
 process_backlog+0x363/0x670 net/core/dev.c:6666
 __napi_poll+0x61/0x300 net/core/dev.c:7733
 napi_poll net/core/dev.c:7796 [inline]
 net_rx_action+0x452/0x930 net/core/dev.c:7953
 handle_softirqs+0xb9/0x280 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x42/0xd0 kernel/softirq.c:735
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0x74/0x80 arch/x86/kernel/apic/apic.c:1061
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 import_iovec+0x5/0x80 lib/iov_iter.c:1439
 copy_msghdr_from_user net/socket.c:2635 [inline]
 recvmsg_copy_msghdr net/socket.c:2884 [inline]
 ___sys_recvmsg+0x394/0x3b0 net/socket.c:2956
 do_recvmmsg+0x1ef/0x560 net/socket.c:3055
 __sys_recvmmsg net/socket.c:3129 [inline]
 __do_sys_recvmmsg net/socket.c:3152 [inline]
 __se_sys_recvmmsg net/socket.c:3145 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3145
 x64_sys_call+0x80f/0x3020 arch/x86/include/generated/asm/syscalls_64.h:300
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00003469 -> 0x0000346a

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 19459 Comm: syz.6.4553 Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
==================================================================
==================================================================
BUG: KCSAN: data-race in can_can_gw_rcv / can_can_gw_rcv

read-write to 0xffff88815d9e8f80 of 4 bytes by interrupt on cpu 0:
 can_can_gw_rcv+0x863/0x870 net/can/gw.c:572
 deliver net/can/af_can.c:575 [inline]
 can_rcv_filter+0xc3/0x480 net/can/af_can.c:602
 can_receive+0x13e/0x190 net/can/af_can.c:674
 can_rcv+0x17d/0x1f0 net/can/af_can.c:699
 __netif_receive_skb_one_core net/core/dev.c:6202 [inline]
 __netif_receive_skb net/core/dev.c:6315 [inline]
 process_backlog+0x363/0x670 net/core/dev.c:6666
 __napi_poll+0x61/0x300 net/core/dev.c:7733
 napi_poll net/core/dev.c:7796 [inline]
 net_rx_action+0x452/0x930 net/core/dev.c:7953
 handle_softirqs+0xb9/0x280 kernel/softirq.c:622
 do_softirq+0x45/0x60 kernel/softirq.c:523
 __local_bh_enable_ip+0x70/0x80 kernel/softirq.c:450
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 __alloc_skb+0x658/0x690 net/core/skbuff.c:697
 alloc_skb include/linux/skbuff.h:1385 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline]
 nsim_dev_trap_report_work+0x18a/0x640 drivers/net/netdevsim/dev.c:922
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0x4f0/0x9c0 kernel/workqueue.c:3397
 worker_thread+0x58a/0x780 kernel/workqueue.c:3478
 kthread+0x22a/0x280 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read-write to 0xffff88815d9e8f80 of 4 bytes by interrupt on cpu 1:
 can_can_gw_rcv+0x863/0x870 net/can/gw.c:572
 deliver net/can/af_can.c:575 [inline]
 can_rcv_filter+0xc3/0x480 net/can/af_can.c:602
 can_receive+0x13e/0x190 net/can/af_can.c:674
 can_rcv+0x17d/0x1f0 net/can/af_can.c:699
 __netif_receive_skb_one_core net/core/dev.c:6202 [inline]
 __netif_receive_skb net/core/dev.c:6315 [inline]
 process_backlog+0x363/0x670 net/core/dev.c:6666
 __napi_poll+0x61/0x300 net/core/dev.c:7733
 napi_poll net/core/dev.c:7796 [inline]
 net_rx_action+0x452/0x930 net/core/dev.c:7953
 handle_softirqs+0xb9/0x280 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x42/0xd0 kernel/softirq.c:735
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0x74/0x80 arch/x86/kernel/apic/apic.c:1061
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 kcsan_setup_watchpoint+0x404/0x410 kernel/kcsan/core.c:705
 __tlb_remove_folio_pages_size mm/mmu_gather.c:-1 [inline]
 __tlb_remove_folio_pages+0x7b/0x220 mm/mmu_gather.c:210
 zap_present_folio_ptes mm/memory.c:1677 [inline]
 zap_present_ptes mm/memory.c:1730 [inline]
 do_zap_pte_range mm/memory.c:1832 [inline]
 zap_pte_range mm/memory.c:1934 [inline]
 zap_pmd_range mm/memory.c:2020 [inline]
 zap_pud_range mm/memory.c:2048 [inline]
 zap_p4d_range mm/memory.c:2069 [inline]
 __zap_vma_range+0x14f1/0x2c20 mm/memory.c:2109
 unmap_vmas+0x22a/0x340 mm/memory.c:2178
 exit_mmap+0x1ab/0x5f0 mm/mmap.c:1300
 __mmput+0x28/0x1c0 kernel/fork.c:1178
 mmput+0x40/0x50 kernel/fork.c:1201
 exit_mm+0x15f/0x1f0 kernel/exit.c:582
 do_exit+0x442/0x1530 kernel/exit.c:964
 __do_sys_exit kernel/exit.c:1086 [inline]
 __se_sys_exit kernel/exit.c:1084 [inline]
 __x64_sys_exit+0x1f/0x20 kernel/exit.c:1084
 x64_sys_call+0x301d/0x3020 arch/x86/include/generated/asm/syscalls_64.h:61
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0003b852 -> 0x0003b853

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 19466 Comm: syz.1.4554 Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
==================================================================
==================================================================
BUG: KCSAN: data-race in can_can_gw_rcv / can_can_gw_rcv

read-write to 0xffff88815d9e8f80 of 4 bytes by interrupt on cpu 0:
 can_can_gw_rcv+0x863/0x870 net/can/gw.c:572
 deliver net/can/af_can.c:575 [inline]
 can_rcv_filter+0xc3/0x480 net/can/af_can.c:602
 can_receive+0x13e/0x190 net/can/af_can.c:674
 can_rcv+0x17d/0x1f0 net/can/af_can.c:699
 __netif_receive_skb_one_core net/core/dev.c:6202 [inline]
 __netif_receive_skb net/core/dev.c:6315 [inline]
 process_backlog+0x363/0x670 net/core/dev.c:6666
 __napi_poll+0x61/0x300 net/core/dev.c:7733
 napi_poll net/core/dev.c:7796 [inline]
 net_rx_action+0x452/0x930 net/core/dev.c:7953
 handle_softirqs+0xb9/0x280 kernel/softirq.c:622
 do_softirq+0x45/0x60 kernel/softirq.c:523
 __local_bh_enable_ip+0x70/0x80 kernel/softirq.c:450
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 update_defense_level+0x59d/0x5d0 net/netfilter/ipvs/ip_vs_ctl.c:210
 defense_work_handler+0x1f/0x80 net/netfilter/ipvs/ip_vs_ctl.c:235
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0x4f0/0x9c0 kernel/workqueue.c:3397
 worker_thread+0x58a/0x780 kernel/workqueue.c:3478
 kthread+0x22a/0x280 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read-write to 0xffff88815d9e8f80 of 4 bytes by interrupt on cpu 1:
 can_can_gw_rcv+0x863/0x870 net/can/gw.c:572
 deliver net/can/af_can.c:575 [inline]
 can_rcv_filter+0xc3/0x480 net/can/af_can.c:602
 can_receive+0x13e/0x190 net/can/af_can.c:674
 can_rcv+0x17d/0x1f0 net/can/af_can.c:699
 __netif_receive_skb_one_core net/core/dev.c:6202 [inline]
 __netif_receive_skb net/core/dev.c:6315 [inline]
 process_backlog+0x363/0x670 net/core/dev.c:6666
 __napi_poll+0x61/0x300 net/core/dev.c:7733
 napi_poll net/core/dev.c:7796 [inline]
 net_rx_action+0x452/0x930 net/core/dev.c:7953
 handle_softirqs+0xb9/0x280 kernel/softirq.c:622
 do_softirq+0x45/0x60 kernel/softirq.c:523
 __local_bh_enable_ip+0x70/0x80 kernel/softirq.c:450
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 __alloc_skb+0x658/0x690 net/core/skbuff.c:697
 alloc_skb include/linux/skbuff.h:1385 [inline]
 alloc_skb_with_frags+0x7e/0x3d0 net/core/skbuff.c:6766
 sock_alloc_send_pskb+0x44d/0x500 net/core/sock.c:3002
 unix_dgram_sendmsg+0x391/0x1050 net/unix/af_unix.c:2141
 unix_seqpacket_sendmsg+0xd1/0x110 net/unix/af_unix.c:2542
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 sock_write_iter+0x2e8/0x320 net/socket.c:1254
 do_iter_readv_writev+0x4fd/0x5a0 fs/read_write.c:-1
 vfs_writev+0x2e1/0x900 fs/read_write.c:1059
 do_writev+0xe9/0x210 fs/read_write.c:1105
 __do_sys_writev fs/read_write.c:1173 [inline]
 __se_sys_writev fs/read_write.c:1170 [inline]
 __x64_sys_writev+0x45/0x50 fs/read_write.c:1170
 x64_sys_call+0x1c0c/0x3020 arch/x86/include/generated/asm/syscalls_64.h:21
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00077d9e -> 0x00077d9f

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 101 PID: 3020 Comm: dhcpcd Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
==================================================================