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BUG: KCSAN: data-race in isotp_sendmsg / isotp_sendmsg

write to 0xffff8881079a24a4 of 4 bytes by task 3913 on cpu 0:
 isotp_sendmsg+0x35e/0xc00 net/can/isotp.c:1117
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x140/0x180 net/socket.c:745
 ____sys_sendmsg+0x312/0x410 net/socket.c:2597
 ___sys_sendmsg net/socket.c:2651 [inline]
 __sys_sendmmsg+0x269/0x500 net/socket.c:2737
 __do_sys_sendmmsg net/socket.c:2766 [inline]
 __se_sys_sendmmsg net/socket.c:2763 [inline]
 __x64_sys_sendmmsg+0x57/0x70 net/socket.c:2763
 x64_sys_call+0xa49/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881079a24a4 of 4 bytes by task 3908 on cpu 1:
 isotp_sendmsg+0xba/0xc00 net/can/isotp.c:950
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x140/0x180 net/socket.c:745
 ____sys_sendmsg+0x312/0x410 net/socket.c:2597
 ___sys_sendmsg net/socket.c:2651 [inline]
 __sys_sendmsg+0x1e9/0x280 net/socket.c:2680
 __do_sys_sendmsg net/socket.c:2689 [inline]
 __se_sys_sendmsg net/socket.c:2687 [inline]
 __x64_sys_sendmsg+0x46/0x50 net/socket.c:2687
 x64_sys_call+0x2689/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3908 Comm: syz.2.124 Not tainted 6.11.0-rc2-syzkaller-00013-gd4560686726f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
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