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BUG: KMSAN: uninit-value in can_receive+0x12c/0x4a0 net/can/af_can.c:656
 can_receive+0x12c/0x4a0 net/can/af_can.c:656
 can_rcv+0x1ff/0x3b0 net/can/af_can.c:690
 __netif_receive_skb_one_core net/core/dev.c:5991 [inline]
 __netif_receive_skb+0x474/0xac0 net/core/dev.c:6104
 process_backlog+0x485/0xa00 net/core/dev.c:6456
 __napi_poll+0xdd/0x8a0 net/core/dev.c:7506
 napi_poll net/core/dev.c:7569 [inline]
 net_rx_action+0xa59/0x1ac0 net/core/dev.c:7696
 handle_softirqs+0x166/0x6e0 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x66/0x180 kernel/softirq.c:680
 irq_exit_rcu+0x12/0x20 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x84/0x90 arch/x86/kernel/apic/apic.c:1050
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:702
 __preempt_count_dec_and_test arch/x86/include/asm/preempt.h:95 [inline]
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock_irqrestore+0x33/0x60 kernel/locking/spinlock.c:194
 unlock_hrtimer_base kernel/time/hrtimer.c:1020 [inline]
 hrtimer_start_range_ns+0x149a/0x1900 kernel/time/hrtimer.c:1332
 hrtimer_start include/linux/hrtimer.h:263 [inline]
 j1939_tp_schedule_txtimer+0xc7/0x110 net/can/j1939/transport.c:703
 j1939_sk_send_loop net/can/j1939/socket.c:1166 [inline]
 j1939_sk_sendmsg+0x1bb4/0x2760 net/can/j1939/socket.c:1279
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x333/0x3d0 net/socket.c:729
 ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2614
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2703
 x64_sys_call+0x1dfd/0x3e20 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4186 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 __do_kmalloc_node mm/slub.c:4364 [inline]
 __kmalloc_node_track_caller_noprof+0x96d/0x12f0 mm/slub.c:4384
 kmalloc_reserve+0x22f/0x4b0 net/core/skbuff.c:600
 pskb_expand_head+0x1fc/0x1610 net/core/skbuff.c:2240
 netif_skb_check_for_xdp net/core/dev.c:5351 [inline]
 netif_receive_generic_xdp net/core/dev.c:5382 [inline]
 do_xdp_generic+0xa79/0x1690 net/core/dev.c:5450
 __netif_receive_skb_core+0x2524/0x6df0 net/core/dev.c:5801
 __netif_receive_skb_one_core net/core/dev.c:5989 [inline]
 __netif_receive_skb+0xcc/0xac0 net/core/dev.c:6104
 process_backlog+0x485/0xa00 net/core/dev.c:6456
 __napi_poll+0xdd/0x8a0 net/core/dev.c:7506
 napi_poll net/core/dev.c:7569 [inline]
 net_rx_action+0xa59/0x1ac0 net/core/dev.c:7696
 handle_softirqs+0x166/0x6e0 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x66/0x180 kernel/softirq.c:680
 irq_exit_rcu+0x12/0x20 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x84/0x90 arch/x86/kernel/apic/apic.c:1050
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:702

CPU: 0 UID: 0 PID: 16710 Comm: syz.6.3185 Tainted: G        W           syzkaller #0 PREEMPT(none) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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