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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+0x14/0x1b kernel/softirq.c:613
 do_softirq+0x99/0x100 kernel/softirq.c:480
 __local_bh_enable_ip+0xa1/0xb0 kernel/softirq.c:407
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
 _raw_spin_unlock_bh+0x2d/0x40 kernel/locking/spinlock.c:210
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 release_sock+0x21d/0x270 net/core/sock.c:3757
 j1939_sk_sendmsg+0xeb/0x2760 net/can/j1939/socket.c:1282
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x330/0x3d0 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+0x14/0x1b kernel/softirq.c:613

CPU: 1 UID: 0 PID: 15370 Comm: syz.4.2199 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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