=====================================================
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:6079 [inline]
 __netif_receive_skb+0x477/0xac0 net/core/dev.c:6192
 process_backlog+0x485/0xa00 net/core/dev.c:6544
 __napi_poll+0xdd/0x8a0 net/core/dev.c:7594
 napi_poll net/core/dev.c:7657 [inline]
 net_rx_action+0xbc8/0x1c30 net/core/dev.c:7784
 handle_softirqs+0x169/0x6e0 kernel/softirq.c:622
 __do_softirq+0x14/0x1b kernel/softirq.c:656
 do_softirq+0x99/0x100 kernel/softirq.c:523
 __local_bh_enable_ip+0xa1/0xb0 kernel/softirq.c:450
 __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:3744
 j1939_sk_sendmsg+0xeb/0x2760 net/can/j1939/socket.c:1285
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x333/0x3d0 net/socket.c:742
 ____sys_sendmsg+0x893/0xd80 net/socket.c:2630
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2684
 __sys_sendmmsg+0x2d9/0x7c0 net/socket.c:2773
 __do_sys_sendmmsg net/socket.c:2800 [inline]
 __se_sys_sendmmsg net/socket.c:2797 [inline]
 __x64_sys_sendmmsg+0xc6/0x150 net/socket.c:2797
 x64_sys_call+0x21de/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 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:4981 [inline]
 slab_alloc_node mm/slub.c:5284 [inline]
 __do_kmalloc_node mm/slub.c:5645 [inline]
 __kmalloc_node_track_caller_noprof+0xb4b/0x1ba0 mm/slub.c:5755
 kmalloc_reserve+0x22f/0x4b0 net/core/skbuff.c:601
 pskb_expand_head+0x1fc/0x1610 net/core/skbuff.c:2241
 netif_skb_check_for_xdp net/core/dev.c:5439 [inline]
 netif_receive_generic_xdp net/core/dev.c:5470 [inline]
 do_xdp_generic+0xa79/0x1690 net/core/dev.c:5538
 __netif_receive_skb_core+0x2bc2/0x7150 net/core/dev.c:5889
 __netif_receive_skb_one_core net/core/dev.c:6077 [inline]
 __netif_receive_skb+0xcc/0xac0 net/core/dev.c:6192
 process_backlog+0x485/0xa00 net/core/dev.c:6544
 __napi_poll+0xdd/0x8a0 net/core/dev.c:7594
 napi_poll net/core/dev.c:7657 [inline]
 net_rx_action+0xbc8/0x1c30 net/core/dev.c:7784
 handle_softirqs+0x169/0x6e0 kernel/softirq.c:622
 __do_softirq+0x14/0x1b kernel/softirq.c:656

CPU: 1 UID: 0 PID: 10145 Comm: syz.5.899 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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