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BUG: KMSAN: uninit-value in bpf_prog_run_generic_xdp+0x1064/0x1a90 net/core/dev.c:4887
 bpf_prog_run_generic_xdp+0x1064/0x1a90 net/core/dev.c:4887
 netif_receive_generic_xdp net/core/dev.c:4950 [inline]
 do_xdp_generic+0x681/0xaf0 net/core/dev.c:5009
 __netif_receive_skb_core+0x251a/0x6100 net/core/dev.c:5350
 __netif_receive_skb_one_core net/core/dev.c:5527 [inline]
 __netif_receive_skb+0xc3/0x5a0 net/core/dev.c:5643
 process_backlog+0x480/0x8b0 net/core/dev.c:5971
 __napi_poll+0xe3/0x970 net/core/dev.c:6533
 napi_poll net/core/dev.c:6602 [inline]
 net_rx_action+0x884/0x16d0 net/core/dev.c:6735
 __do_softirq+0x1b7/0x7c3 kernel/softirq.c:553
 do_softirq+0x9a/0xf0 kernel/softirq.c:454
 __local_bh_enable_ip+0x99/0xa0 kernel/softirq.c:381
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
 _raw_spin_unlock_bh+0x2d/0x30 kernel/locking/spinlock.c:210
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 release_sock+0x1e5/0x200 net/core/sock.c:3543
 j1939_sk_sendmsg+0x2322/0x2570 net/can/j1939/socket.c:1266
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmsg+0x225/0x3c0 net/socket.c:2667
 __compat_sys_sendmsg net/compat.c:346 [inline]
 __do_compat_sys_sendmsg net/compat.c:353 [inline]
 __se_compat_sys_sendmsg net/compat.c:350 [inline]
 __ia32_compat_sys_sendmsg+0x9d/0xe0 net/compat.c:350
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:321
 do_fast_syscall_32+0x37/0x70 arch/x86/entry/common.c:346
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:384
 entry_SYSENTER_compat_after_hwframe+0x70/0x7a

Uninit was stored to memory at:
 pskb_expand_head+0x305/0x1a00 net/core/skbuff.c:2106
 netif_receive_generic_xdp net/core/dev.c:4942 [inline]
 do_xdp_generic+0x511/0xaf0 net/core/dev.c:5009
 __netif_receive_skb_core+0x251a/0x6100 net/core/dev.c:5350
 __netif_receive_skb_one_core net/core/dev.c:5527 [inline]
 __netif_receive_skb+0xc3/0x5a0 net/core/dev.c:5643
 process_backlog+0x480/0x8b0 net/core/dev.c:5971
 __napi_poll+0xe3/0x970 net/core/dev.c:6533
 napi_poll net/core/dev.c:6602 [inline]
 net_rx_action+0x884/0x16d0 net/core/dev.c:6735
 __do_softirq+0x1b7/0x7c3 kernel/softirq.c:553

Uninit was created at:
 slab_post_alloc_hook+0x129/0xa70 mm/slab.h:768
 slab_alloc_node mm/slub.c:3478 [inline]
 kmem_cache_alloc_node+0x5e9/0xb10 mm/slub.c:3523
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:560
 __alloc_skb+0x318/0x740 net/core/skbuff.c:651
 alloc_skb include/linux/skbuff.h:1286 [inline]
 alloc_skb_with_frags+0xc8/0xbd0 net/core/skbuff.c:6332
 sock_alloc_send_pskb+0xa80/0xbf0 net/core/sock.c:2780
 sock_alloc_send_skb include/net/sock.h:1884 [inline]
 j1939_sk_alloc_skb net/can/j1939/socket.c:864 [inline]
 j1939_sk_send_loop net/can/j1939/socket.c:1128 [inline]
 j1939_sk_sendmsg+0xd18/0x2570 net/can/j1939/socket.c:1263
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmsg+0x225/0x3c0 net/socket.c:2667
 __compat_sys_sendmsg net/compat.c:346 [inline]
 __do_compat_sys_sendmsg net/compat.c:353 [inline]
 __se_compat_sys_sendmsg net/compat.c:350 [inline]
 __ia32_compat_sys_sendmsg+0x9d/0xe0 net/compat.c:350
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:321
 do_fast_syscall_32+0x37/0x70 arch/x86/entry/common.c:346
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:384
 entry_SYSENTER_compat_after_hwframe+0x70/0x7a

CPU: 0 PID: 13082 Comm: syz-executor.5 Not tainted 6.7.0-rc5-syzkaller-00200-g3bd7d7488169 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
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