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BUG: KMSAN: uninit-value in bpf_prog_run_generic_xdp+0x13a0/0x1ee0 net/core/dev.c:4882
 bpf_prog_run_generic_xdp+0x13a0/0x1ee0 net/core/dev.c:4882
 netif_receive_generic_xdp net/core/dev.c:4964 [inline]
 do_xdp_generic+0xb68/0x1440 net/core/dev.c:5023
 __netif_receive_skb_core+0x2533/0x6190 net/core/dev.c:5364
 __netif_receive_skb_one_core net/core/dev.c:5542 [inline]
 __netif_receive_skb+0xca/0xa00 net/core/dev.c:5658
 process_backlog+0x480/0x8b0 net/core/dev.c:5987
 __napi_poll+0xe7/0x980 net/core/dev.c:6638
 napi_poll net/core/dev.c:6707 [inline]
 net_rx_action+0x89d/0x1820 net/core/dev.c:6822
 __do_softirq+0x1c0/0x7d7 kernel/softirq.c:554
 do_softirq+0x9a/0x100 kernel/softirq.c:455
 __local_bh_enable_ip+0x9f/0xb0 kernel/softirq.c:382
 __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+0x219/0x250 net/core/sock.c:3559
 j1939_sk_sendmsg+0x23d8/0x2730 net/can/j1939/socket.c:1280
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x30f/0x380 net/socket.c:745
 ____sys_sendmsg+0x877/0xb60 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
 ia32_sys_call+0x209f/0x40a0 arch/x86/include/generated/asm/syscalls_32.h:371
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb4/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:411
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:449
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was stored to memory at:
 pskb_expand_head+0x30f/0x19d0 net/core/skbuff.c:2253
 netif_skb_check_for_xdp net/core/dev.c:4927 [inline]
 netif_receive_generic_xdp net/core/dev.c:4958 [inline]
 do_xdp_generic+0x931/0x1440 net/core/dev.c:5023
 __netif_receive_skb_core+0x2533/0x6190 net/core/dev.c:5364
 __netif_receive_skb_one_core net/core/dev.c:5542 [inline]
 __netif_receive_skb+0xca/0xa00 net/core/dev.c:5658
 process_backlog+0x480/0x8b0 net/core/dev.c:5987
 __napi_poll+0xe7/0x980 net/core/dev.c:6638
 napi_poll net/core/dev.c:6707 [inline]
 net_rx_action+0x89d/0x1820 net/core/dev.c:6822
 __do_softirq+0x1c0/0x7d7 kernel/softirq.c:554

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3804 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc_node+0x613/0xc50 mm/slub.c:3888
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:577
 __alloc_skb+0x35b/0x7a0 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1313 [inline]
 alloc_skb_with_frags+0xc8/0xbf0 net/core/skbuff.c:6504
 sock_alloc_send_pskb+0xa81/0xbf0 net/core/sock.c:2795
 sock_alloc_send_skb include/net/sock.h:1842 [inline]
 j1939_sk_alloc_skb net/can/j1939/socket.c:878 [inline]
 j1939_sk_send_loop net/can/j1939/socket.c:1142 [inline]
 j1939_sk_sendmsg+0xc0a/0x2730 net/can/j1939/socket.c:1277
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg+0x30f/0x380 net/socket.c:745
 ____sys_sendmsg+0x877/0xb60 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
 ia32_sys_call+0x209f/0x40a0 arch/x86/include/generated/asm/syscalls_32.h:371
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb4/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:411
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:449
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

CPU: 0 PID: 15504 Comm: syz-executor.0 Not tainted 6.9.0-rc5-syzkaller-00007-g4d2008430ce8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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