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BUG: KMSAN: uninit-value in bpf_prog_run_generic_xdp+0x16ee/0x20e0 net/core/dev.c:4757
 bpf_prog_run_generic_xdp+0x16ee/0x20e0 net/core/dev.c:4757
 netif_receive_generic_xdp+0x862/0xb00 net/core/dev.c:4820
 do_xdp_generic net/core/dev.c:4875 [inline]
 __netif_receive_skb_core+0x2bc0/0x5e80 net/core/dev.c:5283
 __netif_receive_skb_one_core net/core/dev.c:5460 [inline]
 __netif_receive_skb+0xf2/0x630 net/core/dev.c:5576
 process_backlog+0x562/0xc30 net/core/dev.c:6452
 __napi_poll+0x14e/0xbc0 net/core/dev.c:7020
 napi_poll net/core/dev.c:7087 [inline]
 net_rx_action+0x824/0x1880 net/core/dev.c:7174
 __do_softirq+0x1fe/0x7eb kernel/softirq.c:558
 run_ksoftirqd+0x33/0x50 kernel/softirq.c:920
 smpboot_thread_fn+0x616/0xbf0 kernel/smpboot.c:164
 kthread+0x721/0x850 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30

Uninit was stored to memory at:
 pskb_expand_head+0x3cb/0x1db0 net/core/skbuff.c:1710
 netif_receive_generic_xdp+0x5f0/0xb00 net/core/dev.c:4812
 do_xdp_generic net/core/dev.c:4875 [inline]
 __netif_receive_skb_core+0x2bc0/0x5e80 net/core/dev.c:5283
 __netif_receive_skb_one_core net/core/dev.c:5460 [inline]
 __netif_receive_skb+0xf2/0x630 net/core/dev.c:5576
 process_backlog+0x562/0xc30 net/core/dev.c:6452
 __napi_poll+0x14e/0xbc0 net/core/dev.c:7020
 napi_poll net/core/dev.c:7087 [inline]
 net_rx_action+0x824/0x1880 net/core/dev.c:7174
 __do_softirq+0x1fe/0x7eb kernel/softirq.c:558

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:524 [inline]
 slab_alloc_node mm/slub.c:3251 [inline]
 __kmalloc_node_track_caller+0xe0c/0x1510 mm/slub.c:4974
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 __alloc_skb+0x545/0xf90 net/core/skbuff.c:426
 alloc_skb include/linux/skbuff.h:1126 [inline]
 alloc_skb_with_frags+0x1dc/0xc10 net/core/skbuff.c:6078
 sock_alloc_send_pskb+0xe37/0x1010 net/core/sock.c:2575
 sock_alloc_send_skb+0xca/0xe0 net/core/sock.c:2592
 j1939_sk_alloc_skb net/can/j1939/socket.c:861 [inline]
 j1939_sk_send_loop net/can/j1939/socket.c:1118 [inline]
 j1939_sk_sendmsg+0xf7b/0x2910 net/can/j1939/socket.c:1253
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg net/socket.c:724 [inline]
 ____sys_sendmsg+0xe11/0x12c0 net/socket.c:2409
 ___sys_sendmsg net/socket.c:2463 [inline]
 __sys_sendmsg+0x4a5/0x640 net/socket.c:2492
 __compat_sys_sendmsg net/compat.c:347 [inline]
 __do_compat_sys_sendmsg net/compat.c:354 [inline]
 __se_compat_sys_sendmsg net/compat.c:351 [inline]
 __ia32_compat_sys_sendmsg+0xed/0x130 net/compat.c:351
 do_syscall_32_irqs_on arch/x86/entry/common.c:114 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:180
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:205
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:248
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

CPU: 1 PID: 18 Comm: ksoftirqd/1 Not tainted 5.16.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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