syzbot

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BUG: KMSAN: uninit-value in bpf_prog_run_generic_xdp+0x10c4/0x1b90 net/core/dev.c:4767
 bpf_prog_run_generic_xdp+0x10c4/0x1b90 net/core/dev.c:4767
 netif_receive_generic_xdp net/core/dev.c:4830 [inline]
 do_xdp_generic+0x6e8/0xb90 net/core/dev.c:4889
 __netif_receive_skb_core+0x27a2/0x65a0 net/core/dev.c:5295
 __netif_receive_skb_one_core net/core/dev.c:5472 [inline]
 __netif_receive_skb+0xcd/0x5e0 net/core/dev.c:5588
 process_backlog+0x480/0x8b0 net/core/dev.c:5916
 __napi_poll+0xe4/0x950 net/core/dev.c:6477
 napi_poll net/core/dev.c:6544 [inline]
 net_rx_action+0x934/0x1a40 net/core/dev.c:6655
 __do_softirq+0x1c9/0x7c5 kernel/softirq.c:571
 run_ksoftirqd+0x30/0x50 kernel/softirq.c:934
 smpboot_thread_fn+0x558/0x9f0 kernel/smpboot.c:164
 kthread+0x31f/0x430 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

Uninit was stored to memory at:
 pskb_expand_head+0x328/0x19b0 net/core/skbuff.c:1907
 netif_receive_generic_xdp net/core/dev.c:4822 [inline]
 do_xdp_generic+0x56f/0xb90 net/core/dev.c:4889
 __netif_receive_skb_core+0x27a2/0x65a0 net/core/dev.c:5295
 __netif_receive_skb_one_core net/core/dev.c:5472 [inline]
 __netif_receive_skb+0xcd/0x5e0 net/core/dev.c:5588
 process_backlog+0x480/0x8b0 net/core/dev.c:5916
 __napi_poll+0xe4/0x950 net/core/dev.c:6477
 napi_poll net/core/dev.c:6544 [inline]
 net_rx_action+0x934/0x1a40 net/core/dev.c:6655
 __do_softirq+0x1c9/0x7c5 kernel/softirq.c:571

Uninit was created at:
 slab_post_alloc_hook+0x12d/0xb60 mm/slab.h:766
 slab_alloc_node mm/slub.c:3452 [inline]
 __kmem_cache_alloc_node+0x518/0x920 mm/slub.c:3491
 __do_kmalloc_node mm/slab_common.c:967 [inline]
 __kmalloc_node_track_caller+0x118/0x3c0 mm/slab_common.c:988
 kmalloc_reserve net/core/skbuff.c:492 [inline]
 __alloc_skb+0x3b8/0x900 net/core/skbuff.c:565
 alloc_skb include/linux/skbuff.h:1270 [inline]
 alloc_skb_with_frags+0xbd/0xbb0 net/core/skbuff.c:6194
 sock_alloc_send_pskb+0xaad/0xc30 net/core/sock.c:2743
 sock_alloc_send_skb include/net/sock.h:1888 [inline]
 j1939_sk_alloc_skb net/can/j1939/socket.c:864 [inline]
 j1939_sk_send_loop net/can/j1939/socket.c:1121 [inline]
 j1939_sk_sendmsg+0xd2e/0x25b0 net/can/j1939/socket.c:1256
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xa8f/0xe70 net/socket.c:2479
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2533
 __sys_sendmsg+0x25c/0x440 net/socket.c:2562
 __compat_sys_sendmsg net/compat.c:345 [inline]
 __do_compat_sys_sendmsg net/compat.c:352 [inline]
 __se_compat_sys_sendmsg net/compat.c:349 [inline]
 __ia32_compat_sys_sendmsg+0x9d/0xe0 net/compat.c:349
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

CPU: 0 PID: 13 Comm: ksoftirqd/0 Not tainted 6.2.0-syzkaller-81152-g97e36f4aa06f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023
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