syzbot

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BUG: KMSAN: uninit-value in __vlan_get_protocol include/linux/if_vlan.h:602 [inline]
BUG: KMSAN: uninit-value in vlan_parse_protocol+0xe8/0x4e0 net/8021q/vlan_dev.c:511
 __vlan_get_protocol include/linux/if_vlan.h:602 [inline]
 vlan_parse_protocol+0xe8/0x4e0 net/8021q/vlan_dev.c:511
 dev_parse_header_protocol include/linux/netdevice.h:3167 [inline]
 packet_parse_headers+0x205/0xc80 net/packet/af_packet.c:1996
 packet_snd net/packet/af_packet.c:3135 [inline]
 packet_sendmsg+0x8df3/0xa370 net/packet/af_packet.c:3177
 sock_sendmsg_nosec net/socket.c:729 [inline]
 __sock_sendmsg+0x30f/0x380 net/socket.c:744
 __sys_sendto+0x645/0x7f0 net/socket.c:2214
 __do_sys_sendto net/socket.c:2226 [inline]
 __se_sys_sendto net/socket.c:2222 [inline]
 __ia32_sys_sendto+0x123/0x1c0 net/socket.c:2222
 ia32_sys_call+0xb2/0x40d0 arch/x86/include/generated/asm/syscalls_32.h:370
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb0/0x110 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 created at:
 slab_post_alloc_hook mm/slub.c:4091 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 kmem_cache_alloc_node_noprof+0x6bf/0xb80 mm/slub.c:4186
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:587
 __alloc_skb+0x363/0x7b0 net/core/skbuff.c:678
 alloc_skb include/linux/skbuff.h:1322 [inline]
 alloc_skb_with_frags+0xc8/0xd00 net/core/skbuff.c:6612
 sock_alloc_send_pskb+0xa81/0xbf0 net/core/sock.c:2883
 packet_alloc_skb net/packet/af_packet.c:2994 [inline]
 packet_snd net/packet/af_packet.c:3088 [inline]
 packet_sendmsg+0x7319/0xa370 net/packet/af_packet.c:3177
 sock_sendmsg_nosec net/socket.c:729 [inline]
 __sock_sendmsg+0x30f/0x380 net/socket.c:744
 __sys_sendto+0x645/0x7f0 net/socket.c:2214
 __do_sys_sendto net/socket.c:2226 [inline]
 __se_sys_sendto net/socket.c:2222 [inline]
 __ia32_sys_sendto+0x123/0x1c0 net/socket.c:2222
 ia32_sys_call+0xb2/0x40d0 arch/x86/include/generated/asm/syscalls_32.h:370
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb0/0x110 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 UID: 0 PID: 7067 Comm: syz.0.632 Tainted: G        W          6.12.0-rc4-syzkaller #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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