syzbot

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BUG: KMSAN: uninit-value in __skb_flow_dissect+0x426a/0x9ed0 net/core/flow_dissector.c:1204
 __skb_flow_dissect+0x426a/0x9ed0 net/core/flow_dissector.c:1204
 skb_flow_dissect_flow_keys_basic include/linux/skbuff.h:1624 [inline]
 skb_probe_transport_header include/linux/skbuff.h:3180 [inline]
 packet_parse_headers+0xc9e/0xed0 net/packet/af_packet.c:1938
 packet_snd net/packet/af_packet.c:3066 [inline]
 packet_sendmsg+0x8aed/0xa2a0 net/packet/af_packet.c:3108
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x333/0x3d0 net/socket.c:742
 ____sys_sendmsg+0x893/0xd80 net/socket.c:2630
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2684
 __sys_sendmmsg+0x2d9/0x7c0 net/socket.c:2773
 __do_sys_sendmmsg net/socket.c:2800 [inline]
 __se_sys_sendmmsg net/socket.c:2797 [inline]
 __x64_sys_sendmmsg+0xc6/0x150 net/socket.c:2797
 x64_sys_call+0x21de/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4962 [inline]
 slab_alloc_node mm/slub.c:5265 [inline]
 kmem_cache_alloc_node_noprof+0x989/0x16b0 mm/slub.c:5317
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:579
 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:670
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xc5/0xa60 net/core/skbuff.c:6671
 sock_alloc_send_pskb+0xacc/0xc60 net/core/sock.c:2965
 packet_alloc_skb net/packet/af_packet.c:2926 [inline]
 packet_snd net/packet/af_packet.c:3019 [inline]
 packet_sendmsg+0x743d/0xa2a0 net/packet/af_packet.c:3108
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x333/0x3d0 net/socket.c:742
 ____sys_sendmsg+0x893/0xd80 net/socket.c:2630
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2684
 __sys_sendmmsg+0x2d9/0x7c0 net/socket.c:2773
 __do_sys_sendmmsg net/socket.c:2800 [inline]
 __se_sys_sendmmsg net/socket.c:2797 [inline]
 __x64_sys_sendmmsg+0xc6/0x150 net/socket.c:2797
 x64_sys_call+0x21de/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 13143 Comm: syz.1.2131 Tainted: G        W           syzkaller #0 PREEMPT(none) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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