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BUG: KMSAN: uninit-value in ____bpf_skb_get_nlattr net/core/filter.c:144 [inline]
BUG: KMSAN: uninit-value in bpf_skb_get_nlattr+0x145/0x290 net/core/filter.c:134
CPU: 1 PID: 22460 Comm: syz-executor.2 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1df/0x240 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 ____bpf_skb_get_nlattr net/core/filter.c:144 [inline]
 bpf_skb_get_nlattr+0x145/0x290 net/core/filter.c:134
 ___bpf_prog_run+0x214d/0x97a0 kernel/bpf/core.c:1516
 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681
 bpf_dispatcher_nop_func include/linux/bpf.h:556 [inline]
 bpf_prog_run_pin_on_cpu include/linux/filter.h:597 [inline]
 bpf_prog_run_clear_cb include/linux/filter.h:719 [inline]
 run_filter net/packet/af_packet.c:2012 [inline]
 packet_rcv+0x70f/0x2150 net/packet/af_packet.c:2085
 deliver_skb net/core/dev.c:2247 [inline]
 dev_queue_xmit_nit+0x862/0x1280 net/core/dev.c:2317
 xmit_one net/core/dev.c:3552 [inline]
 dev_hard_start_xmit+0x20c/0xa70 net/core/dev.c:3572
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4131
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
 packet_snd net/packet/af_packet.c:2979 [inline]
 packet_sendmsg+0x763f/0x87a0 net/packet/af_packet.c:3004
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 __sys_sendto+0xc56/0xc90 net/socket.c:1995
 __do_sys_sendto net/socket.c:2007 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:2003
 __ia32_sys_sendto+0x6e/0x90 net/socket.c:2003
 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline]
 __do_fast_syscall_32+0x2aa/0x400 arch/x86/entry/common.c:477
 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7fdb549
Code: Bad RIP value.
RSP: 002b:00000000f5dd60cc EFLAGS: 00000296 ORIG_RAX: 0000000000000171
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000300
RDX: 000000000000fdfa RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165
 ___bpf_prog_run+0x6cbe/0x97a0 kernel/bpf/core.c:1391
 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681
 bpf_dispatcher_nop_func include/linux/bpf.h:556 [inline]
 bpf_prog_run_pin_on_cpu include/linux/filter.h:597 [inline]
 bpf_prog_run_clear_cb include/linux/filter.h:719 [inline]
 run_filter net/packet/af_packet.c:2012 [inline]
 packet_rcv+0x70f/0x2150 net/packet/af_packet.c:2085
 deliver_skb net/core/dev.c:2247 [inline]
 dev_queue_xmit_nit+0x862/0x1280 net/core/dev.c:2317
 xmit_one net/core/dev.c:3552 [inline]
 dev_hard_start_xmit+0x20c/0xa70 net/core/dev.c:3572
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4131
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
 packet_snd net/packet/af_packet.c:2979 [inline]
 packet_sendmsg+0x763f/0x87a0 net/packet/af_packet.c:3004
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 __sys_sendto+0xc56/0xc90 net/socket.c:1995
 __do_sys_sendto net/socket.c:2007 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:2003
 __ia32_sys_sendto+0x6e/0x90 net/socket.c:2003
 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline]
 __do_fast_syscall_32+0x2aa/0x400 arch/x86/entry/common.c:477
 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165
 ___bpf_prog_run+0x6c64/0x97a0 kernel/bpf/core.c:1391
 __bpf_prog_run32+0x101/0x170 kernel/bpf/core.c:1681
 bpf_dispatcher_nop_func include/linux/bpf.h:556 [inline]
 bpf_prog_run_pin_on_cpu include/linux/filter.h:597 [inline]
 bpf_prog_run_clear_cb include/linux/filter.h:719 [inline]
 run_filter net/packet/af_packet.c:2012 [inline]
 packet_rcv+0x70f/0x2150 net/packet/af_packet.c:2085
 deliver_skb net/core/dev.c:2247 [inline]
 dev_queue_xmit_nit+0x862/0x1280 net/core/dev.c:2317
 xmit_one net/core/dev.c:3552 [inline]
 dev_hard_start_xmit+0x20c/0xa70 net/core/dev.c:3572
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4131
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
 packet_snd net/packet/af_packet.c:2979 [inline]
 packet_sendmsg+0x763f/0x87a0 net/packet/af_packet.c:3004
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 __sys_sendto+0xc56/0xc90 net/socket.c:1995
 __do_sys_sendto net/socket.c:2007 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:2003
 __ia32_sys_sendto+0x6e/0x90 net/socket.c:2003
 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline]
 __do_fast_syscall_32+0x2aa/0x400 arch/x86/entry/common.c:477
 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Local variable ----regs@__bpf_prog_run32 created at:
 __bpf_prog_run32+0x87/0x170 kernel/bpf/core.c:1681
 __bpf_prog_run32+0x87/0x170 kernel/bpf/core.c:1681
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