===================================================== 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: 0 PID: 12436 Comm: syz-executor.3 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 dev_queue_xmit_nit+0x11a0/0x1280 net/core/dev.c:2355 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 neigh_resolve_output+0xab0/0xb40 net/core/neighbour.c:1489 neigh_output include/net/neighbour.h:509 [inline] ip6_finish_output2+0x20fb/0x2620 net/ipv6/ip6_output.c:117 __ip6_finish_output+0x824/0x8e0 net/ipv6/ip6_output.c:143 ip6_finish_output+0x166/0x410 net/ipv6/ip6_output.c:153 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x60a/0x770 net/ipv6/ip6_output.c:176 dst_output include/net/dst.h:443 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip6_xmit+0x1f67/0x2710 net/ipv6/ip6_output.c:280 inet6_csk_xmit+0x42b/0x570 net/ipv6/inet6_connection_sock.c:135 __tcp_transmit_skb+0x440e/0x6090 net/ipv4/tcp_output.c:1240 tcp_transmit_skb net/ipv4/tcp_output.c:1256 [inline] tcp_send_syn_data net/ipv4/tcp_output.c:3633 [inline] tcp_connect+0x5a94/0x6830 net/ipv4/tcp_output.c:3672 tcp_v6_connect+0x259c/0x2780 net/ipv6/tcp_ipv6.c:334 __inet_stream_connect+0x2fb/0x1340 net/ipv4/af_inet.c:658 tcp_sendmsg_fastopen net/ipv4/tcp.c:1172 [inline] tcp_sendmsg_locked+0x6714/0x6d00 net/ipv4/tcp.c:1214 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1441 inet6_sendmsg+0x178/0x2e0 net/ipv6/af_inet6.c:638 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] __sys_sendto+0x90c/0xc90 net/socket.c:1995 __do_sys_sendto net/socket.c:2007 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:2003 __x64_sys_sendto+0x6e/0x90 net/socket.c:2003 do_syscall_64+0xb0/0x150 arch/x86/entry/common.c:386 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45c1d9 Code: Bad RIP value. RSP: 002b:00007f302a08fc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000000000002b200 RCX: 000000000045c1d9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000078bf58 R08: 0000000020000280 R09: 000000000000001c R10: 0000000020000004 R11: 0000000000000246 R12: 000000000078bf0c R13: 0000000000c9fb6f R14: 00007f302a0909c0 R15: 000000000078bf0c 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 dev_queue_xmit_nit+0x11a0/0x1280 net/core/dev.c:2355 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 neigh_resolve_output+0xab0/0xb40 net/core/neighbour.c:1489 neigh_output include/net/neighbour.h:509 [inline] ip6_finish_output2+0x20fb/0x2620 net/ipv6/ip6_output.c:117 __ip6_finish_output+0x824/0x8e0 net/ipv6/ip6_output.c:143 ip6_finish_output+0x166/0x410 net/ipv6/ip6_output.c:153 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x60a/0x770 net/ipv6/ip6_output.c:176 dst_output include/net/dst.h:443 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip6_xmit+0x1f67/0x2710 net/ipv6/ip6_output.c:280 inet6_csk_xmit+0x42b/0x570 net/ipv6/inet6_connection_sock.c:135 __tcp_transmit_skb+0x440e/0x6090 net/ipv4/tcp_output.c:1240 tcp_transmit_skb net/ipv4/tcp_output.c:1256 [inline] tcp_send_syn_data net/ipv4/tcp_output.c:3633 [inline] tcp_connect+0x5a94/0x6830 net/ipv4/tcp_output.c:3672 tcp_v6_connect+0x259c/0x2780 net/ipv6/tcp_ipv6.c:334 __inet_stream_connect+0x2fb/0x1340 net/ipv4/af_inet.c:658 tcp_sendmsg_fastopen net/ipv4/tcp.c:1172 [inline] tcp_sendmsg_locked+0x6714/0x6d00 net/ipv4/tcp.c:1214 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1441 inet6_sendmsg+0x178/0x2e0 net/ipv6/af_inet6.c:638 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] __sys_sendto+0x90c/0xc90 net/socket.c:1995 __do_sys_sendto net/socket.c:2007 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:2003 __x64_sys_sendto+0x6e/0x90 net/socket.c:2003 do_syscall_64+0xb0/0x150 arch/x86/entry/common.c:386 entry_SYSCALL_64_after_hwframe+0x44/0xa9 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 dev_queue_xmit_nit+0x11a0/0x1280 net/core/dev.c:2355 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 neigh_resolve_output+0xab0/0xb40 net/core/neighbour.c:1489 neigh_output include/net/neighbour.h:509 [inline] ip6_finish_output2+0x20fb/0x2620 net/ipv6/ip6_output.c:117 __ip6_finish_output+0x824/0x8e0 net/ipv6/ip6_output.c:143 ip6_finish_output+0x166/0x410 net/ipv6/ip6_output.c:153 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x60a/0x770 net/ipv6/ip6_output.c:176 dst_output include/net/dst.h:443 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ip6_xmit+0x1f67/0x2710 net/ipv6/ip6_output.c:280 inet6_csk_xmit+0x42b/0x570 net/ipv6/inet6_connection_sock.c:135 __tcp_transmit_skb+0x440e/0x6090 net/ipv4/tcp_output.c:1240 tcp_transmit_skb net/ipv4/tcp_output.c:1256 [inline] tcp_send_syn_data net/ipv4/tcp_output.c:3633 [inline] tcp_connect+0x5a94/0x6830 net/ipv4/tcp_output.c:3672 tcp_v6_connect+0x259c/0x2780 net/ipv6/tcp_ipv6.c:334 __inet_stream_connect+0x2fb/0x1340 net/ipv4/af_inet.c:658 tcp_sendmsg_fastopen net/ipv4/tcp.c:1172 [inline] tcp_sendmsg_locked+0x6714/0x6d00 net/ipv4/tcp.c:1214 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1441 inet6_sendmsg+0x178/0x2e0 net/ipv6/af_inet6.c:638 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] __sys_sendto+0x90c/0xc90 net/socket.c:1995 __do_sys_sendto net/socket.c:2007 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:2003 __x64_sys_sendto+0x6e/0x90 net/socket.c:2003 do_syscall_64+0xb0/0x150 arch/x86/entry/common.c:386 entry_SYSCALL_64_after_hwframe+0x44/0xa9 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 =====================================================