===================================================== BUG: KMSAN: uninit-value in ____bpf_skb_load_helper_32 net/core/filter.c:238 [inline] BUG: KMSAN: uninit-value in bpf_skb_load_helper_32+0xee/0x2d0 net/core/filter.c:232 CPU: 0 PID: 22856 Comm: syz-executor.5 Not tainted 5.7.0-rc4-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+0x1c9/0x220 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_load_helper_32 net/core/filter.c:238 [inline] bpf_skb_load_helper_32+0xee/0x2d0 net/core/filter.c:232 ___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:545 [inline] __bpf_prog_run_save_cb include/linux/filter.h:693 [inline] bpf_prog_run_save_cb include/linux/filter.h:707 [inline] sk_filter_trim_cap+0x42a/0xcc0 net/core/filter.c:119 sk_filter include/linux/filter.h:833 [inline] sock_queue_rcv_skb+0x83/0x130 net/core/sock.c:487 packet_rcv_spkt+0x656/0x7c0 net/packet/af_packet.c:1851 dev_queue_xmit_nit+0x1199/0x1270 net/core/dev.c:2276 xmit_one net/core/dev.c:3473 [inline] dev_hard_start_xmit+0x20f/0xab0 net/core/dev.c:3493 sch_direct_xmit+0x512/0x18b0 net/sched/sch_generic.c:314 qdisc_restart net/sched/sch_generic.c:377 [inline] __qdisc_run+0x15ec/0x3350 net/sched/sch_generic.c:385 qdisc_run include/net/pkt_sched.h:134 [inline] __dev_xmit_skb net/core/dev.c:3668 [inline] __dev_queue_xmit+0x23b7/0x3b20 net/core/dev.c:4021 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4085 neigh_hh_output include/net/neighbour.h:499 [inline] neigh_output include/net/neighbour.h:508 [inline] ip_finish_output2+0x20fd/0x2610 net/ipv4/ip_output.c:228 ip_do_fragment+0x2c98/0x3570 net/ipv4/ip_output.c:849 ip_fragment+0x242/0x400 net/ipv4/ip_output.c:585 __ip_finish_output+0xd34/0xd80 net/ipv4/ip_output.c:304 ip_finish_output+0x166/0x410 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip_mc_output+0xfbf/0x1090 net/ipv4/ip_output.c:415 dst_output include/net/dst.h:435 [inline] ip_local_out net/ipv4/ip_output.c:125 [inline] ip_send_skb+0x179/0x360 net/ipv4/ip_output.c:1560 udp_send_skb+0x1046/0x18b0 net/ipv4/udp.c:891 udp_push_pending_frames net/ipv4/udp.c:919 [inline] udp_sendpage+0x7e2/0xac0 net/ipv4/udp.c:1290 inet_sendpage+0x1ab/0x2c0 net/ipv4/af_inet.c:821 kernel_sendpage net/socket.c:3808 [inline] sock_sendpage+0x1e1/0x2c0 net/socket.c:950 pipe_to_sendpage+0x38c/0x4c0 fs/splice.c:458 splice_from_pipe_feed fs/splice.c:512 [inline] __splice_from_pipe+0x539/0xed0 fs/splice.c:636 splice_from_pipe fs/splice.c:671 [inline] generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:844 do_splice_from fs/splice.c:863 [inline] do_splice+0x1eae/0x2ec0 fs/splice.c:1170 __do_sys_splice fs/splice.c:1447 [inline] __se_sys_splice+0x426/0x520 fs/splice.c:1427 __x64_sys_splice+0x6e/0x90 fs/splice.c:1427 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45ca29 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2c3e0b3c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 00000000005079c0 RCX: 000000000045ca29 RDX: 0000000000000005 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000078bfa0 R08: 0000000000030005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000bae R14: 00000000004ce9f7 R15: 00007f2c3e0b46d4 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:545 [inline] __bpf_prog_run_save_cb include/linux/filter.h:693 [inline] bpf_prog_run_save_cb include/linux/filter.h:707 [inline] sk_filter_trim_cap+0x42a/0xcc0 net/core/filter.c:119 sk_filter include/linux/filter.h:833 [inline] sock_queue_rcv_skb+0x83/0x130 net/core/sock.c:487 packet_rcv_spkt+0x656/0x7c0 net/packet/af_packet.c:1851 dev_queue_xmit_nit+0x1199/0x1270 net/core/dev.c:2276 xmit_one net/core/dev.c:3473 [inline] dev_hard_start_xmit+0x20f/0xab0 net/core/dev.c:3493 sch_direct_xmit+0x512/0x18b0 net/sched/sch_generic.c:314 qdisc_restart net/sched/sch_generic.c:377 [inline] __qdisc_run+0x15ec/0x3350 net/sched/sch_generic.c:385 qdisc_run include/net/pkt_sched.h:134 [inline] __dev_xmit_skb net/core/dev.c:3668 [inline] __dev_queue_xmit+0x23b7/0x3b20 net/core/dev.c:4021 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4085 neigh_hh_output include/net/neighbour.h:499 [inline] neigh_output include/net/neighbour.h:508 [inline] ip_finish_output2+0x20fd/0x2610 net/ipv4/ip_output.c:228 ip_do_fragment+0x2c98/0x3570 net/ipv4/ip_output.c:849 ip_fragment+0x242/0x400 net/ipv4/ip_output.c:585 __ip_finish_output+0xd34/0xd80 net/ipv4/ip_output.c:304 ip_finish_output+0x166/0x410 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip_mc_output+0xfbf/0x1090 net/ipv4/ip_output.c:415 dst_output include/net/dst.h:435 [inline] ip_local_out net/ipv4/ip_output.c:125 [inline] ip_send_skb+0x179/0x360 net/ipv4/ip_output.c:1560 udp_send_skb+0x1046/0x18b0 net/ipv4/udp.c:891 udp_push_pending_frames net/ipv4/udp.c:919 [inline] udp_sendpage+0x7e2/0xac0 net/ipv4/udp.c:1290 inet_sendpage+0x1ab/0x2c0 net/ipv4/af_inet.c:821 kernel_sendpage net/socket.c:3808 [inline] sock_sendpage+0x1e1/0x2c0 net/socket.c:950 pipe_to_sendpage+0x38c/0x4c0 fs/splice.c:458 splice_from_pipe_feed fs/splice.c:512 [inline] __splice_from_pipe+0x539/0xed0 fs/splice.c:636 splice_from_pipe fs/splice.c:671 [inline] generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:844 do_splice_from fs/splice.c:863 [inline] do_splice+0x1eae/0x2ec0 fs/splice.c:1170 __do_sys_splice fs/splice.c:1447 [inline] __se_sys_splice+0x426/0x520 fs/splice.c:1427 __x64_sys_splice+0x6e/0x90 fs/splice.c:1427 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:297 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:545 [inline] __bpf_prog_run_save_cb include/linux/filter.h:693 [inline] bpf_prog_run_save_cb include/linux/filter.h:707 [inline] sk_filter_trim_cap+0x42a/0xcc0 net/core/filter.c:119 sk_filter include/linux/filter.h:833 [inline] sock_queue_rcv_skb+0x83/0x130 net/core/sock.c:487 packet_rcv_spkt+0x656/0x7c0 net/packet/af_packet.c:1851 dev_queue_xmit_nit+0x1199/0x1270 net/core/dev.c:2276 xmit_one net/core/dev.c:3473 [inline] dev_hard_start_xmit+0x20f/0xab0 net/core/dev.c:3493 sch_direct_xmit+0x512/0x18b0 net/sched/sch_generic.c:314 qdisc_restart net/sched/sch_generic.c:377 [inline] __qdisc_run+0x15ec/0x3350 net/sched/sch_generic.c:385 qdisc_run include/net/pkt_sched.h:134 [inline] __dev_xmit_skb net/core/dev.c:3668 [inline] __dev_queue_xmit+0x23b7/0x3b20 net/core/dev.c:4021 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4085 neigh_hh_output include/net/neighbour.h:499 [inline] neigh_output include/net/neighbour.h:508 [inline] ip_finish_output2+0x20fd/0x2610 net/ipv4/ip_output.c:228 ip_do_fragment+0x2c98/0x3570 net/ipv4/ip_output.c:849 ip_fragment+0x242/0x400 net/ipv4/ip_output.c:585 __ip_finish_output+0xd34/0xd80 net/ipv4/ip_output.c:304 ip_finish_output+0x166/0x410 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip_mc_output+0xfbf/0x1090 net/ipv4/ip_output.c:415 dst_output include/net/dst.h:435 [inline] ip_local_out net/ipv4/ip_output.c:125 [inline] ip_send_skb+0x179/0x360 net/ipv4/ip_output.c:1560 udp_send_skb+0x1046/0x18b0 net/ipv4/udp.c:891 udp_push_pending_frames net/ipv4/udp.c:919 [inline] udp_sendpage+0x7e2/0xac0 net/ipv4/udp.c:1290 inet_sendpage+0x1ab/0x2c0 net/ipv4/af_inet.c:821 kernel_sendpage net/socket.c:3808 [inline] sock_sendpage+0x1e1/0x2c0 net/socket.c:950 pipe_to_sendpage+0x38c/0x4c0 fs/splice.c:458 splice_from_pipe_feed fs/splice.c:512 [inline] __splice_from_pipe+0x539/0xed0 fs/splice.c:636 splice_from_pipe fs/splice.c:671 [inline] generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:844 do_splice_from fs/splice.c:863 [inline] do_splice+0x1eae/0x2ec0 fs/splice.c:1170 __do_sys_splice fs/splice.c:1447 [inline] __se_sys_splice+0x426/0x520 fs/splice.c:1427 __x64_sys_splice+0x6e/0x90 fs/splice.c:1427 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:297 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 =====================================================