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KMSAN: uninit-value in packet_rcv_fanout

Status: closed as invalid on 2020/05/28 10:23
Subsystems: net
[Documentation on labels]
First crash: 1431d, last: 1430d
▶ ▼ Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: uninit-value in packet_rcv_fanout (2) net C 11 1376d 1379d 0/26 closed as invalid on 2020/07/22 14:22

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in packet_rcv_fanout+0x2442/0x25c0 net/packet/af_packet.c:1463
CPU: 0 PID: 8783 Comm: sshd 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
 packet_rcv_fanout+0x2442/0x25c0 net/packet/af_packet.c:1463
 deliver_skb net/core/dev.c:2168 [inline]
 dev_queue_xmit_nit+0x862/0x1270 net/core/dev.c:2238
 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_finish_output+0xaa7/0xd80 net/ipv4/ip_output.c:306
 ip_finish_output+0x166/0x410 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0x593/0x680 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:435 [inline]
 ip_local_out net/ipv4/ip_output.c:125 [inline]
 __ip_queue_xmit+0x1b5c/0x21a0 net/ipv4/ip_output.c:530
 ip_queue_xmit+0xcc/0xf0 include/net/ip.h:237
 __tcp_transmit_skb+0x4221/0x6090 net/ipv4/tcp_output.c:1238
 tcp_transmit_skb net/ipv4/tcp_output.c:1254 [inline]
 tcp_write_xmit+0x30e1/0xb470 net/ipv4/tcp_output.c:2517
 __tcp_push_pending_frames+0x124/0x4e0 net/ipv4/tcp_output.c:2693
 tcp_push+0x6fa/0x8a0 net/ipv4/tcp.c:725
 tcp_sendmsg_locked+0x5d89/0x6d00 net/ipv4/tcp.c:1403
 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1433
 inet_sendmsg+0x178/0x2e0 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 sock_write_iter+0x606/0x6d0 net/socket.c:1004
 call_write_iter include/linux/fs.h:1907 [inline]
 new_sync_write fs/read_write.c:484 [inline]
 __vfs_write+0xa5a/0xca0 fs/read_write.c:497
 vfs_write+0x444/0x8e0 fs/read_write.c:559
 ksys_write+0x267/0x450 fs/read_write.c:612
 __do_sys_write fs/read_write.c:624 [inline]
 __se_sys_write+0x92/0xb0 fs/read_write.c:621
 __x64_sys_write+0x4a/0x70 fs/read_write.c:621
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7faec4a14970
Code: 73 01 c3 48 8b 0d 28 d5 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 99 2d 2c 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 7e 9b 01 00 48 89 04 24
RSP: 002b:00007ffcb608a808 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000034 RCX: 00007faec4a14970
RDX: 0000000000000034 RSI: 0000556540a3cdd8 RDI: 0000000000000003
RBP: 0000556540a2e0f0 R08: 00007ffcb60bd080 R09: 0000000000000070
R10: 000000000000009f R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffcb608a89f R14: 000055653fc0fbe7 R15: 0000000000000003

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_pin_on_cpu include/linux/filter.h:599 [inline]
 bpf_prog_run_clear_cb include/linux/filter.h:721 [inline]
 fanout_demux_bpf net/packet/af_packet.c:1404 [inline]
 packet_rcv_fanout+0x51e/0x25c0 net/packet/af_packet.c:1456
 deliver_skb net/core/dev.c:2168 [inline]
 dev_queue_xmit_nit+0x862/0x1270 net/core/dev.c:2238
 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_finish_output+0xaa7/0xd80 net/ipv4/ip_output.c:306
 ip_finish_output+0x166/0x410 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0x593/0x680 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:435 [inline]
 ip_local_out net/ipv4/ip_output.c:125 [inline]
 __ip_queue_xmit+0x1b5c/0x21a0 net/ipv4/ip_output.c:530
 ip_queue_xmit+0xcc/0xf0 include/net/ip.h:237
 __tcp_transmit_skb+0x4221/0x6090 net/ipv4/tcp_output.c:1238
 tcp_transmit_skb net/ipv4/tcp_output.c:1254 [inline]
 tcp_write_xmit+0x30e1/0xb470 net/ipv4/tcp_output.c:2517
 __tcp_push_pending_frames+0x124/0x4e0 net/ipv4/tcp_output.c:2693
 tcp_push+0x6fa/0x8a0 net/ipv4/tcp.c:725
 tcp_sendmsg_locked+0x5d89/0x6d00 net/ipv4/tcp.c:1403
 tcp_sendmsg+0xb2/0x100 net/ipv4/tcp.c:1433
 inet_sendmsg+0x178/0x2e0 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 sock_write_iter+0x606/0x6d0 net/socket.c:1004
 call_write_iter include/linux/fs.h:1907 [inline]
 new_sync_write fs/read_write.c:484 [inline]
 __vfs_write+0xa5a/0xca0 fs/read_write.c:497
 vfs_write+0x444/0x8e0 fs/read_write.c:559
 ksys_write+0x267/0x450 fs/read_write.c:612
 __do_sys_write fs/read_write.c:624 [inline]
 __se_sys_write+0x92/0xb0 fs/read_write.c:621
 __x64_sys_write+0x4a/0x70 fs/read_write.c:621
 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
=====================================================

Crashes (14):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/05/27 09:29 https://github.com/google/kmsan.git master 94bc4cd0c2f0 9072c126 .config console log report syz C ci-upstream-kmsan-gce
2020/05/28 00:01 https://github.com/google/kmsan.git master 8b611d82b66b ec153193 .config console log report ci-upstream-kmsan-gce
2020/05/27 15:19 https://github.com/google/kmsan.git master 8b611d82b66b ec153193 .config console log report ci-upstream-kmsan-gce
2020/05/27 11:46 https://github.com/google/kmsan.git master 94bc4cd0c2f0 9072c126 .config console log report ci-upstream-kmsan-gce
2020/05/27 08:43 https://github.com/google/kmsan.git master 94bc4cd0c2f0 9072c126 .config console log report ci-upstream-kmsan-gce
2020/05/26 22:41 https://github.com/google/kmsan.git master 94bc4cd0c2f0 9072c126 .config console log report ci-upstream-kmsan-gce
2020/05/26 19:53 https://github.com/google/kmsan.git master 94bc4cd0c2f0 9072c126 .config console log report ci-upstream-kmsan-gce
2020/05/27 18:59 https://github.com/google/kmsan.git master 8b611d82b66b ec153193 .config console log report ci-upstream-kmsan-gce-386
2020/05/27 08:42 https://github.com/google/kmsan.git master 94bc4cd0c2f0 9072c126 .config console log report ci-upstream-kmsan-gce-386
2020/05/27 05:00 https://github.com/google/kmsan.git master 94bc4cd0c2f0 9072c126 .config console log report ci-upstream-kmsan-gce-386
2020/05/27 04:53 https://github.com/google/kmsan.git master 94bc4cd0c2f0 9072c126 .config console log report ci-upstream-kmsan-gce-386
2020/05/27 02:30 https://github.com/google/kmsan.git master 94bc4cd0c2f0 9072c126 .config console log report ci-upstream-kmsan-gce-386
2020/05/26 23:09 https://github.com/google/kmsan.git master 94bc4cd0c2f0 9072c126 .config console log report ci-upstream-kmsan-gce-386
2020/05/26 20:28 https://github.com/google/kmsan.git master 94bc4cd0c2f0 9072c126 .config console log report ci-upstream-kmsan-gce-386
* Struck through repros no longer work on HEAD.