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KMSAN: uninit-value in ip_tunnel_lookup

Status: closed as invalid on 2018/10/03 18:03
Subsystems: net
[Documentation on labels]
First crash: 2004d, last: 2004d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: uninit-value in ip_tunnel_lookup (2) net C 2 1981d 1982d 11/26 fixed on 2018/11/12 21:25

Sample crash report:
==================================================================
BUG: KMSAN: uninit-value in __read_once_size include/linux/compiler.h:197 [inline]
BUG: KMSAN: uninit-value in ip_tunnel_lookup+0x17b/0x1610 net/ipv4/ip_tunnel.c:108
CPU: 0 PID: 29078 Comm: syz-executor5 Not tainted 4.19.0-rc4+ #62
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x2f6/0x430 lib/dump_stack.c:113
 kmsan_report+0x183/0x2b0 mm/kmsan/kmsan.c:917
 __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:500
 __read_once_size include/linux/compiler.h:197 [inline]
 ip_tunnel_lookup+0x17b/0x1610 net/ipv4/ip_tunnel.c:108
 ipgre_err net/ipv4/ip_gre.c:188 [inline]
 gre_err+0x9b4/0xf00 net/ipv4/ip_gre.c:254
 gre_err+0x1ab/0x200 net/ipv4/gre_demux.c:165
 icmp_socket_deliver net/ipv4/icmp.c:766 [inline]
 icmp_unreach+0xa35/0x1070 net/ipv4/icmp.c:883
 icmp_rcv+0x18d2/0x1a70 net/ipv4/icmp.c:1065
 ip_local_deliver_finish+0x90e/0xfa0 net/ipv4/ip_input.c:215
 NF_HOOK include/linux/netfilter.h:287 [inline]
 ip_local_deliver+0x438/0x4d0 net/ipv4/ip_input.c:256
 dst_input include/net/dst.h:450 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:415 [inline]
 NF_HOOK include/linux/netfilter.h:287 [inline]
 ip_rcv+0x65f/0x6d0 net/ipv4/ip_input.c:524
 __netif_receive_skb_one_core net/core/dev.c:4891 [inline]
 __netif_receive_skb net/core/dev.c:5001 [inline]
 process_backlog+0xd89/0x11a0 net/core/dev.c:5807
 napi_poll net/core/dev.c:6227 [inline]
 net_rx_action+0x935/0x1c00 net/core/dev.c:6293
 __do_softirq+0x614/0xa72 kernel/softirq.c:292
 do_softirq_own_stack+0x49/0x80 arch/x86/entry/entry_64.S:1055
 </IRQ>
 do_softirq kernel/softirq.c:336 [inline]
 __local_bh_enable_ip+0x119/0x150 kernel/softirq.c:189
 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32
 rcu_read_unlock_bh include/linux/rcupdate.h:723 [inline]
 ip_finish_output2+0x13cd/0x14f0 net/ipv4/ip_output.c:231
 ip_finish_output+0xd0a/0x10a0 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:276 [inline]
 ip_output+0x50f/0x5d0 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:444 [inline]
 ip_local_out net/ipv4/ip_output.c:124 [inline]
 ip_send_skb net/ipv4/ip_output.c:1441 [inline]
 ip_push_pending_frames+0x230/0x420 net/ipv4/ip_output.c:1461
 raw_sendmsg+0x2a48/0x3f90 net/ipv4/raw.c:677
 inet_sendmsg+0x4c5/0x7d0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x868/0xa30 net/socket.c:1786
 __do_sys_sendto net/socket.c:1798 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1794
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1794
 do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x457579
Code: 1d b4 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 eb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f650ce2dc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457579
RDX: 000000000000029c RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 000000000072bf00 R08: 0000000020000080 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f650ce2e6d4
R13: 00000000004c3929 R14: 00000000004d57c0 R15: 00000000ffffffff

Local variable description: ----tpi@gre_err
Variable was created at:
 gre_err+0x5c/0xf00 net/ipv4/ip_gre.c:216
 gre_err+0x1ab/0x200 net/ipv4/gre_demux.c:165
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/10/02 16:11 https://github.com/google/kmsan.git master b2efdb2ef006 a316a2af .config console log report ci-upstream-kmsan-gce
* Struck through repros no longer work on HEAD.