syzbot

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BUG: KMSAN: uninit-value in packet_snd net/packet/af_packet.c:2882 [inline]
BUG: KMSAN: uninit-value in packet_sendmsg+0x8017/0x9180 net/packet/af_packet.c:2953
CPU: 1 PID: 19307 Comm: syz-executor1 Not tainted 4.20.0-rc3+ #93
sctp: [Deprecated]: syz-executor5 (pid 19311) Use of struct sctp_assoc_value in delayed_ack socket option.
Use struct sctp_sack_info instead
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+0x32d/0x480 lib/dump_stack.c:113
 kmsan_report+0x19f/0x300 mm/kmsan/kmsan.c:831
 __msan_warning+0x76/0xc0 mm/kmsan/kmsan_instr.c:410
 packet_snd net/packet/af_packet.c:2882 [inline]
 packet_sendmsg+0x8017/0x9180 net/packet/af_packet.c:2953
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x940/0xb80 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x457569
sctp: [Deprecated]: syz-executor5 (pid 19313) Use of struct sctp_assoc_value in delayed_ack socket option.
Use struct sctp_sack_info instead
Code: fd b3 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 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f6a29496c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 0000000000457569
RDX: 000000000000026b RSI: 0000000020000040 RDI: 0000000000000003
RBP: 000000000072bf00 R08: 0000000020000000 R09: 0000000000000014
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f6a294976d4
R13: 00000000004c409e R14: 00000000004d6958 R15: 00000000ffffffff

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:258 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:273 [inline]
 kmsan_internal_chain_origin+0x13d/0x240 mm/kmsan/kmsan.c:486
 kmsan_memcpy_memmove_metadata+0x1a9/0xf70 mm/kmsan/kmsan.c:357
 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:375
 __msan_memcpy+0x61/0x70 mm/kmsan/kmsan_instr.c:236
 ip6gre_header+0x5f6/0xa40 net/ipv6/ip6_gre.c:1351
 dev_hard_header include/linux/netdevice.h:2916 [inline]
 packet_snd net/packet/af_packet.c:2881 [inline]
 packet_sendmsg+0x6b93/0x9180 net/packet/af_packet.c:2953
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x940/0xb80 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Local variable description: ----address@__sys_sendto
Variable was created at:
 __sys_sendto+0xe5/0xb80 net/socket.c:1759
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
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