syzbot

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BUG: KMSAN: uninit-value in crc32c_intel_le_hw arch/x86/crypto/crc32c-intel_glue.c:81 [inline]
BUG: KMSAN: uninit-value in crc32c_pcl_intel_update+0x2af/0x500 arch/x86/crypto/crc32c-intel_glue.c:185
CPU: 0 PID: 3577 Comm: syzkaller253015 Not tainted 4.16.0+ #83
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676
 crc32c_intel_le_hw arch/x86/crypto/crc32c-intel_glue.c:81 [inline]
 crc32c_pcl_intel_update+0x2af/0x500 arch/x86/crypto/crc32c-intel_glue.c:185
 crypto_shash_update+0x1e9/0x210 crypto/shash.c:117
 crc32c+0x155/0x210 lib/libcrc32c.c:53
 sctp_csum_update+0x89/0xa0 include/net/sctp/checksum.h:51
 __skb_checksum+0x234/0x1010 net/core/skbuff.c:2471
 sctp_compute_cksum include/net/sctp/checksum.h:73 [inline]
 sctp_rcv_checksum net/sctp/input.c:83 [inline]
 sctp_rcv+0xf4e/0x4c90 net/sctp/input.c:139
 ip_local_deliver_finish+0x6ed/0xd40 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_local_deliver+0x43c/0x4e0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:449 [inline]
 ip_rcv_finish+0x1253/0x16d0 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_rcv+0x119d/0x16f0 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x47cf/0x4a80 net/core/dev.c:4562
 __netif_receive_skb net/core/dev.c:4627 [inline]
 process_backlog+0x62d/0xe20 net/core/dev.c:5307
 napi_poll net/core/dev.c:5705 [inline]
 net_rx_action+0x7c1/0x1a70 net/core/dev.c:5771
 __do_softirq+0x56d/0x93d kernel/softirq.c:285
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1040
 </IRQ>
 do_softirq kernel/softirq.c:329 [inline]
 __local_bh_enable_ip+0x114/0x140 kernel/softirq.c:182
 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32
 rcu_read_unlock_bh include/linux/rcupdate.h:726 [inline]
 ip_finish_output2+0x124e/0x1380 net/ipv4/ip_output.c:231
 ip_finish_output+0xcb0/0xff0 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:277 [inline]
 ip_output+0x502/0x5c0 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:443 [inline]
 ip_local_out net/ipv4/ip_output.c:124 [inline]
 ip_send_skb+0x5f3/0x820 net/ipv4/ip_output.c:1414
 ip_push_pending_frames+0x105/0x170 net/ipv4/ip_output.c:1434
 raw_sendmsg+0x2960/0x3ed0 net/ipv4/raw.c:684
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x43fde9
RSP: 002b:00007ffe3a15f558 EFLAGS: 00000217 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fde9
RDX: 000000000000001c RSI: 0000000020000000 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 00000000200000c0 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000401710
R13: 00000000004017a0 R14: 0000000000000000 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:293 [inline]
 kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684
 kmsan_memcpy_origins+0x11d/0x170 mm/kmsan/kmsan.c:526
 __msan_memcpy+0x19f/0x1f0 mm/kmsan/kmsan_instr.c:470
 skb_copy_bits+0x63a/0xdb0 net/core/skbuff.c:2046
 __pskb_pull_tail+0x483/0x22e0 net/core/skbuff.c:1883
 __skb_linearize include/linux/skbuff.h:3025 [inline]
 skb_linearize include/linux/skbuff.h:3037 [inline]
 sctp_rcv+0x673/0x4c90 net/sctp/input.c:127
 ip_local_deliver_finish+0x6ed/0xd40 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_local_deliver+0x43c/0x4e0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:449 [inline]
 ip_rcv_finish+0x1253/0x16d0 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ip_rcv+0x119d/0x16f0 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x47cf/0x4a80 net/core/dev.c:4562
 __netif_receive_skb net/core/dev.c:4627 [inline]
 process_backlog+0x62d/0xe20 net/core/dev.c:5307
 napi_poll net/core/dev.c:5705 [inline]
 net_rx_action+0x7c1/0x1a70 net/core/dev.c:5771
 __do_softirq+0x56d/0x93d kernel/softirq.c:285
Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_alloc_meta_for_pages+0x161/0x3a0 mm/kmsan/kmsan.c:814
 kmsan_alloc_page+0x82/0xe0 mm/kmsan/kmsan.c:868
 __alloc_pages_nodemask+0xf5b/0x5dc0 mm/page_alloc.c:4283
 alloc_pages_current+0x6b5/0x970 mm/mempolicy.c:2055
 alloc_pages include/linux/gfp.h:494 [inline]
 skb_page_frag_refill+0x3ba/0x5e0 net/core/sock.c:2208
 sk_page_frag_refill+0xa4/0x340 net/core/sock.c:2228
 __ip_append_data+0x107e/0x3d10 net/ipv4/ip_output.c:1057
 ip_append_data+0x2fb/0x440 net/ipv4/ip_output.c:1170
 raw_sendmsg+0x287b/0x3ed0 net/ipv4/raw.c:678
 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747
 SyS_sendto+0x8a/0xb0 net/socket.c:1715
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
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