Subject: kernel BUG at net/core/skbuff.c:LINE! (2)

From: syzbot <[email-masked]>
Date: Mon, 30 Oct 2017 07:36:03 -0700

Hello,

syzkaller hit the following crash on  
c69fe407803d4b554b7397fad9598a04717ac255
git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.

sctp: [Deprecated]: syz-executor0 (pid 12122) Use of struct  
sctp_assoc_value in delayed_ack socket option.
Use struct sctp_sack_info instead
skbuff: skb_over_panic: text:ffffffff848208a3 len:213348 put:213008  
head:ffff8801c99c2140 data:ffff8801c99c21f8 tail:0x3421c end:0x7ec0  
dev:<NULL>
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:105!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
    (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 12167 Comm: syz-executor5 Not tainted 4.14.0-rc5+ #100
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
task: ffff8801cd7ba3c0 task.stack: ffff8801c1fc0000
RIP: 0010:skb_panic+0x15c/0x1f0 net/core/skbuff.c:101
RSP: 0018:ffff8801c1fc63a8 EFLAGS: 00010286
RAX: 0000000000000092 RBX: ffff8801a91dc680 RCX: 0000000000000000
RDX: 0000000000000092 RSI: ffffffff8158d77e RDI: ffffed00383f8c69
RBP: ffff8801c1fc6410 R08: 0000000000000000 R09: 1ffff100383f8c17
R10: 000000006d0a2354 R11: ffffffff85b2cc98 R12: ffffffff853bcca0
R13: ffffffff848208a3 R14: 0000000000034010 R15: ffffffff853bc4e0
FS:  00007fbe84337700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020001f68 CR3: 00000001c9045000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  skb_over_panic net/core/skbuff.c:110 [inline]
  skb_put+0x181/0x1c0 net/core/skbuff.c:1699
  skb_put_data include/linux/skbuff.h:2047 [inline]
  sctp_packet_pack net/sctp/output.c:472 [inline]
  sctp_packet_transmit+0x1183/0x3750 net/sctp/output.c:605
  sctp_outq_flush+0x1216/0x4050 net/sctp/outqueue.c:1191
  sctp_outq_uncork+0x5a/0x70 net/sctp/outqueue.c:772
  sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1822 [inline]
  sctp_side_effects net/sctp/sm_sideeffect.c:1222 [inline]
  sctp_do_sm+0x50e/0x6a30 net/sctp/sm_sideeffect.c:1193
  sctp_assoc_bh_rcv+0x283/0x4b0 net/sctp/associola.c:1065
  sctp_inq_push+0x23b/0x300 net/sctp/inqueue.c:95
  sctp_backlog_rcv+0x177/0xaa0 net/sctp/input.c:350
  sk_backlog_rcv include/net/sock.h:912 [inline]
  __release_sock+0x124/0x360 net/core/sock.c:2266
  release_sock+0xa4/0x2a0 net/core/sock.c:2778
  sctp_wait_for_connect+0x346/0x570 net/sctp/socket.c:8099
  sctp_sendmsg+0x29fd/0x32b0 net/sctp/socket.c:2009
  inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763
  sock_sendmsg_nosec net/socket.c:633 [inline]
  sock_sendmsg+0xca/0x110 net/socket.c:643
  SYSC_sendto+0x352/0x5a0 net/socket.c:1750
  SyS_sendto+0x40/0x50 net/socket.c:1718
  entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x452869
RSP: 002b:00007fbe84336be8 EFLAGS: 00000212 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000758020 RCX: 0000000000452869
RDX: 0000000000034000 RSI: 0000000020c9bfff RDI: 0000000000000013
RBP: 0000000000000000 R08: 0000000020a46000 R09: 000000000000001c
R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000
R13: 0000000000a6f7ff R14: 00007fbe843379c0 R15: 0000000000000000
Code: 03 0f b6 04 01 84 c0 74 04 3c 03 7e 20 8b 4b 78 41 57 48 c7 c7 20 c5  
3b 85 52 56 4c 89 ea 41 50 4c 89 e6 45 89 f0 e8 b9 19 77 fd <0f> 0b 4c 89  
4d b8 4c 89 45 c0 48 89 75 c8 48 89 55 d0 e8 6d 4b
RIP: skb_panic+0x15c/0x1f0 net/core/skbuff.c:101 RSP: ffff8801c1fc63a8
---[ end trace 6beb4fe15730f020 ]---

---
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