Date:   Tue, 28 Nov 2017 07:23:01 -0800
From:   syzbot 
        <bot+257f413f0ea433750ffaa72b2748289380957904@...kaller.appspotmail.com>
To:     davem@...emloft.net, herbert@...dor.apana.org.au,
        linux-crypto@...r.kernel.org, linux-kernel@...r.kernel.org,
        syzkaller-bugs@...glegroups.com
Subject: KASAN: use-after-free Read in crypto_chacha20_crypt

Hello,

syzkaller hit the following crash on  
1ea8d039f9edcfefb20d8ddfe136930f6e551529
git://git.cmpxchg.org/linux-mmots.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.
C reproducer is attached
syzkaller reproducer is attached. See https://goo.gl/kgGztJ
for information about syzkaller reproducers


==================================================================
BUG: KASAN: use-after-free in __le32_to_cpup  
include/uapi/linux/byteorder/little_endian.h:58 [inline]
BUG: KASAN: use-after-free in le32_to_cpuvp crypto/chacha20_generic.c:19  
[inline]
BUG: KASAN: use-after-free in crypto_chacha20_init  
crypto/chacha20_generic.c:58 [inline]
BUG: KASAN: use-after-free in crypto_chacha20_crypt+0xaf1/0xbd0  
crypto/chacha20_generic.c:91
Read of size 4 at addr ffff880100000006 by task syzkaller030711/3690

CPU: 0 PID: 3690 Comm: syzkaller030711 Not tainted 4.14.0-mm1+ #25
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:17 [inline]
  dump_stack+0x194/0x257 lib/dump_stack.c:53
  print_address_description+0x73/0x250 mm/kasan/report.c:252
  kasan_report_error mm/kasan/report.c:351 [inline]
  kasan_report+0x25b/0x340 mm/kasan/report.c:409
  __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429
  __le32_to_cpup include/uapi/linux/byteorder/little_endian.h:58 [inline]
  le32_to_cpuvp crypto/chacha20_generic.c:19 [inline]
  crypto_chacha20_init crypto/chacha20_generic.c:58 [inline]
  crypto_chacha20_crypt+0xaf1/0xbd0 crypto/chacha20_generic.c:91
  chacha20_simd+0xe4/0x410 arch/x86/crypto/chacha20_glue.c:78
  crypto_skcipher_decrypt include/crypto/skcipher.h:463 [inline]
  _skcipher_recvmsg crypto/algif_skcipher.c:133 [inline]
  skcipher_recvmsg+0xb06/0xf30 crypto/algif_skcipher.c:164
  skcipher_recvmsg_nokey+0x60/0x80 crypto/algif_skcipher.c:283
  sock_recvmsg_nosec net/socket.c:805 [inline]
  sock_recvmsg+0xc9/0x110 net/socket.c:812
  ___sys_recvmsg+0x29b/0x630 net/socket.c:2207
  __sys_recvmsg+0xe2/0x210 net/socket.c:2252
  SYSC_recvmsg net/socket.c:2264 [inline]
  SyS_recvmsg+0x2d/0x50 net/socket.c:2259
  entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x4465a9
RSP: 002b:00007f95f86dddc8 EFLAGS: 00000202 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004465a9
RDX: 0000000040010101 RSI: 000000002008dfc8 RDI: 0000000000000006
RBP: 0000000000000086 R08: 00007f95f86de700 R09: 00007f95f86de700
R10: 00007f95f86de700 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffd7fbd37cf R14: 00007f95f86de9c0 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea0004000000 count:0 mapcount:-127 mapping:          (null)  
index:0x0
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffff80
raw: ffff88021fffae20 ffffea0004010020 000000000000000a 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
BUG: unable to handle kernel paging request at ffffed001fffffe0
IP: memcpy_erms+0x6/0x10 arch/x86/lib/memcpy_64.S:53
PGD 21ffd6067 P4D 21ffd6067 PUD 21ffd5067 PMD 0
Oops: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
    (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 3690 Comm: syzkaller030711 Not tainted 4.14.0-mm1+ #25
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
task: ffff8801cb608580 task.stack: ffff8801cb610000
RIP: 0010:memcpy_erms+0x6/0x10 arch/x86/lib/memcpy_64.S:53
RSP: 0018:ffff8801cb6174f8 EFLAGS: 00010096
RAX: ffff8801cb617504 RBX: ffffed001fffffe0 RCX: 0000000000000010
RDX: 0000000000000010 RSI: ffffed001fffffe0 RDI: ffff8801cb617504
RBP: ffff8801cb617550 R08: ffffed00396c2ea5 R09: ffffed00396c2ea5
R10: dffffc0000000000 R11: ffffed00396c2ea4 R12: 00000000fffffffe
R13: ffff8800ffffff00 R14: ffffed0020000000 R15: 0000000000000014
FS:  00007f95f86de700(0000) GS:ffff8801db400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffed001fffffe0 CR3: 00000001cbd94000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  kasan_report_error mm/kasan/report.c:353 [inline]
  kasan_report+0x26f/0x340 mm/kasan/report.c:409
  __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429
  __le32_to_cpup include/uapi/linux/byteorder/little_endian.h:58 [inline]
  le32_to_cpuvp crypto/chacha20_generic.c:19 [inline]
  crypto_chacha20_init crypto/chacha20_generic.c:58 [inline]
  crypto_chacha20_crypt+0xaf1/0xbd0 crypto/chacha20_generic.c:91
  chacha20_simd+0xe4/0x410 arch/x86/crypto/chacha20_glue.c:78
  crypto_skcipher_decrypt include/crypto/skcipher.h:463 [inline]
  _skcipher_recvmsg crypto/algif_skcipher.c:133 [inline]
  skcipher_recvmsg+0xb06/0xf30 crypto/algif_skcipher.c:164
  skcipher_recvmsg_nokey+0x60/0x80 crypto/algif_skcipher.c:283
  sock_recvmsg_nosec net/socket.c:805 [inline]
  sock_recvmsg+0xc9/0x110 net/socket.c:812
  ___sys_recvmsg+0x29b/0x630 net/socket.c:2207
  __sys_recvmsg+0xe2/0x210 net/socket.c:2252
  SYSC_recvmsg net/socket.c:2264 [inline]
  SyS_recvmsg+0x2d/0x50 net/socket.c:2259
  entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x4465a9
RSP: 002b:00007f95f86dddc8 EFLAGS: 00000202 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004465a9
RDX: 0000000040010101 RSI: 000000002008dfc8 RDI: 0000000000000006
RBP: 0000000000000086 R08: 00007f95f86de700 R09: 00007f95f86de700
R10: 00007f95f86de700 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffd7fbd37cf R14: 00007f95f86de9c0 R15: 0000000000000000
Code: 90 90 90 90 90 eb 1e 0f 1f 00 48 89 f8 48 89 d1 48 c1 e9 03 83 e2 07  
f3 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 <f3> a4 c3 0f  
1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 7e 40 38
RIP: memcpy_erms+0x6/0x10 arch/x86/lib/memcpy_64.S:53 RSP: ffff8801cb6174f8
CR2: ffffed001fffffe0
---[ end trace 8af5cceb02f4097e ]---


---
This bug is generated by a dumb bot. It may contain errors.
See https://goo.gl/tpsmEJ for details.
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