All of lore.kernel.org
 help / color / mirror / Atom feed
From: syzbot <syzbot+6939a606a5305e9e9799@syzkaller.appspotmail.com>
To: davem@davemloft.net, herbert@gondor.apana.org.au,
	linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
	syzkaller-bugs@googlegroups.com
Subject: KASAN: use-after-free Read in skcipher_recvmsg
Date: Thu, 01 Nov 2018 07:33:02 -0700	[thread overview]
Message-ID: <000000000000d8053d05799b4b86@google.com> (raw)

Hello,

syzbot found the following crash on:

HEAD commit:    59fc453b21f7 Merge branch 'akpm' (patches from Andrew)
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14bc682b400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ea045471e4c756e8
dashboard link: https://syzkaller.appspot.com/bug?extid=6939a606a5305e9e9799
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+6939a606a5305e9e9799@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in crypto_stat_skcipher_decrypt  
include/crypto/skcipher.h:510 [inline]
BUG: KASAN: use-after-free in crypto_skcipher_decrypt  
include/crypto/skcipher.h:559 [inline]
BUG: KASAN: use-after-free in _skcipher_recvmsg crypto/algif_skcipher.c:131  
[inline]
BUG: KASAN: use-after-free in skcipher_recvmsg+0x160f/0x1780  
crypto/algif_skcipher.c:165
Read of size 4 at addr ffff8801b69239c0 by task syz-executor3/23539

CPU: 0 PID: 23539 Comm: syz-executor3 Not tainted 4.19.0+ #313
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+0x244/0x39d lib/dump_stack.c:113
  print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256
  kasan_report_error mm/kasan/report.c:354 [inline]
  kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412
  __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
  crypto_stat_skcipher_decrypt include/crypto/skcipher.h:510 [inline]
  crypto_skcipher_decrypt include/crypto/skcipher.h:559 [inline]
  _skcipher_recvmsg crypto/algif_skcipher.c:131 [inline]
  skcipher_recvmsg+0x160f/0x1780 crypto/algif_skcipher.c:165
  sock_recvmsg_nosec net/socket.c:794 [inline]
  sock_recvmsg+0xd0/0x110 net/socket.c:801
  sock_read_iter+0x39b/0x570 net/socket.c:878
kvm [23531]: vcpu0, guest rIP: 0xfff0 unimplemented HWCR wrmsr: 0x80000280
  call_read_iter include/linux/fs.h:1833 [inline]
  aio_read+0x297/0x490 fs/aio.c:1516
  io_submit_one+0xac2/0xf80 fs/aio.c:1832
  __do_sys_io_submit fs/aio.c:1916 [inline]
  __se_sys_io_submit fs/aio.c:1887 [inline]
  __x64_sys_io_submit+0x1b7/0x580 fs/aio.c:1887
  do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
binder: 23534:23545 ioctl c018620b 20000340 returned -14
RIP: 0033:0x457569
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:00007f351c0cdc78 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 0000000020bd9fe0 RSI: 0000000000000001 RDI: 00007f351c0ad000
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f351c0ce6d4
R13: 00000000004be72d R14: 00000000004ce600 R15: 00000000ffffffff

Allocated by task 23539:
  save_stack+0x43/0xd0 mm/kasan/kasan.c:448
  set_track mm/kasan/kasan.c:460 [inline]
  kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553
  __do_kmalloc mm/slab.c:3722 [inline]
  __kmalloc+0x15b/0x760 mm/slab.c:3731
  kmalloc include/linux/slab.h:551 [inline]
  sock_kmalloc+0x15a/0x1f0 net/core/sock.c:1984
  af_alg_alloc_areq+0x83/0x280 crypto/af_alg.c:1097
  _skcipher_recvmsg crypto/algif_skcipher.c:75 [inline]
  skcipher_recvmsg+0x354/0x1780 crypto/algif_skcipher.c:165
  sock_recvmsg_nosec net/socket.c:794 [inline]
  sock_recvmsg+0xd0/0x110 net/socket.c:801
  sock_read_iter+0x39b/0x570 net/socket.c:878
  call_read_iter include/linux/fs.h:1833 [inline]
  aio_read+0x297/0x490 fs/aio.c:1516
  io_submit_one+0xac2/0xf80 fs/aio.c:1832
  __do_sys_io_submit fs/aio.c:1916 [inline]
  __se_sys_io_submit fs/aio.c:1887 [inline]
  __x64_sys_io_submit+0x1b7/0x580 fs/aio.c:1887
  do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 19019:
  save_stack+0x43/0xd0 mm/kasan/kasan.c:448
  set_track mm/kasan/kasan.c:460 [inline]
  __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
  kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
  __cache_free mm/slab.c:3498 [inline]
  kfree+0xcf/0x230 mm/slab.c:3817
  __sock_kfree_s net/core/sock.c:2005 [inline]
  sock_kfree_s+0x29/0x60 net/core/sock.c:2011
  af_alg_free_resources+0x6b/0x80 crypto/af_alg.c:1033
  af_alg_async_cb+0xbc/0x180 crypto/af_alg.c:1056
  cryptd_skcipher_complete+0x14c/0x250 crypto/cryptd.c:474
  cryptd_skcipher_decrypt+0x4e2/0x750 crypto/cryptd.c:534
  cryptd_queue_worker+0x12d/0x200 crypto/cryptd.c:193
  process_one_work+0xc90/0x1c40 kernel/workqueue.c:2153
  worker_thread+0x17f/0x1390 kernel/workqueue.c:2296
  kthread+0x35a/0x440 kernel/kthread.c:246
  ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:350

The buggy address belongs to the object at ffff8801b69236c0
  which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 768 bytes inside of
  1024-byte region [ffff8801b69236c0, ffff8801b6923ac0)
The buggy address belongs to the page:
page:ffffea0006da4880 count:1 mapcount:0 mapping:ffff8801da800ac0  
index:0xffff8801b6922940 compound_mapcount: 0
flags: 0x2fffc0000010200(slab|head)
raw: 02fffc0000010200 ffffea00070a7b08 ffffea00063a1608 ffff8801da800ac0
kvm [23547]: vcpu0, guest rIP: 0xfff0 unimplemented HWCR wrmsr: 0x80000280
raw: ffff8801b6922940 ffff8801b6922040 0000000100000006 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
  ffff8801b6923880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff8801b6923900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff8801b6923980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                            ^
  ffff8801b6923a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff8801b6923a80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with  
syzbot.

             reply	other threads:[~2018-11-01 23:36 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-11-01 14:33 syzbot [this message]
2018-11-03 22:35 ` KASAN: use-after-free Read in skcipher_recvmsg Eric Biggers
2018-11-04 11:18   ` LABBE Corentin

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=000000000000d8053d05799b4b86@google.com \
    --to=syzbot+6939a606a5305e9e9799@syzkaller.appspotmail.com \
    --cc=davem@davemloft.net \
    --cc=herbert@gondor.apana.org.au \
    --cc=linux-crypto@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=syzkaller-bugs@googlegroups.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.