All of lore.kernel.org
 help / color / mirror / Atom feed
From: syzbot <syzbot+04babcefcd396fabec37@syzkaller.appspotmail.com>
To: -O-request@vger.kernel.org, andrew.hendry@gmail.com,
	davem@davemloft.net, dvlasenk@redhat.com, edumazet@google.com,
	gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
	linux-x25@vger.kernel.org, ms@dev.tdt.de, netdev@vger.kernel.org,
	syzkaller-bugs@googlegroups.com
Subject: Re: KASAN: use-after-free Read in x25_device_event
Date: Sun, 10 Mar 2019 07:56:05 -0700	[thread overview]
Message-ID: <000000000000c3ba940583bea717@google.com> (raw)
In-Reply-To: <000000000000cdc755057e2da575@google.com>

syzbot has found a reproducer for the following crash on:

HEAD commit:    d9862cfb Merge tag 'mips_5.1' of git://git.kernel.org/pub/..
git tree:       net-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1531cf23200000
kernel config:  https://syzkaller.appspot.com/x/.config?x=73d88a42238825ad
dashboard link: https://syzkaller.appspot.com/bug?extid=04babcefcd396fabec37
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
userspace arch: amd64
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=100ffdad200000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=16c2599d200000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+04babcefcd396fabec37@syzkaller.appspotmail.com

device ifb0 entered promiscuous mode
device ifb0 left promiscuous mode
device ifb0 entered promiscuous mode
device ifb0 left promiscuous mode
==================================================================
BUG: KASAN: use-after-free in x25_kill_by_device net/x25/af_x25.c:217  
[inline]
BUG: KASAN: use-after-free in x25_device_event+0x296/0x2b0  
net/x25/af_x25.c:252
Read of size 8 at addr ffff8880a030edd0 by task syz-executor003/7854

CPU: 0 PID: 7854 Comm: syz-executor003 Not tainted 5.0.0+ #97
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+0x172/0x1f0 lib/dump_stack.c:113
  print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
  kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
  __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
  x25_kill_by_device net/x25/af_x25.c:217 [inline]
  x25_device_event+0x296/0x2b0 net/x25/af_x25.c:252
  notifier_call_chain+0xc7/0x240 kernel/notifier.c:93
  __raw_notifier_call_chain kernel/notifier.c:394 [inline]
  raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401
  call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1739
  call_netdevice_notifiers_extack net/core/dev.c:1751 [inline]
  call_netdevice_notifiers net/core/dev.c:1765 [inline]
  __dev_notify_flags+0x1e9/0x2c0 net/core/dev.c:7607
  dev_change_flags+0x10d/0x170 net/core/dev.c:7643
  dev_ifsioc+0x2b0/0x940 net/core/dev_ioctl.c:237
  dev_ioctl+0x1b8/0xc70 net/core/dev_ioctl.c:488
  sock_do_ioctl+0x1bd/0x300 net/socket.c:995
  sock_ioctl+0x32b/0x610 net/socket.c:1096
  vfs_ioctl fs/ioctl.c:46 [inline]
  file_ioctl fs/ioctl.c:509 [inline]
  do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
  ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
  __do_sys_ioctl fs/ioctl.c:720 [inline]
  __se_sys_ioctl fs/ioctl.c:718 [inline]
  __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
  do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4467c9
Code: e8 0c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 5b 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fdbea222d98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000006dbc58 RCX: 00000000004467c9
RDX: 0000000020000340 RSI: 0000000000008914 RDI: 0000000000000003
RBP: 00000000006dbc50 R08: 00007fdbea223700 R09: 0000000000000000
R10: 00007fdbea223700 R11: 0000000000000246 R12: 00000000006dbc5c
R13: 6000030030626669 R14: 0000000000000000 R15: 0000000030626669

Allocated by task 7843:
  save_stack+0x45/0xd0 mm/kasan/common.c:73
  set_track mm/kasan/common.c:85 [inline]
  __kasan_kmalloc mm/kasan/common.c:495 [inline]
  __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:468
  kasan_kmalloc+0x9/0x10 mm/kasan/common.c:509
  kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3615
  kmalloc include/linux/slab.h:545 [inline]
  x25_link_device_up+0x46/0x3f0 net/x25/x25_link.c:249
  x25_device_event+0x116/0x2b0 net/x25/af_x25.c:242
  notifier_call_chain+0xc7/0x240 kernel/notifier.c:93
  __raw_notifier_call_chain kernel/notifier.c:394 [inline]
  raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401
  call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1739
  call_netdevice_notifiers_extack net/core/dev.c:1751 [inline]
  call_netdevice_notifiers net/core/dev.c:1765 [inline]
  __dev_notify_flags+0x121/0x2c0 net/core/dev.c:7605
  dev_change_flags+0x10d/0x170 net/core/dev.c:7643
  dev_ifsioc+0x2b0/0x940 net/core/dev_ioctl.c:237
  dev_ioctl+0x1b8/0xc70 net/core/dev_ioctl.c:488
  sock_do_ioctl+0x1bd/0x300 net/socket.c:995
  sock_ioctl+0x32b/0x610 net/socket.c:1096
  vfs_ioctl fs/ioctl.c:46 [inline]
  file_ioctl fs/ioctl.c:509 [inline]
  do_vfs_ioctl+0xd6e/0x1390 fs/ioctl.c:696
  ksys_ioctl+0xab/0xd0 fs/ioctl.c:713
  __do_sys_ioctl fs/ioctl.c:720 [inline]
  __se_sys_ioctl fs/ioctl.c:718 [inline]
  __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
  do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 7865:
  save_stack+0x45/0xd0 mm/kasan/common.c:73
  set_track mm/kasan/common.c:85 [inline]
  __kasan_slab_free+0x102/0x150 mm/kasan/common.c:457
  kasan_slab_free+0xe/0x10 mm/kasan/common.c:465
  __cache_free mm/slab.c:3494 [inline]
  kfree+0xcf/0x230 mm/slab.c:3811
  x25_neigh_put include/net/x25.h:253 [inline]
  x25_connect+0x8d8/0xde0 net/x25/af_x25.c:824
  __sys_connect+0x266/0x330 net/socket.c:1685
  __do_sys_connect net/socket.c:1696 [inline]
  __se_sys_connect net/socket.c:1693 [inline]
  __x64_sys_connect+0x73/0xb0 net/socket.c:1693
  do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8880a030edc0
  which belongs to the cache kmalloc-256 of size 256
The buggy address is located 16 bytes inside of
  256-byte region [ffff8880a030edc0, ffff8880a030eec0)
The buggy address belongs to the page:
page:ffffea000280c380 count:1 mapcount:0 mapping:ffff88812c3f07c0 index:0x0
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea0002806788 ffffea00027f0188 ffff88812c3f07c0
raw: 0000000000000000 ffff8880a030e000 000000010000000c 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
  ffff8880a030ec80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff8880a030ed00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff8880a030ed80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                                  ^
  ffff8880a030ee00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff8880a030ee80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================


      reply	other threads:[~2019-03-10 14:56 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-12-29 18:50 KASAN: use-after-free Read in x25_device_event syzbot
2019-03-10 14:56 ` syzbot [this message]

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=000000000000c3ba940583bea717@google.com \
    --to=syzbot+04babcefcd396fabec37@syzkaller.appspotmail.com \
    --cc=-O-request@vger.kernel.org \
    --cc=andrew.hendry@gmail.com \
    --cc=davem@davemloft.net \
    --cc=dvlasenk@redhat.com \
    --cc=edumazet@google.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-x25@vger.kernel.org \
    --cc=ms@dev.tdt.de \
    --cc=netdev@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.