From: Eric Biggers <ebiggers@kernel.org>
To: syzbot <syzbot+1024a649601aa4214ff6@syzkaller.appspotmail.com>
Cc: gregkh@linuxfoundation.org, jslaby@suse.com,
linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com
Subject: Re: KASAN: use-after-free Read in get_work_pool_id
Date: Mon, 24 Feb 2020 10:30:03 -0800 [thread overview]
Message-ID: <20200224183003.GB109047@gmail.com> (raw)
In-Reply-To: <0000000000006af836059f1a9aa5@google.com>
On Fri, Feb 21, 2020 at 10:58:12AM -0800, syzbot wrote:
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit: 11a48a5a Linux 5.6-rc2
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=16554ee6e00000
> kernel config: https://syzkaller.appspot.com/x/.config?x=b1248cc89e4dba4
> dashboard link: https://syzkaller.appspot.com/bug?extid=1024a649601aa4214ff6
> compiler: gcc (GCC) 9.0.0 20181231 (experimental)
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=112d5aa1e00000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16f739d9e00000
>
> Bisection is inconclusive: the bug happens on the oldest tested release.
>
> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10cbc36ee00000
> final crash: https://syzkaller.appspot.com/x/report.txt?x=12cbc36ee00000
> console output: https://syzkaller.appspot.com/x/log.txt?x=14cbc36ee00000
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+1024a649601aa4214ff6@syzkaller.appspotmail.com
>
> ==================================================================
> BUG: KASAN: use-after-free in atomic64_read include/asm-generic/atomic-instrumented.h:836 [inline]
> BUG: KASAN: use-after-free in atomic_long_read include/asm-generic/atomic-long.h:28 [inline]
> BUG: KASAN: use-after-free in get_work_pool_id+0x1c/0xe0 kernel/workqueue.c:732
> Read of size 8 at addr ffff8880a2d36008 by task syz-executor507/9562
>
> CPU: 1 PID: 9562 Comm: syz-executor507 Not tainted 5.6.0-rc2-syzkaller #0
> 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+0x197/0x210 lib/dump_stack.c:118
> print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
> __kasan_report.cold+0x1b/0x32 mm/kasan/report.c:506
> kasan_report+0x12/0x20 mm/kasan/common.c:641
> check_memory_region_inline mm/kasan/generic.c:185 [inline]
> check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192
> __kasan_check_read+0x11/0x20 mm/kasan/common.c:95
> atomic64_read include/asm-generic/atomic-instrumented.h:836 [inline]
> atomic_long_read include/asm-generic/atomic-long.h:28 [inline]
> get_work_pool_id+0x1c/0xe0 kernel/workqueue.c:732
> mark_work_canceling kernel/workqueue.c:743 [inline]
> __cancel_work_timer+0xfa/0x540 kernel/workqueue.c:3120
> cancel_work_sync+0x18/0x20 kernel/workqueue.c:3164
> tty_buffer_cancel_work+0x16/0x20 drivers/tty/tty_buffer.c:613
> release_tty+0x261/0x470 drivers/tty/tty_io.c:1520
> tty_release_struct+0x3c/0x50 drivers/tty/tty_io.c:1629
> tty_release+0xbcb/0xe90 drivers/tty/tty_io.c:1789
> __fput+0x2ff/0x890 fs/file_table.c:280
> ____fput+0x16/0x20 fs/file_table.c:313
> task_work_run+0x145/0x1c0 kernel/task_work.c:113
> exit_task_work include/linux/task_work.h:22 [inline]
> do_exit+0xba9/0x2f50 kernel/exit.c:801
> do_group_exit+0x135/0x360 kernel/exit.c:899
> __do_sys_exit_group kernel/exit.c:910 [inline]
> __se_sys_exit_group kernel/exit.c:908 [inline]
> __x64_sys_exit_group+0x44/0x50 kernel/exit.c:908
> do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x43ff38
> Code: Bad RIP value.
> RSP: 002b:00007fff706d7d78 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38
> RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
> RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
> R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000
>
> Allocated by task 9562:
> save_stack+0x23/0x90 mm/kasan/common.c:72
> set_track mm/kasan/common.c:80 [inline]
> __kasan_kmalloc mm/kasan/common.c:515 [inline]
> __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:488
> kasan_kmalloc+0x9/0x10 mm/kasan/common.c:529
> kmem_cache_alloc_trace+0x158/0x790 mm/slab.c:3551
> kmalloc include/linux/slab.h:555 [inline]
> kzalloc include/linux/slab.h:669 [inline]
> vc_allocate drivers/tty/vt/vt.c:1085 [inline]
> vc_allocate+0x1fc/0x760 drivers/tty/vt/vt.c:1066
> con_install+0x52/0x410 drivers/tty/vt/vt.c:3229
> tty_driver_install_tty drivers/tty/tty_io.c:1228 [inline]
> tty_init_dev drivers/tty/tty_io.c:1341 [inline]
> tty_init_dev+0xf9/0x470 drivers/tty/tty_io.c:1318
> tty_open_by_driver drivers/tty/tty_io.c:1987 [inline]
> tty_open+0x4a5/0xbb0 drivers/tty/tty_io.c:2035
> chrdev_open+0x245/0x6b0 fs/char_dev.c:414
> do_dentry_open+0x4e6/0x1380 fs/open.c:797
> vfs_open+0xa0/0xd0 fs/open.c:914
> do_last fs/namei.c:3490 [inline]
> path_openat+0x12ee/0x3490 fs/namei.c:3607
> do_filp_open+0x192/0x260 fs/namei.c:3637
> do_sys_openat2+0x5eb/0x7e0 fs/open.c:1149
> do_sys_open+0xf2/0x180 fs/open.c:1165
> ksys_open include/linux/syscalls.h:1386 [inline]
> __do_sys_open fs/open.c:1171 [inline]
> __se_sys_open fs/open.c:1169 [inline]
> __x64_sys_open+0x7e/0xc0 fs/open.c:1169
> do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
>
> Freed by task 9566:
> save_stack+0x23/0x90 mm/kasan/common.c:72
> set_track mm/kasan/common.c:80 [inline]
> kasan_set_free_info mm/kasan/common.c:337 [inline]
> __kasan_slab_free+0x102/0x150 mm/kasan/common.c:476
> kasan_slab_free+0xe/0x10 mm/kasan/common.c:485
> __cache_free mm/slab.c:3426 [inline]
> kfree+0x10a/0x2c0 mm/slab.c:3757
> vt_disallocate_all+0x2bd/0x3e0 drivers/tty/vt/vt_ioctl.c:323
> vt_ioctl+0xc38/0x26d0 drivers/tty/vt/vt_ioctl.c:816
> tty_ioctl+0xa37/0x14f0 drivers/tty/tty_io.c:2660
> vfs_ioctl fs/ioctl.c:47 [inline]
> ksys_ioctl+0x123/0x180 fs/ioctl.c:763
> __do_sys_ioctl fs/ioctl.c:772 [inline]
> __se_sys_ioctl fs/ioctl.c:770 [inline]
> __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770
> do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
>
> The buggy address belongs to the object at ffff8880a2d36000
> which belongs to the cache kmalloc-2k of size 2048
> The buggy address is located 8 bytes inside of
> 2048-byte region [ffff8880a2d36000, ffff8880a2d36800)
> The buggy address belongs to the page:
> page:ffffea00028b4d80 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0
> flags: 0xfffe0000000200(slab)
> raw: 00fffe0000000200 ffffea00028bcbc8 ffffea0002915c88 ffff8880aa400e00
> raw: 0000000000000000 ffff8880a2d36000 0000000100000001 0000000000000000
> page dumped because: kasan: bad access detected
>
> Memory state around the buggy address:
> ffff8880a2d35f00: 00 fc fc 00 00 00 00 00 fc fc 00 00 00 00 00 fc
> ffff8880a2d35f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> >ffff8880a2d36000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ^
> ffff8880a2d36080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff8880a2d36100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ==================================================================
#syz dup: KASAN: use-after-free Write in release_tty
(Thread link: https://lkml.kernel.org/lkml/0000000000006663de0598d25ab1@google.com/)
prev parent reply other threads:[~2020-02-24 18:30 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-21 18:58 KASAN: use-after-free Read in get_work_pool_id syzbot
2020-02-24 18:30 ` Eric Biggers [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=20200224183003.GB109047@gmail.com \
--to=ebiggers@kernel.org \
--cc=gregkh@linuxfoundation.org \
--cc=jslaby@suse.com \
--cc=linux-kernel@vger.kernel.org \
--cc=syzbot+1024a649601aa4214ff6@syzkaller.appspotmail.com \
--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.