All of lore.kernel.org
 help / color / mirror / Atom feed
From: syzbot <syzbot+12056a09a0311d758e60@syzkaller.appspotmail.com>
To: axboe@kernel.dk, io-uring@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	syzkaller-bugs@googlegroups.com, viro@zeniv.linux.org.uk
Subject: KASAN: use-after-free Read in idr_for_each (2)
Date: Mon, 05 Oct 2020 01:56:17 -0700	[thread overview]
Message-ID: <000000000000ca835605b0e8a723@google.com> (raw)

Hello,

syzbot found the following issue on:

HEAD commit:    472e5b05 pipe: remove pipe_wait() and fix wakeup race with..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15ae0d47900000
kernel config:  https://syzkaller.appspot.com/x/.config?x=89ab6a0c48f30b49
dashboard link: https://syzkaller.appspot.com/bug?extid=12056a09a0311d758e60
compiler:       gcc (GCC) 10.1.0-syz 20200507
userspace arch: i386

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+12056a09a0311d758e60@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in radix_tree_next_slot include/linux/radix-tree.h:421 [inline]
BUG: KASAN: use-after-free in idr_for_each+0x206/0x220 lib/idr.c:202
Read of size 8 at addr ffff88804eb9cb30 by task kworker/u4:8/13668

CPU: 1 PID: 13668 Comm: kworker/u4:8 Not tainted 5.9.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound io_ring_exit_work
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x198/0x1fd lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 radix_tree_next_slot include/linux/radix-tree.h:421 [inline]
 idr_for_each+0x206/0x220 lib/idr.c:202
 io_destroy_buffers fs/io_uring.c:7889 [inline]
 io_ring_ctx_free fs/io_uring.c:7904 [inline]
 io_ring_exit_work+0x363/0x6d0 fs/io_uring.c:7979
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Allocated by task 17016:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461
 slab_post_alloc_hook mm/slab.h:518 [inline]
 slab_alloc mm/slab.c:3316 [inline]
 kmem_cache_alloc+0x13a/0x3f0 mm/slab.c:3486
 radix_tree_node_alloc.constprop.0+0x7c/0x350 lib/radix-tree.c:275
 idr_get_free+0x4c5/0x940 lib/radix-tree.c:1505
 idr_alloc_u32+0x170/0x2d0 lib/idr.c:46
 idr_alloc+0xc2/0x130 lib/idr.c:87
 io_provide_buffers fs/io_uring.c:3768 [inline]
 io_issue_sqe+0x48d2/0x5c50 fs/io_uring.c:5906
 __io_queue_sqe+0x280/0x1160 fs/io_uring.c:6178
 io_queue_sqe+0x692/0xfa0 fs/io_uring.c:6257
 io_submit_sqe fs/io_uring.c:6327 [inline]
 io_submit_sqes+0x1759/0x23f0 fs/io_uring.c:6521
 __do_sys_io_uring_enter+0xeac/0x1bd0 fs/io_uring.c:8349
 do_syscall_32_irqs_on arch/x86/entry/common.c:78 [inline]
 __do_fast_syscall_32+0x60/0x90 arch/x86/entry/common.c:137
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:160
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Freed by task 16:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56
 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355
 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422
 __cache_free mm/slab.c:3422 [inline]
 kmem_cache_free.part.0+0x74/0x1e0 mm/slab.c:3697
 rcu_do_batch kernel/rcu/tree.c:2430 [inline]
 rcu_core+0x5ca/0x1130 kernel/rcu/tree.c:2658
 __do_softirq+0x1f8/0xb23 kernel/softirq.c:298

Last call_rcu():
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_record_aux_stack+0x82/0xb0 mm/kasan/generic.c:346
 __call_rcu kernel/rcu/tree.c:2896 [inline]
 call_rcu+0x15e/0x7c0 kernel/rcu/tree.c:2970
 radix_tree_node_free lib/radix-tree.c:309 [inline]
 delete_node+0x591/0x8c0 lib/radix-tree.c:572
 __radix_tree_delete+0x190/0x370 lib/radix-tree.c:1378
 radix_tree_delete_item+0xe7/0x230 lib/radix-tree.c:1429
 __io_remove_buffers fs/io_uring.c:3666 [inline]
 __io_remove_buffers fs/io_uring.c:3645 [inline]
 __io_destroy_buffers+0x161/0x200 fs/io_uring.c:7883
 idr_for_each+0x113/0x220 lib/idr.c:208
 io_destroy_buffers fs/io_uring.c:7889 [inline]
 io_ring_ctx_free fs/io_uring.c:7904 [inline]
 io_ring_exit_work+0x363/0x6d0 fs/io_uring.c:7979
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Second to last call_rcu():
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_record_aux_stack+0x82/0xb0 mm/kasan/generic.c:346
 __call_rcu kernel/rcu/tree.c:2896 [inline]
 call_rcu+0x15e/0x7c0 kernel/rcu/tree.c:2970
 radix_tree_node_free lib/radix-tree.c:309 [inline]
 radix_tree_shrink lib/radix-tree.c:535 [inline]
 delete_node+0x37a/0x8c0 lib/radix-tree.c:553
 __radix_tree_delete+0x190/0x370 lib/radix-tree.c:1378
 radix_tree_delete_item+0xe7/0x230 lib/radix-tree.c:1429
 free_pid+0xa1/0x260 kernel/pid.c:151
 __change_pid+0x1c7/0x2d0 kernel/pid.c:352
 __unhash_process kernel/exit.c:77 [inline]
 __exit_signal kernel/exit.c:147 [inline]
 release_task+0xd29/0x14d0 kernel/exit.c:198
 wait_task_zombie kernel/exit.c:1088 [inline]
 wait_consider_task+0x2fd2/0x3b70 kernel/exit.c:1315
 do_wait_thread kernel/exit.c:1378 [inline]
 do_wait+0x376/0xa00 kernel/exit.c:1449
 kernel_wait4+0x14c/0x260 kernel/exit.c:1621
 do_syscall_32_irqs_on arch/x86/entry/common.c:78 [inline]
 __do_fast_syscall_32+0x60/0x90 arch/x86/entry/common.c:137
 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:160
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

The buggy address belongs to the object at ffff88804eb9cb00
 which belongs to the cache radix_tree_node of size 576
The buggy address is located 48 bytes inside of
 576-byte region [ffff88804eb9cb00, ffff88804eb9cd40)
The buggy address belongs to the page:
page:00000000a35d3b6e refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88804eb9cffb pfn:0x4eb9c
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea00013ab388 ffffea0002927748 ffff8880aa06f000
raw: ffff88804eb9cffb ffff88804eb9c000 0000000100000005 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88804eb9ca00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804eb9ca80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88804eb9cb00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88804eb9cb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804eb9cc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
This report 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 issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

             reply	other threads:[~2020-10-05  8:56 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-10-05  8:56 syzbot [this message]
2020-11-28 17:19 ` KASAN: use-after-free Read in idr_for_each (2) syzbot
2020-12-18 15:43   ` Pavel Begunkov
2020-12-18 16:44     ` syzbot
2021-03-19 10:38       ` Pavel Begunkov
2021-03-19 11:02         ` [syzbot] " syzbot
     [not found] ` <20201129113429.13660-1-hdanton@sina.com>
2020-11-29 12:26   ` Matthew Wilcox
2020-11-30 17:43     ` Jens Axboe
2021-04-15 18:28 ` [syzbot] " syzbot
2021-04-19 12:09   ` Pavel Begunkov

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=000000000000ca835605b0e8a723@google.com \
    --to=syzbot+12056a09a0311d758e60@syzkaller.appspotmail.com \
    --cc=axboe@kernel.dk \
    --cc=io-uring@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=syzkaller-bugs@googlegroups.com \
    --cc=viro@zeniv.linux.org.uk \
    /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.