linux-usb.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* KASAN: use-after-free Read in usb_autopm_put_interface
@ 2019-10-15 15:51 syzbot
  2019-10-15 17:55 ` [PATCH] USB: usblp: fix use-after-free on disconnect Johan Hovold
  0 siblings, 1 reply; 2+ messages in thread
From: syzbot @ 2019-10-15 15:51 UTC (permalink / raw)
  To: andreyknvl, gregkh, kai.heng.feng, linux-kernel, linux-usb,
	stern, syzkaller-bugs

Hello,

syzbot found the following crash on:

HEAD commit:    22be26f7 usb-fuzzer: main usb gadget fuzzer driver
git tree:       https://github.com/google/kasan.git usb-fuzzer
console output: https://syzkaller.appspot.com/x/log.txt?x=174dc008e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=387eccb7ac68ec5
dashboard link: https://syzkaller.appspot.com/bug?extid=cd24df4d075c319ebfc5
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=145d2e6f600000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11ce4473600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+cd24df4d075c319ebfc5@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in usb_autopm_put_interface+0x70/0x90  
drivers/usb/core/driver.c:1629
Read of size 8 at addr ffff8881d8cdf070 by task syz-executor117/2705

CPU: 1 PID: 2705 Comm: syz-executor117 Not tainted 5.4.0-rc3+ #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+0xca/0x13e lib/dump_stack.c:113
  print_address_description.constprop.0+0x36/0x50 mm/kasan/report.c:374
  __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:506
  kasan_report+0xe/0x20 mm/kasan/common.c:634
  usb_autopm_put_interface+0x70/0x90 drivers/usb/core/driver.c:1629
  usblp_release+0x121/0x1d0 drivers/usb/class/usblp.c:467
  __fput+0x2d7/0x840 fs/file_table.c:280
  task_work_run+0x13f/0x1c0 kernel/task_work.c:113
  exit_task_work include/linux/task_work.h:22 [inline]
  do_exit+0x8c4/0x2c00 kernel/exit.c:817
  do_group_exit+0x125/0x340 kernel/exit.c:921
  get_signal+0x466/0x23d0 kernel/signal.c:2734
  do_signal+0x88/0x14e0 arch/x86/kernel/signal.c:815
  exit_to_usermode_loop+0x1a2/0x200 arch/x86/entry/common.c:159
  prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
  syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
  do_syscall_64+0x45f/0x580 arch/x86/entry/common.c:300
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x448569
Code: Bad RIP value.
RSP: 002b:00007fcc286a6db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00000000006ddc48 RCX: 0000000000448569
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006ddc48
RBP: 00000000006ddc40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006ddc4c
R13: 00007fff5babd83f R14: 00007fcc286a79c0 R15: 00000000006ddc4c

Allocated by task 102:
  save_stack+0x1b/0x80 mm/kasan/common.c:69
  set_track mm/kasan/common.c:77 [inline]
  __kasan_kmalloc mm/kasan/common.c:510 [inline]
  __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:483
  kmalloc include/linux/slab.h:556 [inline]
  kzalloc include/linux/slab.h:690 [inline]
  usb_set_configuration+0x2c4/0x1670 drivers/usb/core/message.c:1846
  generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210
  usb_probe_device+0x99/0x100 drivers/usb/core/driver.c:266
  really_probe+0x281/0x6d0 drivers/base/dd.c:548
  driver_probe_device+0x104/0x210 drivers/base/dd.c:721
  __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
  bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430
  __device_attach+0x217/0x360 drivers/base/dd.c:894
  bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490
  device_add+0xae6/0x16f0 drivers/base/core.c:2201
  usb_new_device.cold+0x6a4/0xe79 drivers/usb/core/hub.c:2536
  hub_port_connect drivers/usb/core/hub.c:5183 [inline]
  hub_port_connect_change drivers/usb/core/hub.c:5323 [inline]
  port_event drivers/usb/core/hub.c:5469 [inline]
  hub_event+0x1dd0/0x37e0 drivers/usb/core/hub.c:5551
  process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
  worker_thread+0x96/0xe20 kernel/workqueue.c:2415
  kthread+0x318/0x420 kernel/kthread.c:255
  ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Freed by task 102:
  save_stack+0x1b/0x80 mm/kasan/common.c:69
  set_track mm/kasan/common.c:77 [inline]
  kasan_set_free_info mm/kasan/common.c:332 [inline]
  __kasan_slab_free+0x130/0x180 mm/kasan/common.c:471
  slab_free_hook mm/slub.c:1424 [inline]
  slab_free_freelist_hook mm/slub.c:1475 [inline]
  slab_free mm/slub.c:3018 [inline]
  kfree+0xe4/0x320 mm/slub.c:3967
  device_release+0x71/0x200 drivers/base/core.c:1100
  kobject_cleanup lib/kobject.c:693 [inline]
  kobject_release lib/kobject.c:722 [inline]
  kref_put include/linux/kref.h:65 [inline]
  kobject_put+0x171/0x280 lib/kobject.c:739
  put_device+0x1b/0x30 drivers/base/core.c:2300
  usb_disable_device+0x2ce/0x690 drivers/usb/core/message.c:1244
  usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2199
  hub_port_connect drivers/usb/core/hub.c:5034 [inline]
  hub_port_connect_change drivers/usb/core/hub.c:5323 [inline]
  port_event drivers/usb/core/hub.c:5469 [inline]
  hub_event+0x16ca/0x37e0 drivers/usb/core/hub.c:5551
  process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
  process_scheduled_works kernel/workqueue.c:2331 [inline]
  worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
  kthread+0x318/0x420 kernel/kthread.c:255
  ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

The buggy address belongs to the object at ffff8881d8cdf000
  which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 112 bytes inside of
  2048-byte region [ffff8881d8cdf000, ffff8881d8cdf800)
The buggy address belongs to the page:
page:ffffea0007633600 refcount:1 mapcount:0 mapping:ffff8881da00c000  
index:0x0 compound_mapcount: 0
flags: 0x200000000010200(slab|head)
raw: 0200000000010200 0000000000000000 0000000100000001 ffff8881da00c000
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
  ffff8881d8cdef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
  ffff8881d8cdef80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ffff8881d8cdf000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                              ^
  ffff8881d8cdf080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff8881d8cdf100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
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#status for how to communicate with syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches

^ permalink raw reply	[flat|nested] 2+ messages in thread
* [PATCH] USB: usblp: fix use-after-free on disconnect
  2019-10-15 15:51 KASAN: use-after-free Read in usb_autopm_put_interface syzbot
@ 2019-10-15 17:55 ` Johan Hovold
  0 siblings, 0 replies; 2+ messages in thread
From: Johan Hovold @ 2019-10-15 17:55 UTC (permalink / raw)
  To: Greg Kroah-Hartman
  Cc: linux-usb, linux-kernel, Pete Zaitcev, Johan Hovold, stable,
	syzbot+cd24df4d075c319ebfc5

A recent commit addressing a runtime PM use-count regression, introduced
a use-after-free by not making sure we held a reference to the struct
usb_interface for the lifetime of the driver data.

Fixes: 9a31535859bf ("USB: usblp: fix runtime PM after driver unbind")
Cc: stable <stable@vger.kernel.org>
Reported-by: syzbot+cd24df4d075c319ebfc5@syzkaller.appspotmail.com
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/usb/class/usblp.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/class/usblp.c b/drivers/usb/class/usblp.c
index fb8bd60c83f4..0d8e3f3804a3 100644
--- a/drivers/usb/class/usblp.c
+++ b/drivers/usb/class/usblp.c
@@ -445,6 +445,7 @@ static void usblp_cleanup(struct usblp *usblp)
 	kfree(usblp->readbuf);
 	kfree(usblp->device_id_string);
 	kfree(usblp->statusbuf);
+	usb_put_intf(usblp->intf);
 	kfree(usblp);
 }
 
@@ -1113,7 +1114,7 @@ static int usblp_probe(struct usb_interface *intf,
 	init_waitqueue_head(&usblp->wwait);
 	init_usb_anchor(&usblp->urbs);
 	usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
-	usblp->intf = intf;
+	usblp->intf = usb_get_intf(intf);
 
 	/* Malloc device ID string buffer to the largest expected length,
 	 * since we can re-query it on an ioctl and a dynamic string
@@ -1198,6 +1199,7 @@ static int usblp_probe(struct usb_interface *intf,
 	kfree(usblp->readbuf);
 	kfree(usblp->statusbuf);
 	kfree(usblp->device_id_string);
+	usb_put_intf(usblp->intf);
 	kfree(usblp);
 abort_ret:
 	return retval;
-- 
2.23.0


^ permalink raw reply related	[flat|nested] 2+ messages in thread
end of thread, other threads:[~2019-10-15 17:55 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-10-15 15:51 KASAN: use-after-free Read in usb_autopm_put_interface syzbot
2019-10-15 17:55 ` [PATCH] USB: usblp: fix use-after-free on disconnect Johan Hovold

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).