All of lore.kernel.org
 help / color / mirror / Atom feed
From: Sean Young <sean@mess.org>
To: linux-media@vger.kernel.org
Cc: stable@vger.kernel.org
Subject: [PATCH] media: tm6000: double free if usb disconnect while streaming
Date: Tue, 13 Aug 2019 21:14:39 +0100	[thread overview]
Message-ID: <20190813201439.22480-1-sean@mess.org> (raw)

The usb_bulk_urb will kfree'd on disconnect, so ensure the pointer is set
to NULL after each free.

stop stream
urb killing
urb buffer free
tm6000: got start feed request tm6000_start_feed
tm6000: got start stream request tm6000_start_stream
tm6000: pipe reset
tm6000: got start feed request tm6000_start_feed
tm6000: got start feed request tm6000_start_feed
tm6000: got start feed request tm6000_start_feed
tm6000: got start feed request tm6000_start_feed
tm6000: IR URB failure: status: -71, length 0
xhci_hcd 0000:00:14.0: ERROR unknown event type 37
xhci_hcd 0000:00:14.0: ERROR unknown event type 37
tm6000:  error tm6000_urb_received
usb 1-2: USB disconnect, device number 5
tm6000: disconnecting tm6000 #0
==================================================================
BUG: KASAN: use-after-free in dvb_fini+0x75/0x140 [tm6000_dvb]
Read of size 8 at addr ffff888241044060 by task kworker/2:0/22

CPU: 2 PID: 22 Comm: kworker/2:0 Tainted: G        W         5.3.0-rc4+ #1
Hardware name: LENOVO 20KHCTO1WW/20KHCTO1WW, BIOS N23ET65W (1.40 ) 07/02/2019
Workqueue: usb_hub_wq hub_event
Call Trace:
 dump_stack+0x9a/0xf0
 print_address_description.cold+0xae/0x34f
 __kasan_report.cold+0x75/0x93
 ? tm6000_fillbuf+0x390/0x3c0 [tm6000_alsa]
 ? dvb_fini+0x75/0x140 [tm6000_dvb]
 kasan_report+0xe/0x12
 dvb_fini+0x75/0x140 [tm6000_dvb]
 tm6000_close_extension+0x51/0x80 [tm6000]
 tm6000_usb_disconnect.cold+0xd4/0x105 [tm6000]
 usb_unbind_interface+0xe4/0x390
 device_release_driver_internal+0x121/0x250
 bus_remove_device+0x197/0x260
 device_del+0x268/0x550
 ? __device_links_no_driver+0xd0/0xd0
 ? usb_remove_ep_devs+0x30/0x3b
 usb_disable_device+0x122/0x400
 usb_disconnect+0x153/0x430
 hub_event+0x800/0x1e40
 ? trace_hardirqs_on_thunk+0x1a/0x20
 ? hub_port_debounce+0x1f0/0x1f0
 ? retint_kernel+0x10/0x10
 ? lock_is_held_type+0xf1/0x130
 ? hub_port_debounce+0x1f0/0x1f0
 ? process_one_work+0x4ae/0xa00
 process_one_work+0x4ba/0xa00
 ? pwq_dec_nr_in_flight+0x160/0x160
 ? do_raw_spin_lock+0x10a/0x1d0
 worker_thread+0x7a/0x5c0
 ? process_one_work+0xa00/0xa00
 kthread+0x1d5/0x200
 ? kthread_create_worker_on_cpu+0xd0/0xd0
 ret_from_fork+0x3a/0x50

Allocated by task 2682:
 save_stack+0x1b/0x80
 __kasan_kmalloc.constprop.0+0xc2/0xd0
 usb_alloc_urb+0x28/0x60
 tm6000_start_feed+0x10a/0x300 [tm6000_dvb]
 dmx_ts_feed_start_filtering+0x86/0x120 [dvb_core]
 dvb_dmxdev_start_feed+0x121/0x180 [dvb_core]
 dvb_dmxdev_filter_start+0xcb/0x540 [dvb_core]
 dvb_demux_do_ioctl+0x7ed/0x890 [dvb_core]
 dvb_usercopy+0x97/0x1f0 [dvb_core]
 dvb_demux_ioctl+0x11/0x20 [dvb_core]
 do_vfs_ioctl+0x5d8/0x9d0
 ksys_ioctl+0x5e/0x90
 __x64_sys_ioctl+0x3d/0x50
 do_syscall_64+0x74/0xe0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 22:
 save_stack+0x1b/0x80
 __kasan_slab_free+0x12c/0x170
 kfree+0xfd/0x3a0
 xhci_giveback_urb_in_irq+0xfe/0x230
 xhci_td_cleanup+0x276/0x340
 xhci_irq+0x1129/0x3720
 __handle_irq_event_percpu+0x6e/0x420
 handle_irq_event_percpu+0x6f/0x100
 handle_irq_event+0x55/0x84
 handle_edge_irq+0x108/0x3b0
 handle_irq+0x2e/0x40
 do_IRQ+0x83/0x1a0

Cc: stable@vger.kernel.org
Signed-off-by: Sean Young <sean@mess.org>
---
 drivers/media/usb/tm6000/tm6000-dvb.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/media/usb/tm6000/tm6000-dvb.c b/drivers/media/usb/tm6000/tm6000-dvb.c
index e4d2dcd5cc0f..19c90fa9e443 100644
--- a/drivers/media/usb/tm6000/tm6000-dvb.c
+++ b/drivers/media/usb/tm6000/tm6000-dvb.c
@@ -97,6 +97,7 @@ static void tm6000_urb_received(struct urb *urb)
 			printk(KERN_ERR "tm6000:  error %s\n", __func__);
 			kfree(urb->transfer_buffer);
 			usb_free_urb(urb);
+			dev->dvb->bulk_urb = NULL;
 		}
 	}
 }
@@ -127,6 +128,7 @@ static int tm6000_start_stream(struct tm6000_core *dev)
 	dvb->bulk_urb->transfer_buffer = kzalloc(size, GFP_KERNEL);
 	if (!dvb->bulk_urb->transfer_buffer) {
 		usb_free_urb(dvb->bulk_urb);
+		dvb->bulk_urb = NULL;
 		return -ENOMEM;
 	}
 
@@ -153,6 +155,7 @@ static int tm6000_start_stream(struct tm6000_core *dev)
 
 		kfree(dvb->bulk_urb->transfer_buffer);
 		usb_free_urb(dvb->bulk_urb);
+		dvb->bulk_urb = NULL;
 		return ret;
 	}
 
-- 
2.21.0


             reply	other threads:[~2019-08-13 20:14 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-13 20:14 Sean Young [this message]
2019-08-14  1:01 ` [PATCH] media: tm6000: double free if usb disconnect while streaming Sasha Levin

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=20190813201439.22480-1-sean@mess.org \
    --to=sean@mess.org \
    --cc=linux-media@vger.kernel.org \
    --cc=stable@vger.kernel.org \
    /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.