* [BUG] usb: serial: garmin_gps: A possible concurrency use-after-free bug
@ 2018-12-20 13:41 Jia-Ju Bai
2018-12-20 13:46 ` Johan Hovold
0 siblings, 1 reply; 3+ messages in thread
From: Jia-Ju Bai @ 2018-12-20 13:41 UTC (permalink / raw)
To: Johan Hovold, Greg KH; +Cc: linux-usb, Linux Kernel Mailing List
In drivers/usb/serial/garmin_gps.c,
the functions garmin_read_bulk_callback() and garmin_write_bulk_callback()
may be concurrently executed.
In garmin_write_bulk_callback() on line 969:
kfree(urb->transfer_buffer);
In garmin_read_bulk_callback() on line 1165:
unsigned char *data = urb->transfer_buffer;
Thus, a concurrency use-after-free bug may occur.
This possible bug is found by a static analysis tool written by myself.
Best wishes,
Jia-Ju Bai
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: [BUG] usb: serial: garmin_gps: A possible concurrency use-after-free bug
2018-12-20 13:41 [BUG] usb: serial: garmin_gps: A possible concurrency use-after-free bug Jia-Ju Bai
@ 2018-12-20 13:46 ` Johan Hovold
2018-12-20 13:48 ` Jia-Ju Bai
0 siblings, 1 reply; 3+ messages in thread
From: Johan Hovold @ 2018-12-20 13:46 UTC (permalink / raw)
To: Jia-Ju Bai; +Cc: Johan Hovold, Greg KH, linux-usb, Linux Kernel Mailing List
On Thu, Dec 20, 2018 at 09:41:16PM +0800, Jia-Ju Bai wrote:
> In drivers/usb/serial/garmin_gps.c,
> the functions garmin_read_bulk_callback() and garmin_write_bulk_callback()
> may be concurrently executed.
>
> In garmin_write_bulk_callback() on line 969:
> kfree(urb->transfer_buffer);
> In garmin_read_bulk_callback() on line 1165:
> unsigned char *data = urb->transfer_buffer;
> Thus, a concurrency use-after-free bug may occur.
No, they operate on different struct urb.
> This possible bug is found by a static analysis tool written by myself.
Seems you need to update your tool. Please also make sure to review its
output before reporting anything.
Thanks,
Johan
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [BUG] usb: serial: garmin_gps: A possible concurrency use-after-free bug
2018-12-20 13:46 ` Johan Hovold
@ 2018-12-20 13:48 ` Jia-Ju Bai
0 siblings, 0 replies; 3+ messages in thread
From: Jia-Ju Bai @ 2018-12-20 13:48 UTC (permalink / raw)
To: Johan Hovold; +Cc: Greg KH, linux-usb, Linux Kernel Mailing List
On 2018/12/20 21:46, Johan Hovold wrote:
> On Thu, Dec 20, 2018 at 09:41:16PM +0800, Jia-Ju Bai wrote:
>> In drivers/usb/serial/garmin_gps.c,
>> the functions garmin_read_bulk_callback() and garmin_write_bulk_callback()
>> may be concurrently executed.
>>
>> In garmin_write_bulk_callback() on line 969:
>> kfree(urb->transfer_buffer);
>> In garmin_read_bulk_callback() on line 1165:
>> unsigned char *data = urb->transfer_buffer;
>> Thus, a concurrency use-after-free bug may occur.
> No, they operate on different struct urb.
>
>> This possible bug is found by a static analysis tool written by myself.
> Seems you need to update your tool. Please also make sure to review its
> output before reporting anything.
Okay, thanks for your reply.
Sorry for my false positive...
Best wishes,
Jia-Ju Bai
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2018-12-20 13:48 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2018-12-20 13:41 [BUG] usb: serial: garmin_gps: A possible concurrency use-after-free bug Jia-Ju Bai
2018-12-20 13:46 ` Johan Hovold
2018-12-20 13:48 ` Jia-Ju Bai
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox