From: Marc Kleine-Budde <mkl@pengutronix.de>
To: Rhett Aultman <rhett.aultman@samsara.com>
Cc: linux-usb@vger.kernel.org, linux-can <linux-can@vger.kernel.org>,
Oliver Neukum <oneukum@suse.com>,
Alan Stern <stern@rowland.harvard.edu>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Subject: Re: [PATCH v3 2/2] can: gs_usb: fix DMA memory leak on close
Date: Sat, 11 Jun 2022 17:35:43 +0200 [thread overview]
Message-ID: <20220611153543.s5enriuu7jcllz3t@pengutronix.de> (raw)
In-Reply-To: <20220610213335.3077375-3-rhett.aultman@samsara.com>
[-- Attachment #1: Type: text/plain, Size: 1279 bytes --]
On 10.06.2022 17:33:37, Rhett Aultman wrote:
> The gs_usb driver allocates DMA memory with usb_alloc_coherent() in
> gs_can_open() and then keeps this memory in an URB, with the expectation
> that the memory will be freed when the URB is killed in gs_can_close().
> Memory allocated with usb_alloc_coherent() cannot be freed in this way
> and must be freed using usb_free_coherent() instead. This means that
> repeated cycles of calling gs_can_open() and gs_can_close() will lead to
> a memory leak.
>
> Historically, drivers have handled this by keeping an array of pointers
> to their DMA rx buffers and explicitly freeing them. For an example of
> this technique used in the esd_usb2 driver, see here:
> https://www.spinics.net/lists/linux-can/msg08203.html
Better reference the commit or use a link to lore.kernel.org:
928150fad41b ("can: esd_usb2: fix memory leak")
https://lore.kernel.org/all/b31b096926dcb35998ad0271aac4b51770ca7cc8.1627404470.git.paskripkin@gmail.com/
Marc
--
Pengutronix e.K. | Marc Kleine-Budde |
Embedded Linux | https://www.pengutronix.de |
Vertretung West/Dortmund | Phone: +49-231-2826-924 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 488 bytes --]
next prev parent reply other threads:[~2022-06-11 15:35 UTC|newest]
Thread overview: 72+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-03 19:52 [PATCH 001/001] can: gs_usb: gs_usb_open/close( ) fix memory leak Rhett Aultman
2022-06-04 2:11 ` [PATCH] " Vincent Mailhol
2022-06-04 2:26 ` Vincent MAILHOL
2022-06-04 14:08 ` Rhett Aultman
2022-06-04 14:41 ` [RFC PATCH] USB: core: urb: add new transfer flag URB_FREE_COHERENT Vincent Mailhol
2022-06-04 16:40 ` Alan Stern
2022-06-05 2:04 ` Vincent MAILHOL
2022-06-05 6:00 ` Oliver Neukum
2022-06-05 13:45 ` Vincent MAILHOL
2022-06-07 9:49 ` Oliver Neukum
2022-06-07 10:18 ` Vincent MAILHOL
2022-06-07 11:46 ` Oliver Neukum
2022-06-07 12:12 ` Vincent MAILHOL
2022-06-05 2:15 ` [RFC PATCH v2] usb: " Vincent Mailhol
2022-06-04 14:53 ` [PATCH] can: gs_usb: gs_usb_open/close( ) fix memory leak Vincent MAILHOL
2022-06-09 20:47 ` [PATCH v2 0/3] URB_FREE_COHERENT gs_usb memory leak fix Rhett Aultman
2022-06-09 20:47 ` [PATCH v2 1/3] drivers: usb/core/urb: Add URB_FREE_COHERENT Rhett Aultman
2022-06-10 0:18 ` Vincent MAILHOL
2022-06-10 10:46 ` Marc Kleine-Budde
2022-06-09 20:47 ` [PATCH v2 2/3] drivers: usb/core/urb: allow URB_FREE_COHERENT Rhett Aultman
2022-06-09 23:18 ` Vincent Mailhol
2022-06-09 20:47 ` [PATCH v2 3/3] can: gs_usb: fix DMA memory leak on close Rhett Aultman
2022-06-10 0:05 ` Vincent Mailhol
2022-06-10 1:28 ` Vincent Mailhol
2022-06-10 21:33 ` [PATCH v3 0/2] URB_FREE_COHERENT gs_usb memory leak fix Rhett Aultman
2022-06-10 21:33 ` [PATCH v3 1/2] drivers: usb/core/urb: Add URB_FREE_COHERENT Rhett Aultman
2022-06-11 15:31 ` Marc Kleine-Budde
2022-06-11 16:06 ` Vincent MAILHOL
2022-06-21 13:51 ` Greg Kroah-Hartman
2022-06-21 14:59 ` Vincent MAILHOL
2022-06-21 15:03 ` Greg Kroah-Hartman
2022-06-21 15:54 ` Vincent MAILHOL
2022-06-21 15:11 ` Alan Stern
2022-06-21 15:55 ` Vincent MAILHOL
2022-06-21 16:14 ` Alan Stern
2022-06-21 16:40 ` Vincent MAILHOL
2022-06-21 17:00 ` Greg Kroah-Hartman
2022-06-21 17:14 ` Vincent MAILHOL
2022-06-21 17:46 ` Greg Kroah-Hartman
2022-06-22 9:22 ` David Laight
2022-06-22 9:41 ` Greg Kroah-Hartman
2022-06-22 10:03 ` David Laight
2022-06-22 11:11 ` Oliver Neukum
2022-06-22 10:34 ` Vincent MAILHOL
2022-06-22 12:23 ` Greg Kroah-Hartman
2022-06-22 15:59 ` Vincent MAILHOL
2022-06-22 18:11 ` Rhett Aultman
2022-06-26 8:21 ` Vincent MAILHOL
2022-06-27 19:24 ` Rhett Aultman
2022-06-28 1:09 ` Vincent MAILHOL
2022-07-04 13:02 ` Marc Kleine-Budde
2022-07-04 15:35 ` Rhett Aultman
2022-07-05 7:50 ` Marc Kleine-Budde
2022-06-23 17:30 ` Hongren Zenithal Zheng
2022-06-23 17:45 ` Shuah Khan
2022-06-24 14:43 ` Alan Stern
2022-06-24 16:01 ` Hongren Zenithal Zheng
2022-06-24 16:31 ` Shuah Khan
2022-06-24 18:07 ` Alan Stern
2022-06-27 22:54 ` Shuah Khan
2022-06-28 1:35 ` Alan Stern
2022-07-01 2:10 ` Shuah Khan
2022-08-01 17:42 ` Shuah Khan
2022-08-01 18:28 ` Vincent MAILHOL
2022-08-03 23:44 ` Shuah Khan
2022-06-10 21:33 ` [PATCH v3 2/2] can: gs_usb: fix DMA memory leak on close Rhett Aultman
2022-06-11 15:35 ` Marc Kleine-Budde [this message]
2022-06-11 16:03 ` Vincent MAILHOL
2022-06-12 21:28 ` David Laight
2022-06-12 21:33 ` Marc Kleine-Budde
2022-06-14 15:26 ` [PATCH v4 0/1] URB_FREE_COHERENT gs_usb memory leak fix Rhett Aultman
2022-06-14 15:26 ` [PATCH v4 1/1] can: gs_usb: fix DMA memory leak on close Rhett Aultman
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=20220611153543.s5enriuu7jcllz3t@pengutronix.de \
--to=mkl@pengutronix.de \
--cc=gregkh@linuxfoundation.org \
--cc=linux-can@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=mailhol.vincent@wanadoo.fr \
--cc=oneukum@suse.com \
--cc=rhett.aultman@samsara.com \
--cc=stern@rowland.harvard.edu \
/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 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).