From: Alan Stern <stern@rowland.harvard.edu>
To: Niklas Neronin <niklas.neronin@linux.intel.com>
Cc: linux-usb@vger.kernel.org, gregkh@linuxfoundation.org,
stable@vger.kernel.org
Subject: Re: [PATCH] usb: config: fix iteration issue in 'usb_get_bos_descriptor()'
Date: Fri, 17 Nov 2023 10:50:39 -0500 [thread overview]
Message-ID: <c9df94db-c810-4f8c-846f-dc2e83fd327c@rowland.harvard.edu> (raw)
In-Reply-To: <20231115121325.471454-1-niklas.neronin@linux.intel.com>
On Wed, Nov 15, 2023 at 02:13:25PM +0200, Niklas Neronin wrote:
> The BOS descriptor defines a root descriptor and is the base descriptor for
> accessing a family of related descriptors.
>
> Function 'usb_get_bos_descriptor()' encounters an iteration issue when
> skipping the 'USB_DT_DEVICE_CAPABILITY' descriptor type. This results in
> the same descriptor being read repeatedly.
>
> To address this issue, a 'goto' statement is introduced to ensure that the
> pointer and the amount read is updated correctly. This ensures that the
> function iterates to the next descriptor instead of reading the same
> descriptor repeatedly.
>
> Cc: stable@vger.kernel.org
> Fixes: 3dd550a2d365 ("USB: usbcore: Fix slab-out-of-bounds bug during device reset")
> Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
> ---
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Don't know how I missed that four years ago...
> drivers/usb/core/config.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
> index b19e38d5fd10..7f8d33f92ddb 100644
> --- a/drivers/usb/core/config.c
> +++ b/drivers/usb/core/config.c
> @@ -1047,7 +1047,7 @@ int usb_get_bos_descriptor(struct usb_device *dev)
>
> if (cap->bDescriptorType != USB_DT_DEVICE_CAPABILITY) {
> dev_notice(ddev, "descriptor type invalid, skip\n");
> - continue;
> + goto skip_to_next_descriptor;
> }
>
> switch (cap_type) {
> @@ -1078,6 +1078,7 @@ int usb_get_bos_descriptor(struct usb_device *dev)
> break;
> }
>
> +skip_to_next_descriptor:
> total_len -= length;
> buffer += length;
> }
> --
> 2.42.0
>
prev parent reply other threads:[~2023-11-17 15:50 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-11-15 12:13 [PATCH] usb: config: fix iteration issue in 'usb_get_bos_descriptor()' Niklas Neronin
2023-11-17 13:50 ` Mathias Nyman
2023-11-17 15:50 ` Alan Stern [this message]
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=c9df94db-c810-4f8c-846f-dc2e83fd327c@rowland.harvard.edu \
--to=stern@rowland.harvard.edu \
--cc=gregkh@linuxfoundation.org \
--cc=linux-usb@vger.kernel.org \
--cc=niklas.neronin@linux.intel.com \
--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.