2014-11-13 02:33:33

by Mathy Vanhoef

Subject: [PATCH] brcmfmac: kill URB when request timed out

Kill the submitted URB in brcmf_usb_dl_cmd if the request timed out. This
assures the URB is never submitted twice. It also prevents a possible
use-after-free of the URB transfer buffer if a timeout occurs.

Signed-off-by: Mathy Vanhoef <[email protected]>
---
For a discussion about this patch and the underlying problem, see the mails
with as subject "[PATCH] brcmfmac: unlink URB when request timed out".

drivers/net/wireless/brcm80211/brcmfmac/usb.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/brcm80211/brcmfmac/usb.c b/drivers/net/wireless/brcm80211/brcmfmac/usb.c
index 5265aa7..4572def 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/usb.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/usb.c
@@ -738,10 +738,12 @@ static int brcmf_usb_dl_cmd(struct brcmf_usbdev_info *devinfo, u8 cmd,
goto finalize;
}

- if (!brcmf_usb_ioctl_resp_wait(devinfo))
+ if (!brcmf_usb_ioctl_resp_wait(devinfo)) {
+ usb_kill_urb(devinfo->ctl_urb);
ret = -ETIMEDOUT;
- else
+ } else {
memcpy(buffer, tmpbuf, buflen);
+ }

finalize:
kfree(tmpbuf);
--
1.7.10.4

2014-11-14 08:57:09

by Arend van Spriel

Subject: Re: [PATCH] brcmfmac: kill URB when request timed out

On 13-11-14 03:33, Mathy Vanhoef wrote:
> Kill the submitted URB in brcmf_usb_dl_cmd if the request timed out. This
> assures the URB is never submitted twice. It also prevents a possible
> use-after-free of the URB transfer buffer if a timeout occurs.
>
Acked-by: Arend van Spriel <[email protected]>
> Signed-off-by: Mathy Vanhoef <[email protected]>
> ---
> For a discussion about this patch and the underlying problem, see the mails
> with as subject "[PATCH] brcmfmac: unlink URB when request timed out".
>
> drivers/net/wireless/brcm80211/brcmfmac/usb.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/wireless/brcm80211/brcmfmac/usb.c b/drivers/net/wireless/brcm80211/brcmfmac/usb.c
> index 5265aa7..4572def 100644
> --- a/drivers/net/wireless/brcm80211/brcmfmac/usb.c
> +++ b/drivers/net/wireless/brcm80211/brcmfmac/usb.c
> @@ -738,10 +738,12 @@ static int brcmf_usb_dl_cmd(struct brcmf_usbdev_info *devinfo, u8 cmd,
> goto finalize;
> }
>
> - if (!brcmf_usb_ioctl_resp_wait(devinfo))
> + if (!brcmf_usb_ioctl_resp_wait(devinfo)) {
> + usb_kill_urb(devinfo->ctl_urb);
> ret = -ETIMEDOUT;
> - else
> + } else {
> memcpy(buffer, tmpbuf, buflen);
> + }
>
> finalize:
> kfree(tmpbuf);
>