diff mbox

[V3] mt7601u: do not free dma_buf when ivp allocation fails

Message ID 1456442667-19751-1-git-send-email-colin.king@canonical.com (mailing list archive)
State New, archived
Headers show

Commit Message

Colin King Feb. 25, 2016, 11:24 p.m. UTC
From: Colin Ian King <colin.king@canonical.com>

If the allocation of ivp fails the error handling attempts to
free an uninitialized dma_buf; this data structure just contains
garbage on the stack, so the freeing will cause issues when the
urb, buf and dma fields are free'd. Fix this by not free'ing the
dma_buf if the ivp allocation fails.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 drivers/net/wireless/mediatek/mt7601u/mcu.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Julian Calaby Feb. 25, 2016, 11:31 p.m. UTC | #1
Hi,

On Fri, Feb 26, 2016 at 10:24 AM, Colin King <colin.king@canonical.com> wrote:
> From: Colin Ian King <colin.king@canonical.com>
>
> If the allocation of ivp fails the error handling attempts to
> free an uninitialized dma_buf; this data structure just contains
> garbage on the stack, so the freeing will cause issues when the
> urb, buf and dma fields are free'd. Fix this by not free'ing the
> dma_buf if the ivp allocation fails.
>
> Signed-off-by: Colin Ian King <colin.king@canonical.com>

Looks right to me.

Reviewed-by: Julian Calaby <julian.calaby@gmail.com>

> ---
>  drivers/net/wireless/mediatek/mt7601u/mcu.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/mediatek/mt7601u/mcu.c b/drivers/net/wireless/mediatek/mt7601u/mcu.c
> index fbb1986..91c4b34 100644
> --- a/drivers/net/wireless/mediatek/mt7601u/mcu.c
> +++ b/drivers/net/wireless/mediatek/mt7601u/mcu.c
> @@ -362,7 +362,9 @@ mt7601u_upload_firmware(struct mt7601u_dev *dev, const struct mt76_fw *fw)
>         int i, ret;
>
>         ivb = kmemdup(fw->ivb, sizeof(fw->ivb), GFP_KERNEL);
> -       if (!ivb || mt7601u_usb_alloc_buf(dev, MCU_FW_URB_SIZE, &dma_buf)) {
> +       if (!ivb)
> +               return -ENOMEM;
> +       if (mt7601u_usb_alloc_buf(dev, MCU_FW_URB_SIZE, &dma_buf)) {
>                 ret = -ENOMEM;
>                 goto error;
>         }
> --
> 2.7.0
>
> --
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Thanks,
Jakub Kicinski Feb. 25, 2016, 11:36 p.m. UTC | #2
On 25 February 2016 18:24:27 GMT-05:00, Colin King <colin.king@canonical.com> wrote:
>From: Colin Ian King <colin.king@canonical.com>
>
>If the allocation of ivp fails the error handling attempts to
>free an uninitialized dma_buf; this data structure just contains
>garbage on the stack, so the freeing will cause issues when the
>urb, buf and dma fields are free'd. Fix this by not free'ing the
>dma_buf if the ivp allocation fails.
>
>Signed-off-by: Colin Ian King <colin.king@canonical.com>

LGTM, thanks.
Kalle Valo March 7, 2016, 12:39 p.m. UTC | #3
> From: Colin Ian King <colin.king@canonical.com>
> 
> If the allocation of ivp fails the error handling attempts to
> free an uninitialized dma_buf; this data structure just contains
> garbage on the stack, so the freeing will cause issues when the
> urb, buf and dma fields are free'd. Fix this by not free'ing the
> dma_buf if the ivp allocation fails.
> 
> Signed-off-by: Colin Ian King <colin.king@canonical.com>
> Reviewed-by: Julian Calaby <julian.calaby@gmail.com>

Thanks, applied to wireless-drivers-next.git.

Kalle Valo
diff mbox

Patch

diff --git a/drivers/net/wireless/mediatek/mt7601u/mcu.c b/drivers/net/wireless/mediatek/mt7601u/mcu.c
index fbb1986..91c4b34 100644
--- a/drivers/net/wireless/mediatek/mt7601u/mcu.c
+++ b/drivers/net/wireless/mediatek/mt7601u/mcu.c
@@ -362,7 +362,9 @@  mt7601u_upload_firmware(struct mt7601u_dev *dev, const struct mt76_fw *fw)
 	int i, ret;
 
 	ivb = kmemdup(fw->ivb, sizeof(fw->ivb), GFP_KERNEL);
-	if (!ivb || mt7601u_usb_alloc_buf(dev, MCU_FW_URB_SIZE, &dma_buf)) {
+	if (!ivb)
+		return -ENOMEM;
+	if (mt7601u_usb_alloc_buf(dev, MCU_FW_URB_SIZE, &dma_buf)) {
 		ret = -ENOMEM;
 		goto error;
 	}