| Message ID | 1394226709-10763-1-git-send-email-khoroshilov@ispras.ru (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Saturday, March 08, 2014 01:11:49 AM Alexey Khoroshilov wrote: > If p54u_load_firmware() fails, p54u_probe() does not deallocate > already allocated resources. The patch adds proper failure handling. > > Found by Linux Driver Verification project (linuxtesting.org). > > Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Acked-by: Christian Lamparter <chunkeey@googlemail.com> -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sat, Mar 8, 2014 at 2:41 AM, Alexey Khoroshilov <khoroshilov@ispras.ru> wrote: > If p54u_load_firmware() fails, p54u_probe() does not deallocate > already allocated resources. The patch adds proper failure handling. > > Found by Linux Driver Verification project (linuxtesting.org). > > Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> > --- > drivers/net/wireless/p54/p54usb.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/drivers/net/wireless/p54/p54usb.c b/drivers/net/wireless/p54/p54usb.c > index 6e635cfa24c8..5df74503fd4f 100644 > --- a/drivers/net/wireless/p54/p54usb.c > +++ b/drivers/net/wireless/p54/p54usb.c > @@ -1053,6 +1053,10 @@ static int p54u_probe(struct usb_interface *intf, > priv->upload_fw = p54u_upload_firmware_net2280; > } > err = p54u_load_firmware(dev, intf); > + if (err) { > + usb_put_dev(udev); > + p54_free_common(dev); > + } > return err; > } The load_firmware puts down the reference in case of error. Only free is required here. -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 09.03.2014 02:44, Krishna Chaitanya wrote: > On Sat, Mar 8, 2014 at 2:41 AM, Alexey Khoroshilov > <khoroshilov@ispras.ru> wrote: >> If p54u_load_firmware() fails, p54u_probe() does not deallocate >> already allocated resources. The patch adds proper failure handling. >> >> Found by Linux Driver Verification project (linuxtesting.org). >> >> Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> >> --- >> drivers/net/wireless/p54/p54usb.c | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/drivers/net/wireless/p54/p54usb.c b/drivers/net/wireless/p54/p54usb.c >> index 6e635cfa24c8..5df74503fd4f 100644 >> --- a/drivers/net/wireless/p54/p54usb.c >> +++ b/drivers/net/wireless/p54/p54usb.c >> @@ -1053,6 +1053,10 @@ static int p54u_probe(struct usb_interface *intf, >> priv->upload_fw = p54u_upload_firmware_net2280; >> } >> err = p54u_load_firmware(dev, intf); >> + if (err) { >> + usb_put_dev(udev); >> + p54_free_common(dev); >> + } >> return err; >> } > The load_firmware puts down the reference > in case of error. Only free is required here. No, p54u_load_firmware() puts down reference that was got up by itself. So we still have to put down reference got up in p54u_probe(). -- Alexey -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sunday, March 09, 2014 04:14:32 AM Krishna Chaitanya wrote: > On Sat, Mar 8, 2014 at 2:41 AM, Alexey Khoroshilov > <khoroshilov@ispras.ru> wrote: > > If p54u_load_firmware() fails, p54u_probe() does not deallocate > > already allocated resources. The patch adds proper failure handling. > > > > Found by Linux Driver Verification project (linuxtesting.org). > > > > Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> > > --- > > drivers/net/wireless/p54/p54usb.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/drivers/net/wireless/p54/p54usb.c b/drivers/net/wireless/p54/p54usb.c > > index 6e635cfa24c8..5df74503fd4f 100644 > > --- a/drivers/net/wireless/p54/p54usb.c > > +++ b/drivers/net/wireless/p54/p54usb.c > > @@ -1053,6 +1053,10 @@ static int p54u_probe(struct usb_interface *intf, > > priv->upload_fw = p54u_upload_firmware_net2280; > > } > > err = p54u_load_firmware(dev, intf); > > + if (err) { > > + usb_put_dev(udev); > > + p54_free_common(dev); > > + } > > return err; > > } > The load_firmware puts down the reference > in case of error. Only free is required here. No, the put is required too... But let me explain: p54u_load_firmware calls usb_get_dev(udev) before it requests the firmware load. The Reason is: the firmware callback is usually run in another thread (usually it's pretty quick, but due to timeouts it could take up to 60 seconds - or at least it did when I wrote it). Therefore I found it appropriate to give that request callback its "reference++" as it needs the "udev" too (e.g.: for dev_info, dev_err and releasing the driver if the device couldn't be initialized). Regards, Christian -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sun, Mar 9, 2014 at 4:38 AM, Christian Lamparter <chunkeey@googlemail.com> wrote: > On Sunday, March 09, 2014 04:14:32 AM Krishna Chaitanya wrote: >> On Sat, Mar 8, 2014 at 2:41 AM, Alexey Khoroshilov >> <khoroshilov@ispras.ru> wrote: >> > If p54u_load_firmware() fails, p54u_probe() does not deallocate >> > already allocated resources. The patch adds proper failure handling. >> > >> > Found by Linux Driver Verification project (linuxtesting.org). >> > >> > Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> >> > --- >> > drivers/net/wireless/p54/p54usb.c | 4 ++++ >> > 1 file changed, 4 insertions(+) >> > >> > diff --git a/drivers/net/wireless/p54/p54usb.c b/drivers/net/wireless/p54/p54usb.c >> > index 6e635cfa24c8..5df74503fd4f 100644 >> > --- a/drivers/net/wireless/p54/p54usb.c >> > +++ b/drivers/net/wireless/p54/p54usb.c >> > @@ -1053,6 +1053,10 @@ static int p54u_probe(struct usb_interface *intf, >> > priv->upload_fw = p54u_upload_firmware_net2280; >> > } >> > err = p54u_load_firmware(dev, intf); >> > + if (err) { >> > + usb_put_dev(udev); >> > + p54_free_common(dev); >> > + } >> > return err; >> > } >> The load_firmware puts down the reference >> in case of error. Only free is required here. > No, the put is required too... But let me explain: > > p54u_load_firmware calls usb_get_dev(udev) before it requests the firmware > load. The Reason is: the firmware callback is usually run in another thread > (usually it's pretty quick, but due to timeouts it could take up to 60 seconds > - or at least it did when I wrote it). Therefore I found it appropriate to give > that request callback its "reference++" as it needs the "udev" too (e.g.: for > dev_info, dev_err and releasing the driver if the device couldn't be > initialized). > Thanks Christian and Alexey, you answered my next question as well :-). -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/wireless/p54/p54usb.c b/drivers/net/wireless/p54/p54usb.c index 6e635cfa24c8..5df74503fd4f 100644 --- a/drivers/net/wireless/p54/p54usb.c +++ b/drivers/net/wireless/p54/p54usb.c @@ -1053,6 +1053,10 @@ static int p54u_probe(struct usb_interface *intf, priv->upload_fw = p54u_upload_firmware_net2280; } err = p54u_load_firmware(dev, intf); + if (err) { + usb_put_dev(udev); + p54_free_common(dev); + } return err; }
If p54u_load_firmware() fails, p54u_probe() does not deallocate already allocated resources. The patch adds proper failure handling. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> --- drivers/net/wireless/p54/p54usb.c | 4 ++++ 1 file changed, 4 insertions(+)