diff mbox series

[v2] net/usb: kalmia: Fix uninit-value in kalmia_send_init_packet

Message ID f0b62f38c042d2dcb8b8e83c827d76db2ac5d7ad.camel@gmail.com
State New
Headers
Series [v2] net/usb: kalmia: Fix uninit-value in kalmia_send_init_packet |

Commit Message

Miko Larsson Jan. 31, 2023, 2:20 p.m. UTC 
  syzbot reports that act_len in kalmia_send_init_packet() is
uninitialized. Fix this by initializing it to 0.

Fixes: d40261236e8e ("net/usb: Add Samsung Kalmia driver for Samsung GT-B3730")
Reported-and-tested-by: syzbot+cd80c5ef5121bfe85b55@syzkaller.appspotmail.com
Signed-off-by: Miko Larsson <mikoxyzzz@gmail.com>
---
v1 -> v2
* Minor alteration of commit message.
* Added 'reported-and-tested-by' which is attributed to syzbot.

 drivers/net/usb/kalmia.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Greg KH Jan. 31, 2023, 2:56 p.m. UTC | #1 
On Tue, Jan 31, 2023 at 03:20:33PM +0100, Miko Larsson wrote:
> syzbot reports that act_len in kalmia_send_init_packet() is
> uninitialized. Fix this by initializing it to 0.
> 
> Fixes: d40261236e8e ("net/usb: Add Samsung Kalmia driver for Samsung GT-B3730")
> Reported-and-tested-by: syzbot+cd80c5ef5121bfe85b55@syzkaller.appspotmail.com
> Signed-off-by: Miko Larsson <mikoxyzzz@gmail.com>

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Jiri Pirko Feb. 1, 2023, 12:19 p.m. UTC | #2 
Tue, Jan 31, 2023 at 03:20:33PM CET, mikoxyzzz@gmail.com wrote:
>syzbot reports that act_len in kalmia_send_init_packet() is
>uninitialized. Fix this by initializing it to 0.
>
>Fixes: d40261236e8e ("net/usb: Add Samsung Kalmia driver for Samsung GT-B3730")
>Reported-and-tested-by: syzbot+cd80c5ef5121bfe85b55@syzkaller.appspotmail.com
>Signed-off-by: Miko Larsson <mikoxyzzz@gmail.com>
>---
>v1 -> v2
>* Minor alteration of commit message.
>* Added 'reported-and-tested-by' which is attributed to syzbot.
>
> drivers/net/usb/kalmia.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
>diff --git a/drivers/net/usb/kalmia.c b/drivers/net/usb/kalmia.c
>index 9f2b70ef39aa..b158fb7bf66a 100644
>--- a/drivers/net/usb/kalmia.c
>+++ b/drivers/net/usb/kalmia.c
>@@ -56,7 +56,7 @@ static int
> kalmia_send_init_packet(struct usbnet *dev, u8 *init_msg, u8 init_msg_len,
> 	u8 *buffer, u8 expected_len)
> {
>-	int act_len;
>+	int act_len = 0;
> 	int status;
> 
> 	netdev_dbg(dev->net, "Sending init packet");

Hmm, this is not the right fix.

If the second call of usb_bulk_msg() in this function returns != 0, the
act_len printed out contains the value from previous usb_bulk_msg() call,
which does not make sense.

Printing act_len on error path is pointless, so rather remove it from
the error message entirely for both usb_bulk_msg() calls.
Miko Larsson Feb. 9, 2023, 2:47 p.m. UTC | #3 
On Wed, 2023-02-01 at 13:19 +0100, Jiri Pirko wrote:
> Tue, Jan 31, 2023 at 03:20:33PM CET, mikoxyzzz@gmail.com wrote:
> > syzbot reports that act_len in kalmia_send_init_packet() is
> > uninitialized. Fix this by initializing it to 0.
> > 
> > Fixes: d40261236e8e ("net/usb: Add Samsung Kalmia driver for
> > Samsung GT-B3730")
> > Reported-and-tested-by:
> > syzbot+cd80c5ef5121bfe85b55@syzkaller.appspotmail.com
> > Signed-off-by: Miko Larsson <mikoxyzzz@gmail.com>
> > ---
> > v1 -> v2
> > * Minor alteration of commit message.
> > * Added 'reported-and-tested-by' which is attributed to syzbot.
> > 
> > drivers/net/usb/kalmia.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/net/usb/kalmia.c b/drivers/net/usb/kalmia.c
> > index 9f2b70ef39aa..b158fb7bf66a 100644
> > --- a/drivers/net/usb/kalmia.c
> > +++ b/drivers/net/usb/kalmia.c
> > @@ -56,7 +56,7 @@ static int
> > kalmia_send_init_packet(struct usbnet *dev, u8 *init_msg, u8
> > init_msg_len,
> >         u8 *buffer, u8 expected_len)
> > {
> > -       int act_len;
> > +       int act_len = 0;
> >         int status;
> > 
> >         netdev_dbg(dev->net, "Sending init packet");
> 
> Hmm, this is not the right fix.
> 
> If the second call of usb_bulk_msg() in this function returns != 0,
> the
> act_len printed out contains the value from previous usb_bulk_msg()
> call,
> which does not make sense.
> 
> Printing act_len on error path is pointless, so rather remove it from
> the error message entirely for both usb_bulk_msg() calls.

Something like this, then?

diff --git a/drivers/net/usb/kalmia.c b/drivers/net/usb/kalmia.c
index 9f2b70ef39aa..613fc6910f14 100644
--- a/drivers/net/usb/kalmia.c
+++ b/drivers/net/usb/kalmia.c
@@ -65,8 +65,8 @@ kalmia_send_init_packet(struct usbnet *dev, u8 *init_msg, u8 init_msg_len,
 		init_msg, init_msg_len, &act_len, KALMIA_USB_TIMEOUT);
 	if (status != 0) {
 		netdev_err(dev->net,
-			"Error sending init packet. Status %i, length %i\n",
-			status, act_len);
+			"Error sending init packet. Status %i\n",
+			status);
 		return status;
 	}
 	else if (act_len != init_msg_len) {
@@ -83,8 +83,8 @@ kalmia_send_init_packet(struct usbnet *dev, u8 *init_msg, u8 init_msg_len,
 
 	if (status != 0)
 		netdev_err(dev->net,
-			"Error receiving init result. Status %i, length %i\n",
-			status, act_len);
+			"Error receiving init result. Status %i\n",
+			status);
 	else if (act_len != expected_len)
 		netdev_err(dev->net, "Unexpected init result length: %i\n",
 			act_len);
Jiri Pirko Feb. 9, 2023, 3:12 p.m. UTC | #4 
Thu, Feb 09, 2023 at 03:47:12PM CET, mikoxyzzz@gmail.com wrote:
>On Wed, 2023-02-01 at 13:19 +0100, Jiri Pirko wrote:
>> Tue, Jan 31, 2023 at 03:20:33PM CET, mikoxyzzz@gmail.com wrote:
>> > syzbot reports that act_len in kalmia_send_init_packet() is
>> > uninitialized. Fix this by initializing it to 0.
>> > 
>> > Fixes: d40261236e8e ("net/usb: Add Samsung Kalmia driver for
>> > Samsung GT-B3730")
>> > Reported-and-tested-by:
>> > syzbot+cd80c5ef5121bfe85b55@syzkaller.appspotmail.com
>> > Signed-off-by: Miko Larsson <mikoxyzzz@gmail.com>
>> > ---
>> > v1 -> v2
>> > * Minor alteration of commit message.
>> > * Added 'reported-and-tested-by' which is attributed to syzbot.
>> > 
>> > drivers/net/usb/kalmia.c | 2 +-
>> > 1 file changed, 1 insertion(+), 1 deletion(-)
>> > 
>> > diff --git a/drivers/net/usb/kalmia.c b/drivers/net/usb/kalmia.c
>> > index 9f2b70ef39aa..b158fb7bf66a 100644
>> > --- a/drivers/net/usb/kalmia.c
>> > +++ b/drivers/net/usb/kalmia.c
>> > @@ -56,7 +56,7 @@ static int
>> > kalmia_send_init_packet(struct usbnet *dev, u8 *init_msg, u8
>> > init_msg_len,
>> >         u8 *buffer, u8 expected_len)
>> > {
>> > -       int act_len;
>> > +       int act_len = 0;
>> >         int status;
>> > 
>> >         netdev_dbg(dev->net, "Sending init packet");
>> 
>> Hmm, this is not the right fix.
>> 
>> If the second call of usb_bulk_msg() in this function returns != 0,
>> the
>> act_len printed out contains the value from previous usb_bulk_msg()
>> call,
>> which does not make sense.
>> 
>> Printing act_len on error path is pointless, so rather remove it from
>> the error message entirely for both usb_bulk_msg() calls.
>
>Something like this, then?

Yes.

>
>diff --git a/drivers/net/usb/kalmia.c b/drivers/net/usb/kalmia.c
>index 9f2b70ef39aa..613fc6910f14 100644
>--- a/drivers/net/usb/kalmia.c
>+++ b/drivers/net/usb/kalmia.c
>@@ -65,8 +65,8 @@ kalmia_send_init_packet(struct usbnet *dev, u8 *init_msg, u8 init_msg_len,
> 		init_msg, init_msg_len, &act_len, KALMIA_USB_TIMEOUT);
> 	if (status != 0) {
> 		netdev_err(dev->net,
>-			"Error sending init packet. Status %i, length %i\n",
>-			status, act_len);
>+			"Error sending init packet. Status %i\n",
>+			status);
> 		return status;
> 	}
> 	else if (act_len != init_msg_len) {
>@@ -83,8 +83,8 @@ kalmia_send_init_packet(struct usbnet *dev, u8 *init_msg, u8 init_msg_len,
> 
> 	if (status != 0)
> 		netdev_err(dev->net,
>-			"Error receiving init result. Status %i, length %i\n",
>-			status, act_len);
>+			"Error receiving init result. Status %i\n",
>+			status);
> 	else if (act_len != expected_len)
> 		netdev_err(dev->net, "Unexpected init result length: %i\n",
> 			act_len);
>
>-- 
>~miko
diff mbox series

Patch

diff --git a/drivers/net/usb/kalmia.c b/drivers/net/usb/kalmia.c
index 9f2b70ef39aa..b158fb7bf66a 100644
--- a/drivers/net/usb/kalmia.c
+++ b/drivers/net/usb/kalmia.c
@@ -56,7 +56,7 @@  static int
 kalmia_send_init_packet(struct usbnet *dev, u8 *init_msg, u8 init_msg_len,
 	u8 *buffer, u8 expected_len)
 {
-	int act_len;
+	int act_len = 0;
 	int status;
 
 	netdev_dbg(dev->net, "Sending init packet");