On Fri, Jul 01, 2016 at 03:33:30PM +0800, Peter Chen wrote: > skb is checked for null pointer at above code, so skb might be null. > eem_wrap uses it without checking null pointer, fix it by adding null > pointer check. > > Signed-off-by: Peter Chen <peter.chen@xxxxxxx> > --- > drivers/usb/gadget/function/u_ether.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/usb/gadget/function/u_ether.c b/drivers/usb/gadget/function/u_ether.c > index 5f562c1..2bc8823 100644 > --- a/drivers/usb/gadget/function/u_ether.c > +++ b/drivers/usb/gadget/function/u_ether.c > @@ -549,7 +549,7 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb, > unsigned long flags; > > spin_lock_irqsave(&dev->lock, flags); > - if (dev->port_usb) > + if (dev->port_usb && skb) > skb = dev->wrap(dev->port_usb, skb); > spin_unlock_irqrestore(&dev->lock, flags); > if (!skb) { > -- Felipe, please do not queue this patch, it will break the ncm function which the socket buffer may be NULL. If you are ok with below changes, I will submit patch: diff --git a/drivers/usb/gadget/function/f_eem.c b/drivers/usb/gadget/function/f_eem.c index d58bfc3..5e0db68 100644 --- a/drivers/usb/gadget/function/f_eem.c +++ b/drivers/usb/gadget/function/f_eem.c @@ -341,11 +341,15 @@ static struct sk_buff *eem_wrap(struct gether *port, struct sk_buff *skb) { struct sk_buff *skb2 = NULL; struct usb_ep *in = port->in_ep; - int padlen = 0; + int headroom, tailroom, padlen = 0; u16 len = skb->len; - int headroom = skb_headroom(skb); - int tailroom = skb_tailroom(skb); + if (!skb) + return NULL; + + len = skb->len; + headroom = skb_headroom(skb); + tailroom = skb_tailroom(skb); /* When (len + EEM_HLEN + ETH_FCS_LEN) % in->maxpacket) is 0, * stick two bytes of zero-length EEM packet on the end. diff --git a/drivers/usb/gadget/function/f_rndis.c b/drivers/usb/gadget/function/f_rndis.c index c800582..16562e4 100644 --- a/drivers/usb/gadget/function/f_rndis.c +++ b/drivers/usb/gadget/function/f_rndis.c @@ -374,6 +374,9 @@ static struct sk_buff *rndis_add_header(struct gether *port, { struct sk_buff *skb2; + if (!skb) + return NULL; + skb2 = skb_realloc_headroom(skb, sizeof(struct rndis_packet_msg_type)); rndis_add_hdr(skb2); -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html