In the Linux kernel, the following vulnerability has been resolved:
net: cdc_eem: fix tx fixup skb leak
when usbnet transmit a skb, eem fixup it in eemtxfixup(), if skbcopyexpand() failed, it return NULL, usbnetstartxmit() will have no chance to free original skb.
fix it by free orginal skb in eemtxfixup() first, then check skb clone status, if failed, return NULL to usbnet.