In the Linux kernel, the following vulnerability has been resolved: bonding: do not assume skb mac_header is set Drivers must not assume in their ndo_start_xmit() that skbs have their mac_header set. skb->data is all what is needed. bonding seems to be one of the last offender as caught by syzbot: WARNING: CPU: 1 PID: 12155 at include/linux/skbuff.h:2907 skb_mac_offset include/linux/skbuff.h:2913 [inline] WARNING: CPU: 1 PID: 12155 at include/linux/skbuff.h:2907 bond_xmit_hash drivers/net/bonding/bond_main.c:4170 [inline] WARNING: CPU: 1 PID: 12155 at include/linux/skbuff.h:2907 bond_xmit_3ad_xor_slave_get drivers/net/bonding/bond_main.c:5149 [inline] WARNING: CPU: 1 PID: 12155 at include/linux/skbuff.h:2907 bond_3ad_xor_xmit drivers/net/bonding/bond_main.c:5186 [inline] WARNING: CPU: