CVE-2025-38572

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> ipv6: reject malicious packets in ipv6_gso_segment()<br /> <br /> syzbot was able to craft a packet with very long IPv6 extension headers<br /> leading to an overflow of skb-&gt;transport_header.<br /> <br /> This 16bit field has a limited range.<br /> <br /> Add skb_reset_transport_header_careful() helper and use it<br /> from ipv6_gso_segment()<br /> <br /> WARNING: CPU: 0 PID: 5871 at ./include/linux/skbuff.h:3032 skb_reset_transport_header include/linux/skbuff.h:3032 [inline]<br /> WARNING: CPU: 0 PID: 5871 at ./include/linux/skbuff.h:3032 ipv6_gso_segment+0x15e2/0x21e0 net/ipv6/ip6_offload.c:151<br /> Modules linked in:<br /> CPU: 0 UID: 0 PID: 5871 Comm: syz-executor211 Not tainted 6.16.0-rc6-syzkaller-g7abc678e3084 #0 PREEMPT(full)<br /> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025<br /> RIP: 0010:skb_reset_transport_header include/linux/skbuff.h:3032 [inline]<br /> RIP: 0010:ipv6_gso_segment+0x15e2/0x21e0 net/ipv6/ip6_offload.c:151<br /> Call Trace:<br /> <br /> skb_mac_gso_segment+0x31c/0x640 net/core/gso.c:53<br /> nsh_gso_segment+0x54a/0xe10 net/nsh/nsh.c:110<br /> skb_mac_gso_segment+0x31c/0x640 net/core/gso.c:53<br /> __skb_gso_segment+0x342/0x510 net/core/gso.c:124<br /> skb_gso_segment include/net/gso.h:83 [inline]<br /> validate_xmit_skb+0x857/0x11b0 net/core/dev.c:3950<br /> validate_xmit_skb_list+0x84/0x120 net/core/dev.c:4000<br /> sch_direct_xmit+0xd3/0x4b0 net/sched/sch_generic.c:329<br /> __dev_xmit_skb net/core/dev.c:4102 [inline]<br /> __dev_queue_xmit+0x17b6/0x3a70 net/core/dev.c:4679