CVE-2026-81002

Summary

In the Linux kernel, the following vulnerability has been resolved:

xdp: fix zero-copy frame layout

xdp_convert_zc_to_xdp_frame() clones an XSK packet into an order-0 page and advertises PAGE_SIZE as its frame size. It allows the copied frame to occupy the page tail needed by skb_shared_info and records zero headroom even when metadata separates the frame header from packet data. An AF_XDP zero-copy packet redirected through cpumap can therefore make the skb overlap skb_shared_info or place it beyond the allocated page.

Limit the copied layout to SKB_WITH_OVERHEAD(PAGE_SIZE) and include the metadata length in frame headroom. Redirect callers already handle a NULL conversion result.

BUG: KASAN: slab-out-of-bounds in skb_gro_receive Write of size 4 at addr ffff88800cf37004 by task cpumap/1/map:1/146 Call Trace: skb_gro_receive (net/core/gro.c:174) udp_gro_receive (net/ipv4/udp_offload.c:812) inet_gro_receive (net/ipv4/af_inet.c:1539) dev_gro_receive (net/core/gro.c:515) gro_receive_skb (net/core/gro.c:633) cpu_map_kthread_run (kernel/bpf/cpumap.c:395) kthread (kernel/kthread.c:436) ret_from_fork (arch/x86/kernel/process.c:164) ret_from_fork_asm (arch/x86/entry/entry_64.S:255) Kernel panic - not syncing: KASAN: panic_on_warn set …

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxb0d1beeff2a97a0cf1965ea8f1d13b8973f22582 < 444216dacdbebd3e52d5e704facafbb230da09e9affected
LinuxLinuxb0d1beeff2a97a0cf1965ea8f1d13b8973f22582 < 15d1f3c0dbe7a740f779337deb39f23cd8d002c8affected
LinuxLinuxb0d1beeff2a97a0cf1965ea8f1d13b8973f22582 < 68d7cc5512238693670fc19c7a615df631e10edfaffected
LinuxLinuxb0d1beeff2a97a0cf1965ea8f1d13b8973f22582 < 71283aaa6c65b3cec84caf1dc78560985737641faffected
LinuxLinux4.20affected
LinuxLinux0 < 4.20unaffected
LinuxLinux6.12.109 <= 6.12.*unaffected
LinuxLinux6.18.50 <= 6.18.*unaffected
LinuxLinux7.2.4 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References