CVE-2025-39984CVE-2025-39984

In the Linux kernel, the following vulnerability has been resolved: net: tun: Update napi->skb after XDP process The syzbot report a UAF issue: BUG: KASAN: slab-use-after-free in skb_reset_mac_header include/linux/skbuff.h:3150 [inline] BUG: KASAN: slab-use-after-free in napi_frags_skb net/core/gro.c:723 [inline] BUG: KASAN: slab-use-after-free in napi_gro_frags+0x6e/0x1030 net/core/gro.c:758 Read of size 8 at addr ffff88802ef22c18 by task syz.0.17/6079 CPU: 0 UID: 0 PID: 6079 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Call Trace: <TASK> dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 skb_reset_mac_header include/linux/skbuff.h:3150 [inline] napi_frags_skb net/core/gro.c:723 [inline] napi_gro_frags+0x6e/0x1030 net/core/gro.c:758 tun_get_user+0x28cb/0x3e20 drivers/net/tun.c:1920 tun_c