CVE-2026-22994

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

bpf: Fix reference count leak in bpfprogtestrunxdp()

syzbot is reporting

unregister_netdevice: waiting for sit0 to become free. Usage count = 2

problem. A debug printk() patch found that a refcount is obtained at xdpconvertmdtobuff() from bpfprogtestrunxdp().

According to commit ec94670fcb3b ("bpf: Support specifying ingress via xdpmd context in BPFPROGTESTRUN"), the refcount obtained by xdpconvertmdtobuff() will be released by xdpconvertbufftomd().

Therefore, we can consider that the error handling path introduced by commit 1c1949982524 ("bpf: introduce frags support to bpfprogtestrunxdp()") forgot to call xdpconvertbufftomd().