CVE-2024-50130

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: netfilter: bpf: debe contener referencia en el espacio de nombres net ERROR: KASAN: slab-use-after-free en __nf_unregister_net_hook+0x640/0x6b0 Lectura de tamaño 8 en la dirección ffff8880106fe400 por la tarea repro/72= bpf_nf_link_release+0xda/0x1e0 bpf_link_free+0x139/0x2d0 bpf_link_release+0x68/0x80 __fput+0x414/0xb60 Eric dice: Parece que bpf pudo diferir __nf_unregister_net_hook() después del tiempo de exit()/close(). Quizás falta una referencia a netns, porque netns ya se ha desmantelado/liberado. bpf_nf_link_attach() hace: link->net = net; Pero no veo que se tome ninguna referencia en net. Agregue dicha referencia y libérela después de anular el registro. Tenga en cuenta que no pude hacer que funcionara el reproductor syzbot, por lo que no sé si esto resuelve este problema.

In the Linux kernel, the following vulnerability has been resolved: netfilter: bpf: must hold reference on net namespace BUG: KASAN: slab-use-after-free in __nf_unregister_net_hook+0x640/0x6b0 Read of size 8 at addr ffff8880106fe400 by task repro/72= bpf_nf_link_release+0xda/0x1e0 bpf_link_free+0x139/0x2d0 bpf_link_release+0x68/0x80 __fput+0x414/0xb60 Eric says: It seems that bpf was able to defer the __nf_unregister_net_hook() after exit()/close() time. Perhaps a netns reference is missing, because the netns has been dismantled/freed already. bpf_nf_link_attach() does : link->net = net; But I do not see a reference being taken on net. Add such a reference and release it after hook unreg. Note that I was unable to get syzbot reproducer to work, so I do not know if this resolves this splat.

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system.