CVE-2024-26951

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: wireguard: netlink: verifique si hay pares pendientes a través de is_dead en lugar de una lista vacía. Si todos los pares se eliminan a través de wg_peer_remove_all(), en lugar de configurar peer_list como vacío, el par se agrega a una lista temporal. lista con un encabezado en la pila de wg_peer_remove_all(). Si se reanuda un volcado de netlink y el par seleccionado es uno que se eliminó mediante wg_peer_remove_all(), iterará desde ese par y luego intentará volcar los pares liberados. Para solucionar este problema, marque peer->is_dead, que se creó explícitamente para este propósito. También suba la aserción de bloqueo de dispositivo_update_lock, ya que la lectura is_dead depende de eso. Se puede reproducir mediante un pequeño script como: echo "Configuración de configuración..." ip link add dev wg0 tipo wireguard wg setconf wg0 /big-config (mientras sea verdadero; haga echo "Mostrando configuración..." wg showconf wg0 > / dev/null done) & sleep 4 wg setconf wg0 <(printf "[Peer]
PublicKey=$(wg genkey)
") Resultando en: ERROR: KASAN: slab-use-after-free en __lock_acquire+0x182a/0x1b20 Lectura de tamaño 8 en la dirección ffff88811956ec70 mediante la tarea wg/59 CPU: 2 PID: 59 Comm: wg Not tainted 6.8.0-rc2-debug+ #5 Seguimiento de llamadas: dump_stack_lvl+0x47/0x70 print_address_description.constprop.0+0x2c /0x380 print_report+0xab/0x250 kasan_report+0xba/0xf0 __lock_acquire+0x182a/0x1b20 lock_acquire+0x191/0x4b0 down_read+0x80/0x440 get_peer+0x140/0xcb0 wg_get_device_dump+0x471/0x1130

In the Linux kernel, the following vulnerability has been resolved: wireguard: netlink: check for dangling peer via is_dead instead of empty list If all peers are removed via wg_peer_remove_all(), rather than setting peer_list to empty, the peer is added to a temporary list with a head on the stack of wg_peer_remove_all(). If a netlink dump is resumed and the cursored peer is one that has been removed via wg_peer_remove_all(), it will iterate from that peer and then attempt to dump freed peers. Fix this by instead checking peer->is_dead, which was explictly created for this purpose. Also move up the device_update_lock lockdep assertion, since reading is_dead relies on that. It can be reproduced by a small script like: echo "Setting config..." ip link add dev wg0 type wireguard wg setconf wg0 /big-config ( while true; do echo "Showing config..." wg showconf wg0 > /dev/null done ) & sleep 4 wg setconf wg0 <(printf "[Peer]
PublicKey=$(wg genkey)
") Resulting in: BUG: KASAN: slab-use-after-free in __lock_acquire+0x182a/0x1b20 Read of size 8 at addr ffff88811956ec70 by task wg/59 CPU: 2 PID: 59 Comm: wg Not tainted 6.8.0-rc2-debug+ #5 Call Trace: <TASK> dump_stack_lvl+0x47/0x70 print_address_description.constprop.0+0x2c/0x380 print_report+0xab/0x250 kasan_report+0xba/0xf0 __lock_acquire+0x182a/0x1b20 lock_acquire+0x191/0x4b0 down_read+0x80/0x440 get_peer+0x140/0xcb0 wg_get_device_dump+0x471/0x1130

Ziming Zhang discovered that the DRM driver for VMware Virtual GPU did not properly handle certain error conditions, leading to a NULL pointer dereference. A local attacker could possibly trigger this vulnerability to cause a denial of service. Zheng Wang discovered that the Broadcom FullMAC WLAN driver in the Linux kernel contained a race condition during device removal, leading to a use- after-free vulnerability. A physically proximate attacker could possibly use this to cause a denial of service.