CVE-2023-52638

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: can: j1939: previene el interbloqueo cambiando j1939_socks_lock a rwlock Los siguientes 3 bloqueos competirían entre sí, causando la situación de interbloqueo en el informe de error de Syzbot: - j1939_socks_lock - active_session_list_lock - sk_session_queue_lock A Una solución razonable es cambiar j1939_socks_lock por un rwlock, ya que en las raras situaciones en las que se requiere un bloqueo de escritura para la lista vinculada que j1939_socks_lock está protegiendo, el código no intenta adquirir más bloqueos. Esto rompería la dependencia del bloqueo circular, donde, por ejemplo, el subproceso actual ya bloquea j1939_socks_lock e intenta adquirir sk_session_queue_lock y, al mismo tiempo, otro subproceso intenta adquirir j1939_socks_lock mientras mantiene sk_session_queue_lock. NOTA: Este parche no soluciona el error unregister_netdevice informado por Syzbot; en cambio, resuelve una situación de punto muerto para prepararse para uno o más parches adicionales para corregir el error Syzbot, que parece ser un problema de conteo de referencias dentro del código base j1939. [mkl: eliminar cambio de nueva línea no relacionado]

A vulnerability was found in the Linux kernel's Controller Area Network (CAN) protocol, within the J1939 protocol implementation. This issue occurs due to a potential deadlock caused by a race condition involving three locks: j1939_socks_lock, active_session_list_lock, and sk_session_queue_lock. This issue was identified in a Syzbot bug report.

In the Linux kernel, the following vulnerability has been resolved: can: j1939: prevent deadlock by changing j1939_socks_lock to rwlock The following 3 locks would race against each other, causing the deadlock situation in the Syzbot bug report: - j1939_socks_lock - active_session_list_lock - sk_session_queue_lock A reasonable fix is to change j1939_socks_lock to an rwlock, since in the rare situations where a write lock is required for the linked list that j1939_socks_lock is protecting, the code does not attempt to acquire any more locks. This would break the circular lock dependency, where, for example, the current thread already locks j1939_socks_lock and attempts to acquire sk_session_queue_lock, and at the same time, another thread attempts to acquire j1939_socks_lock while holding sk_session_queue_lock. NOTE: This patch along does not fix the unregister_netdevice bug reported by Syzbot; instead, it solves a deadlock situation to prepare for one or more further patches to actually fix the Syzbot bug, which appears to be a reference counting problem within the j1939 codebase. [mkl: remove unrelated newline change]

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. It was discovered that the ATA over Ethernet driver in the Linux kernel contained a race condition, leading to a use-after-free vulnerability. An attacker could use this to cause a denial of service or possibly execute arbitrary code.