CVE-2024-26899

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: bloque: soluciona el punto muerto entre bd_link_disk_holder y el análisis de partición. 'open_mutex' de gendisk se utiliza para proteger dispositivos de bloqueo de apertura/cierre. Pero en bd_link_disk_holder(), se utiliza para proteger la creación de un enlace simbólico entre el disco de retención y el bdev esclavo, lo que introduce algunos problemas. Cuando se llama a bd_link_disk_holder(), el controlador generalmente está en el proceso de inicialización/modificación y puede suspender el envío de io. En este momento, cualquier retención de io 'open_mutex', como escanear particiones, puede causar interbloqueos. Por ejemplo, en raid: T1 T2 bdev_open_by_dev lock open_mutex [1] ... efi_partition ... md_submit_bio md_ioctl mddev_syspend -> suspender todo io md_add_new_disk bind_rdev_to_array bd_link_disk_holder try lock open_mutex [2] md_handle_request -> esperar mddev_resume T1 escanear partición, agregar un Nuevo dispositivo para atacar. T1 espera a que T2 reanude mddev, pero T2 espera a open_mutex retenido por T1. Se produce un punto muerto. Solucionarlo introduciendo un mutex local 'blk_holder_mutex' para reemplazar 'open_mutex'.

A flaw was found in the Linux kernel, where a deadlock can occur between bd_link_disk_holder and partition scan.

In the Linux kernel, the following vulnerability has been resolved: block: fix deadlock between bd_link_disk_holder and partition scan 'open_mutex' of gendisk is used to protect open/close block devices. But in bd_link_disk_holder(), it is used to protect the creation of symlink between holding disk and slave bdev, which introduces some issues. When bd_link_disk_holder() is called, the driver is usually in the process of initialization/modification and may suspend submitting io. At this time, any io hold 'open_mutex', such as scanning partitions, can cause deadlocks. For example, in raid: T1 T2 bdev_open_by_dev lock open_mutex [1] ... efi_partition ... md_submit_bio md_ioctl mddev_syspend -> suspend all io md_add_new_disk bind_rdev_to_array bd_link_disk_holder try lock open_mutex [2] md_handle_request -> wait mddev_resume T1 scan partition, T2 add a new device to raid. T1 waits for T2 to resume mddev, but T2 waits for open_mutex held by T1. Deadlock occurs. Fix it by introducing a local mutex 'blk_holder_mutex' to replace 'open_mutex'.

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.