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

misc: fastrpc: Fix use-after-free and race in fastrpc_map_find

Currently, there is a race window between the point when the mutex is unlocked in fastrpc_map_lookup and the reference count increasing (fastrpc_map_get) in fastrpc_map_find, which can also lead to use-after-free.

So lets merge fastrpc_map_find into fastrpc_map_lookup which allows us to both protect the maps list by also taking the &fl->lock spinlock and the reference count, since the spinlock will be released only after. Add take_ref argument to make this suitable for all callers.

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

misc: fastrpc: Fix use-after-free and race in fastrpc_map_find

Currently, there is a race window between the point when the mutex is unlocked in fastrpc_map_lookup and the reference count increasing (fastrpc_map_get) in fastrpc_map_find, which can also lead to use-after-free.

So lets merge fastrpc_map_find into fastrpc_map_lookup which allows us to both protect the maps list by also taking the &fl->lock spinlock and the reference count, since the spinlock will be released only after. Add take_ref argument to make this suitable for all callers.

Affected: Ubuntu:16.04:LTS: linux-hwe-edge, Ubuntu:18.04:LTS: linux-aws-5.0, Ubuntu:18.04:LTS: linux-aws-5.3, Ubuntu:18.04:LTS: linux-azure, Ubuntu:18.04:LTS: linux-azure-5.3, Ubuntu:18.04:LTS: linux-azure-edge, Ubuntu:18.04:LTS: linux-gcp, Ubuntu:18.04:LTS: linux-gcp-5.3, Ubuntu:18.04:LTS: linux-gke-4.15, Ubuntu:18.04:LTS: linux-gke-5.4 and 66 more

In the Linux kernel, the following vulnerability has been resolved: misc: fastrpc: Fix use-after-free and race in fastrpc_map_find Currently, there is a race window between the point when the mutex is unlocked in fastrpc_map_lookup and the reference count increasing (fastrpc_map_get) in fastrpc_map_find, which can also lead to use-after-free. So lets merge fastrpc_map_find into fastrpc_map_lookup which allows us to both protect the maps list by also taking the &fl->lock spinlock and the reference count, since the spinlock will be released only after. Add take_ref argument to make this suitable for all callers.

Ein lokaler Angreifer kann mehrere Schwachstellen im Linux-Kernel ausnutzen, um einen Denial-of-Service-Zustand zu erzeugen oder einen unspezifischen Angriff durchzuführen.