جزئیات آسیب‌پذیری

In the Linux kernel, the following vulnerability has been resolved: s390/cpum_sf: Fix and protect memory allocation of SDBs with mutex Reservation of the PMU hardware is done at first event creation and is protected by a pair of mutex_lock() and mutex_unlock(). After reservation of the PMU hardware the memory required for the PMUs the event is to be installed on is allocated by allocate_buffers() and alloc_sampling_buffer(). This done outside of the mutex protection. Without mutex protection two or more concurrent invocations of perf_event_init() may run in parallel. This can lead to allocation of Sample Data Blocks (SDBs) multiple times for the same PMU. Prevent this and protect memory allocation of SDBs by mutex.

• https://git.kernel.org/stable/c/4b3bdfa89635db6a53e02955548bd07bebcae233
• https://git.kernel.org/stable/c/f55bd479d8663a4a4e403b3d308d3d1aa33d92df