kernel: race condition in snd_seq_write() may lead to UAF or OOB-access

ALSA sequencer core initializes the event pool on demand by invoking sndseqpoolinit when the first write happens and the pool is empty. A user can reset the pool size manually via ioctl concurrently, and this may lead to UAF or out-of-bound access...

The vulnerability of the functions snd_seq_write and snd_seq_ioctl_set_client_pool (seq_clientmgr.c) in the Linux kernel sound subsystem allows a attacker to cause a service failure.

The vulnerability of the sndseqwrite and sndseqioctlsetclientpool functions in the Linux kernel’s audio subsystem is related to multiprogramming errors race conditions. Exploiting this vulnerability can allow a remote attacker to cause service failures...