In the Linux kernel, the following vulnerability has been resolved: smb: client: fix rlist race and missing initialization TCP_Server_Info

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

smb: client: fix rlist race and missing initialization

TCP_Server_Info.rlist is allocated via kzalloc which zeros both ->next
and ->prev to NULL instead of pointing to itself, making list_empty()
always return false and list_add() dereference a NULL ->prev pointer.

Also, cifs_signal_cifsd_for_reconnect() can be called concurrently
from multiple cifsd threads, allowing the same server's rlist node to
be added twice into the local list, corrupting it.