CVE-2024-53140CVE-2024-53140

In the Linux kernel, the following vulnerability has been resolved: netlink: terminate outstanding dump on socket close Netlink supports iterative dumping of data. It provides the families the following ops: - start - (optional) kicks off the dumping process - dump - actual dump helper, keeps getting called until it returns 0 - done - (optional) pairs with .start, can be used for cleanup The whole process is asynchronous and the repeated calls to .dump don't actually happen in a tight loop, but rather are triggered in response to recvmsg() on the socket. This gives the user full control over the dump, but also means that the user can close the socket without getting to the end of the dump. To make sure .start is always paired with .done we check if there is an ongoing dump before freeing the socket, and if so call .done. The complication is that sockets can get freed from BH and .done is allowed to sleep. So we use a workqueue to defer the call, when needed. Unfortunately thi