CVE-2022-49207: 
Linux Kernel vulnerability analysis and mitigation

CVE-2022-49207 affects the Linux kernel's BPF sockmap functionality. The vulnerability was discovered in the skpsockqueuemsg function where a memory leak occurs during tear down operations. When tcpbpf_sendmsg is running during a tear down operation, data may be enqueued on the ingress msg queue while tear down is trying to free it, leading to memory leaks (Kernel Git, RedHat).

The issue occurs in a race condition between tcpbpfsendmsg and tear down operations. During the tear down process, while dropskmsg() is called, the msg has charged memory from sk by skmemcharge and has sg pages that need to be freed. The vulnerability manifests when memory allocated by skmemcharge and associated pages are not properly freed. The CVSS score for this vulnerability is 5.5 according to RedHat's assessment (RedHat).

The vulnerability can result in memory leaks in the kernel, which over time could lead to system resource exhaustion. This is evidenced by warning messages in the kernel logs related to skstreamkillqueues and inetsock_destruct functions (Kernel Git).

The issue has been fixed by replacing the dropskmsg function with a proper cleanup sequence that uses skmsgfree() followed by kfree(msg). This ensures proper cleanup of allocated resources. The fix was implemented in the Linux kernel through multiple commits (Kernel Git).