CVE-2022-50543: 
Linux Kernel vulnerability analysis and mitigation

CVE-2022-50543 is a vulnerability in the Linux kernel's RDMA/rxe component that involves a double-free issue in the mr->map handling. The issue was discovered in version 6.1.0-rc1 and affects the memory management in the RDMA (Remote Direct Memory Access) subsystem (NVD).

The vulnerability occurs when rxemrcleanup() attempts to free mr->map again after rxemrinituser() fails. This issue was initially exposed after commit b18c7da63fcb ("RDMA/rxe: Fix memory leak in error path code") and was temporarily fixed in commit 8ff5f5d9d8cf ("RDMA/rxe: Prevent double freeing rxemap_set()"), but this fix was later reverted by commit 1e75550648da. The vulnerability has a CVSS v3.1 base score of 7.0 with vector AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H (RedHat).

The vulnerability could lead to system crashes and potential memory corruption due to the double-free condition in the RDMA subsystem. This affects systems using the RDMA/rxe component and could potentially be exploited to cause denial of service or possible privilege escalation (RedHat).

The fix involves ensuring that rxemrcleanup() always handles freeing the mr->map once it is successfully allocated. This was implemented in the Linux kernel to prevent the double-free condition (NVD).