Linux · Linux Kernel · CVE-2024-56640
**Name of the Vulnerable Software and Affected Versions**
Linux kernel versions prior to 6.6.74
**Description**
A use-after-free issue was encountered in the Linux kernel, specifically in the net/smc component. This issue manifested as the LGR/link refcnt reaching 0 early and entering the clear process, making resource access unsafe. The problem is caused by repeated release of LGR/link refcnt, potentially due to smc conn free() being called repeatedly without sock lock protection.
**Recommendations**
Update to Linux kernel version 6.6.74 or later to resolve the issue.
As a temporary workaround, consider adding sock lock protection in the smc listen work() path to prevent repeated release of LGR/link refcnt.