The Linux kernel's NFS server component had a flaw where, upon failure of the inter-server COPY setup in nfsd4_setup_inter_ssc(), the function nfsd4_copy() returned an error code directly instead of executing the cleanup path labeled 'out:'. This caused the nf_dst reference taken by nfs4_preprocess_stateid_op() to not be released, leaking one nfsd_file per failed COPY attempt. The leaked nfsd_file pins associated file, inode, dentry, and vfsmount structures, leading to resource exhaustion. The fix involved modifying the code to set the status and jump to the cleanup label to properly release resources.

Each failed inter-server COPY operation leaks kernel resources related to file handling, including file, inode, dentry, and vfsmount references. Over time, this can lead to resource exhaustion in the kernel, potentially degrading system stability or causing denial of service conditions. There is no indication of direct code execution or privilege escalation from this leak.

A fix has been implemented in the Linux kernel source code to address this resource leak by ensuring proper cleanup on failure paths. Users should apply the official Linux kernel updates that include this patch. Since no vendor advisory or patch link is provided here, check the Linux kernel mailing lists or official repositories for the relevant patch and update accordingly.