CVE-2025-38567

In the Linux kernel, the following vulnerability has been resolved:

nfsd: avoid ref leak in nfsdopenlocal_fh()

If two calls to nfsdopenlocalfh() race and both successfully call nfsdfileacquirelocal(), they will both get an extra reference to the net to accompany the file reference stored in *pnf.

One of them will fail to store (using xchg()) the file reference in *pnf and will drop that reference but WON'T drop the accompanying reference to the net. This leak means that when the nfs server is shut down it will hang in nfsdshutdownnet() waiting for &nn->nfsdnetfree_done.

This patch adds the missing nfsdnetput().