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ec572b9e81
Commit 34b1744c91cc ("nfsd4: define ->op_release for compound ops")
defined a couple ->op_release functions and run them if necessary.
But there's a problem with that is that it reused
nfsd4_secinfo_release() as the op_release of OP_SECINFO_NO_NAME, and
caused a leak on struct nfsd4_secinfo_no_name in
nfsd4_encode_secinfo_no_name(), because there's no .si_exp field in
struct nfsd4_secinfo_no_name.
I found this because I was unable to umount an ext4 partition after
exporting it via NFS & run fsstress on the nfs mount. A simplified
reproducer would be:
# mount a local-fs device at /mnt/test, and export it via NFS with
# fsid=0 export option (this is required)
mount /dev/sda5 /mnt/test
echo "/mnt/test *(rw,no_root_squash,fsid=0)" >> /etc/exports
service nfs restart
# locally mount the nfs export with all default, note that I have
# nfsv4.1 configured as the default nfs version, because of the
# fsid export option, v4 mount would fail and fall back to v3
mount localhost:/mnt/test /mnt/nfs
# try to umount the underlying device, but got EBUSY
umount /mnt/nfs
service nfs stop
umount /mnt/test <=== EBUSY here
Fixed it by defining a separate nfsd4_secinfo_no_name_release()
function as the op_release method of OP_SECINFO_NO_NAME that
releases the correct nfsd4_secinfo_no_name structure.
Fixes: 34b1744c91cc ("nfsd4: define ->op_release for compound ops")
Signed-off-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>