nfsd: Fix error return values for nfsd4_clone_file_range()

commit e3fdc89ca47ef34dfb6fd5101fec084c3dba5486 upstream.

If the parameter 'count' is non-zero, nfsd4_clone_file_range() will
currently clobber all errors returned by vfs_clone_file_range() and
replace them with EINVAL.

Fixes: 42ec3d4c0218 ("vfs: make remap_file_range functions take and...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index eb67098117b4c09eeaa1bf81f08139deba4dd23a..6f424e3a39812f1b257a1af693b628afccb21577 100644 (file)
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -544,9 +544,11 @@ __be32 nfsd4_clone_file_range(struct file *src, u64 src_pos, struct file *dst,
        loff_t cloned;
 
        cloned = vfs_clone_file_range(src, src_pos, dst, dst_pos, count, 0);
+       if (cloned < 0)
+               return nfserrno(cloned);
        if (count && cloned != count)
-               cloned = -EINVAL;
-       return nfserrno(cloned < 0 ? cloned : 0);
+               return nfserrno(-EINVAL);
+       return 0;
 }
 
 ssize_t nfsd_copy_file_range(struct file *src, u64 src_pos, struct file *dst,