diff --git a/sys/compat/linuxkpi/common/src/linux_seq_file.c b/sys/compat/linuxkpi/common/src/linux_seq_file.c
index 6f4f1a368c4a..ed23bf8d010f 100644
--- a/sys/compat/linuxkpi/common/src/linux_seq_file.c
+++ b/sys/compat/linuxkpi/common/src/linux_seq_file.c
@@ -1,156 +1,162 @@
 /*-
  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
  *
  * Copyright (c) 2016-2018, Matthew Macy <mmacy@freebsd.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
  */
 
 #include <sys/cdefs.h>
 __FBSDID("$FreeBSD$");
 
 #include <sys/types.h>
 #include <sys/systm.h>
 #include <sys/param.h>
 #include <sys/sbuf.h>
 #include <sys/syslog.h>
 #include <sys/vnode.h>
 
 #include <linux/seq_file.h>
 #include <linux/file.h>
 
 #undef file
 MALLOC_DEFINE(M_LSEQ, "seq_file", "seq_file");
 
 ssize_t
 seq_read(struct linux_file *f, char *ubuf, size_t size, off_t *ppos)
 {
 	struct seq_file *m = f->private_data;
 	void *p;
 	int rc;
 	off_t pos = 0;
 
 	p = m->op->start(m, &pos);
 	rc = m->op->show(m, p);
 	if (rc)
 		return (rc);
 	return (size);
 }
 
 int
 seq_write(struct seq_file *seq, const void *data, size_t len)
 {
 
 	return (sbuf_bcpy(seq->buf, data, len));
 }
 
 /*
  * This only needs to be a valid address for lkpi
  * drivers it should never actually be called
  */
 off_t
 seq_lseek(struct linux_file *file, off_t offset, int whence)
 {
 
 	panic("%s not supported\n", __FUNCTION__);
 	return (0);
 }
 
 static void *
 single_start(struct seq_file *p, off_t *pos)
 {
 
 	return ((void *)(uintptr_t)(*pos == 0));
 }
 
 static void *
 single_next(struct seq_file *p, void *v, off_t *pos)
 {
 
 	++*pos;
 	return (NULL);
 }
 
 static void
 single_stop(struct seq_file *p, void *v)
 {
 }
 
 int
 seq_open(struct linux_file *f, const struct seq_operations *op)
 {
 	struct seq_file *p;
 
 	if (f->private_data != NULL)
 		log(LOG_WARNING, "%s private_data not NULL", __func__);
 
 	if ((p = malloc(sizeof(*p), M_LSEQ, M_NOWAIT|M_ZERO)) == NULL)
 		return (-ENOMEM);
 
 	f->private_data = p;
 	p->op = op;
 	p->file = f;
 	return (0);
 }
 
 int
 single_open(struct linux_file *f, int (*show)(struct seq_file *, void *), void *d)
 {
 	struct seq_operations *op;
 	int rc = -ENOMEM;
 
 	op = malloc(sizeof(*op), M_LSEQ, M_NOWAIT);
 	if (op) {
 		op->start = single_start;
 		op->next = single_next;
 		op->stop = single_stop;
 		op->show = show;
 		rc = seq_open(f, op);
 		if (rc)
 			free(op, M_LSEQ);
 		else
 			((struct seq_file *)f->private_data)->private = d;
 	}
 	return (rc);
 }
 
 int
 seq_release(struct inode *inode __unused, struct linux_file *file)
 {
 	struct seq_file *m;
 
 	m = file->private_data;
 	free(m, M_LSEQ);
 	return (0);
 }
 
 int
 single_release(struct vnode *v, struct linux_file *f)
 {
-	const struct seq_operations *op = ((struct seq_file *)f->private_data)->op;
+	const struct seq_operations *op;
+	struct seq_file *m;
 	int rc;
 
+	/* be NULL safe */
+	if ((m = f->private_data) == NULL)
+		return (0);
+
+	op = m->op;
 	rc = seq_release(v, f);
 	free(__DECONST(void *, op), M_LSEQ);
 	return (rc);
 }