diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 3c6670cf905f..ec176debb778 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -30,6 +30,8 @@
 #include <linux/uio.h>
 #include <linux/uaccess.h>
 #include <linux/security.h>
+#include <linux/minmax.h>
+#include <linux/printk.h>
 
 #define DEVMEM_MINOR	1
 #define DEVPORT_MINOR	4
@@ -428,7 +430,20 @@ static ssize_t write_port(struct file *file, const char __user *buf,
 static ssize_t read_null(struct file *file, char __user *buf,
 			 size_t count, loff_t *ppos)
 {
-	return 0;
+	static const char content[] = "null\n";
+	size_t content_length = sizeof(content);
+
+	if (*ppos >= content_length)
+		return 0;
+
+	size_t copy_len = min(content_length - *ppos, count);
+	if (copy_to_user(buf, content + *ppos, copy_len)) {
+		pr_err("null: User copy failed\n");
+		return -EFAULT;
+	}
+
+	*ppos += copy_len;
+	return copy_len;
 }
 
 static ssize_t write_null(struct file *file, const char __user *buf,
@@ -437,33 +452,23 @@ static ssize_t write_null(struct file *file, const char __user *buf,
 	return count;
 }
 
-static ssize_t read_iter_null(struct kiocb *iocb, struct iov_iter *to)
-{
-	return 0;
-}
-
-static ssize_t write_iter_null(struct kiocb *iocb, struct iov_iter *from)
+static ssize_t write_iter_zero(struct kiocb *iocb, struct iov_iter *from)
 {
 	size_t count = iov_iter_count(from);
 	iov_iter_advance(from, count);
 	return count;
 }
 
-static int pipe_to_null(struct pipe_inode_info *info, struct pipe_buffer *buf,
+static int pipe_to_zero(struct pipe_inode_info *info, struct pipe_buffer *buf,
 			struct splice_desc *sd)
 {
 	return sd->len;
 }
 
-static ssize_t splice_write_null(struct pipe_inode_info *pipe, struct file *out,
+static ssize_t splice_write_zero(struct pipe_inode_info *pipe, struct file *out,
 				 loff_t *ppos, size_t len, unsigned int flags)
 {
-	return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_null);
-}
-
-static int uring_cmd_null(struct io_uring_cmd *ioucmd, unsigned int issue_flags)
-{
-	return 0;
+	return splice_from_pipe(pipe, out, ppos, len, flags, pipe_to_zero);
 }
 
 static ssize_t read_iter_zero(struct kiocb *iocb, struct iov_iter *iter)
@@ -627,8 +632,6 @@ static int open_port(struct inode *inode, struct file *filp)
 #define zero_lseek	null_lseek
 #define full_lseek      null_lseek
 #define write_zero	write_null
-#define write_iter_zero	write_iter_null
-#define splice_write_zero	splice_write_null
 #define open_mem	open_port
 
 static const struct file_operations __maybe_unused mem_fops = {
@@ -644,13 +647,8 @@ static const struct file_operations __maybe_unused mem_fops = {
 };
 
 static const struct file_operations null_fops = {
-	.llseek		= null_lseek,
 	.read		= read_null,
 	.write		= write_null,
-	.read_iter	= read_iter_null,
-	.write_iter	= write_iter_null,
-	.splice_write	= splice_write_null,
-	.uring_cmd	= uring_cmd_null,
 };
 
 static const struct file_operations __maybe_unused port_fops = {