initial commit

literally_null.patch

@@ -0,0 +1,96 @@
+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 = {

print_on_clone_and_execve.patch

@@ -0,0 +1,35 @@
+diff --git a/fs/exec.c b/fs/exec.c
+index 5ee2545c3e18..39739119d148 100644
+--- a/fs/exec.c
++++ b/fs/exec.c
+@@ -1939,6 +1939,8 @@ static int do_execveat_common(int fd, struct filename *filename,
+ 		goto out_ret;
+ 	}
+ 
++	pr_info("Task (pid: %d, comm: '%s') executed '%s'\n", current->pid, current->comm, bprm->filename);
++
+ 	retval = count(argv, MAX_ARG_STRINGS);
+ 	if (retval == 0)
+ 		pr_warn_once("process '%s' launched '%s' with NULL argv: empty string added\n",
+diff --git a/kernel/fork.c b/kernel/fork.c
+index 3b9cdb42e757..11c52d81e0c3 100644
+--- a/kernel/fork.c
++++ b/kernel/fork.c
+@@ -2867,6 +2867,7 @@ pid_t kernel_clone(struct kernel_clone_args *args)
+ 	struct task_struct *p;
+ 	int trace = 0;
+ 	pid_t nr;
++	char comm[TASK_COMM_LEN];
+ 
+ 	/*
+ 	 * For legacy clone() calls, CLONE_PIDFD uses the parent_tid argument
+@@ -2915,6 +2916,9 @@ pid_t kernel_clone(struct kernel_clone_args *args)
+ 	pid = get_task_pid(p, PIDTYPE_PID);
+ 	nr = pid_vnr(pid);
+ 
++	get_task_comm(comm, p);
++	pr_info("Task (pid: %d, comm: '%s') cloned to new task (pid: %d, comm: '%.*s')\n", current->pid, current->comm, nr, TASK_COMM_LEN, comm);
++
+ 	if (clone_flags & CLONE_PARENT_SETTID)
+ 		put_user(nr, args->parent_tid);
+