process-and-memory/patch.diff

diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index 7093ee21c..b0d25489c 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -386,6 +386,7 @@
 460	common	lsm_set_self_attr	sys_lsm_set_self_attr
 461	common	lsm_list_modules	sys_lsm_list_modules
 462 	common  mseal			sys_mseal
+463	common	get_pid_info		sys_get_pid_info
 
 #
 # Due to a historical design error, certain syscalls are numbered differently
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 575810492..1efb297e1 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -1197,6 +1197,20 @@ asmlinkage long sys_ni_syscall(void);
 
 asmlinkage long sys_ni_posix_timers(void);
 
+/* CONFIG GET PID INFO */
+struct pid_info {
+    int pid;
+    u32 state;
+    const void *stack;
+    u64 age;
+    // int * children;
+    int parent_pid;
+    char root_path[PATH_MAX];
+    char working_directory[PATH_MAX];
+};
+
+asmlinkage long sys_get_pid_info(struct pid_info * p_info_struct, int pid);
+
 /*
  * Kernel code should not call syscalls (i.e., sys_xyzyyz()) directly.
  * Instead, use one of the functions which work equivalently, such as
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index 5bf6148ca..52599890a 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -841,8 +841,11 @@ __SYSCALL(__NR_lsm_list_modules, sys_lsm_list_modules)
 #define __NR_mseal 462
 __SYSCALL(__NR_mseal, sys_mseal)
 
+#define __NR_get_pid_info 463
+__SYSCALL(__NR_get_pid_info, sys_get_pid_info)
+
 #undef __NR_syscalls
-#define __NR_syscalls 463
+#define __NR_syscalls 464
 
 /*
  * 32 bit systems traditionally used different
@@ -866,7 +869,7 @@ __SYSCALL(__NR_mseal, sys_mseal)
 #define __NR_newfstatat __NR3264_fstatat
 #define __NR_fstat __NR3264_fstat
 #endif
-#define __NR_mmap __NR3264_mmap
+#define __NR_mmap __NR3264_mmapmseal
 #define __NR_fadvise64 __NR3264_fadvise64
 #ifdef __NR3264_stat
 #define __NR_stat __NR3264_stat
diff --git a/kernel/Makefile b/kernel/Makefile
index 87866b037..15b5167fc 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -50,6 +50,7 @@ obj-y += rcu/
 obj-y += livepatch/
 obj-y += dma/
 obj-y += entry/
+obj-y += get_pid_info/
 obj-$(CONFIG_MODULES) += module/
 
 obj-$(CONFIG_KCMP) += kcmp.o
diff --git a/kernel/get_pid_info/Makefile b/kernel/get_pid_info/Makefile
new file mode 100644
index 000000000..2139af568
--- /dev/null
+++ b/kernel/get_pid_info/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-y += get_pid_info.o
diff --git a/kernel/get_pid_info/get_pid_info.c b/kernel/get_pid_info/get_pid_info.c
new file mode 100644
index 000000000..21ff5f699
--- /dev/null
+++ b/kernel/get_pid_info/get_pid_info.c
@@ -0,0 +1,76 @@
+//
+// Created by jrathelo on 11/18/24.
+//
+
+#include <linux/syscalls.h>
+#include <linux/kernel.h>
+#include <linux/pid.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/fs_struct.h>
+#include <linux/timekeeping.h>
+#include <linux/dcache.h>
+#include <linux/rcupdate.h>
+#include <linux/path.h>
+
+static long    __sys_get_pid_info(struct pid_info __user * p_info_struct, int pid) {
+    struct task_struct *task;
+    char * path;
+    struct timespec64 current_time;
+
+    struct pid_info *data = (struct pid_info *) kzalloc(sizeof(struct pid_info), GFP_KERNEL);
+    if (data == NULL) {
+        return -ENOMEM;
+    }
+
+    int error = copy_from_user(data, p_info_struct, sizeof(struct pid_info));
+    if (error) {
+        kfree(data);
+        return -EFAULT;
+    }
+
+    rcu_read_lock();
+    task = pid_task(find_vpid(pid), PIDTYPE_PID);
+    if (task) {
+        data->pid = pid;
+        data->state = task->__state;
+        data->stack = task->stack;
+        ktime_get_boottime_ts64(&current_time);
+        data->age = (timespec64_to_ns(&current_time) - task->start_time);
+        if (task->parent) {
+            data->parent_pid = task->parent->pid;
+        } else {
+            data->parent_pid = 0;
+        }
+        if (!task->fs) {
+            memset(data->root_path, 0, PATH_MAX);
+            memset(data->working_directory, 0, PATH_MAX);
+            rcu_read_unlock();
+            return 0;
+        }
+        path = d_path(&task->fs->root, data->root_path, PATH_MAX);
+        if (IS_ERR(path)) {
+            memset(data->root_path, 0, PATH_MAX);
+        } else {
+            memcpy(data->root_path, path, PATH_MAX);
+        }
+        path = d_path(&task->fs->pwd, data->working_directory, PATH_MAX);
+        if (IS_ERR(path)) {
+            memset(data->working_directory, 0, PATH_MAX);
+        } else {
+            memcpy(data->working_directory, path, PATH_MAX);
+        }
+    }
+    rcu_read_unlock();
+    error = copy_to_user(p_info_struct, data, sizeof(struct pid_info));
+    if (error) {
+        kfree(data);
+        return -EFAULT;
+    }
+    kfree(data);
+    return 0;
+}
+
+SYSCALL_DEFINE2(get_pid_info, struct pid_info __user *, p_info_struct, int, pid) {
+    return __sys_get_pid_info(p_info_struct, pid);
+}
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index c00a86931..95daa731d 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -392,3 +392,5 @@ COND_SYSCALL(setuid16);
 COND_SYSCALL(rseq);
 
 COND_SYSCALL(uretprobe);
+
+COND_SYSCALL(get_pid_info);