From f9826838259e2a5ed20237b35f55eb64cd223b47 Mon Sep 17 00:00:00 2001
From: weishu <twsxtd@gmail.com>
Date: Fri, 26 Apr 2024 13:25:10 +0800
Subject: [PATCH] kernel: refactor PR_REAL_REGS

---
 kernel/arch.h      |  6 ++++++
 kernel/core_hook.c |  6 +-----
 kernel/ksud.c      | 12 ++----------
 kernel/sucompat.c  | 18 +++---------------
 4 files changed, 12 insertions(+), 30 deletions(-)

diff --git a/kernel/arch.h b/kernel/arch.h
index d6be6754..f671b51b 100644
--- a/kernel/arch.h
+++ b/kernel/arch.h
@@ -83,4 +83,10 @@
 #define PT_REGS_SP(x) (__PT_REGS_CAST(x)->__PT_SP_REG)
 #define PT_REGS_IP(x) (__PT_REGS_CAST(x)->__PT_IP_REG)
 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 16, 0)
+#define PT_REAL_REGS(regs) ((struct pt_regs *)PT_REGS_PARM1(regs))
+#else
+#define PT_REAL_REGS(regs) ((regs))
+#endif
+
 #endif
diff --git a/kernel/core_hook.c b/kernel/core_hook.c
index fef98df1..617c1bc8 100644
--- a/kernel/core_hook.c
+++ b/kernel/core_hook.c
@@ -542,11 +542,7 @@ int ksu_handle_setuid(struct cred *new, const struct cred *old)
 
 static int handler_pre(struct kprobe *p, struct pt_regs *regs)
 {
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 16, 0)
-	struct pt_regs *real_regs = (struct pt_regs *)PT_REGS_PARM1(regs);
-#else
-	struct pt_regs *real_regs = regs;
-#endif
+	struct pt_regs *real_regs = PT_REAL_REGS(regs);
 	int option = (int)PT_REGS_PARM1(real_regs);
 	unsigned long arg2 = (unsigned long)PT_REGS_PARM2(real_regs);
 	unsigned long arg3 = (unsigned long)PT_REGS_PARM3(real_regs);
diff --git a/kernel/ksud.c b/kernel/ksud.c
index 20d7aa44..59171afa 100644
--- a/kernel/ksud.c
+++ b/kernel/ksud.c
@@ -474,11 +474,7 @@ static int execve_handler_pre(struct kprobe *p, struct pt_regs *regs)
 
 static int sys_execve_handler_pre(struct kprobe *p, struct pt_regs *regs)
 {
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 16, 0)
-	struct pt_regs *real_regs = (struct pt_regs *)PT_REGS_PARM1(regs);
-#else
-	struct pt_regs *real_regs = regs;
-#endif
+	struct pt_regs *real_regs = PT_REAL_REGS(regs);
 	const char __user **filename_user = (const char **)&PT_REGS_PARM1(real_regs);
 	const char __user *const __user *__argv =
 		(const char __user *const __user *)PT_REGS_PARM2(real_regs);
@@ -511,11 +507,7 @@ __maybe_unused static int vfs_read_handler_pre(struct kprobe *p, struct pt_regs
 
 static int sys_read_handler_pre(struct kprobe *p, struct pt_regs *regs)
 {
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 16, 0)
-	struct pt_regs *real_regs = (struct pt_regs *)PT_REGS_PARM1(regs);
-#else
-	struct pt_regs *real_regs = regs;
-#endif
+	struct pt_regs *real_regs = PT_REAL_REGS(regs);
 	unsigned int fd = PT_REGS_PARM1(real_regs);
 	char __user **buf_ptr = (char __user **)&PT_REGS_PARM2(real_regs);
 	size_t count_ptr = (size_t *) &PT_REGS_PARM3(real_regs);
diff --git a/kernel/sucompat.c b/kernel/sucompat.c
index f4809d67..44f30982 100644
--- a/kernel/sucompat.c
+++ b/kernel/sucompat.c
@@ -178,11 +178,7 @@ __maybe_unused static int faccessat_handler_pre(struct kprobe *p, struct pt_regs
 
 static int sys_faccessat_handler_pre(struct kprobe *p, struct pt_regs *regs)
 {
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 16, 0)
-	struct pt_regs *real_regs = (struct pt_regs *)PT_REGS_PARM1(regs);
-#else
-	struct pt_regs *real_regs = regs;
-#endif
+	struct pt_regs *real_regs = PT_REAL_REGS(regs);
 	int *dfd = (int *)&PT_REGS_PARM1(real_regs);
 	const char __user **filename_user = (const char **)&PT_REGS_PARM2(real_regs);
 	int *mode = (int *)&PT_REGS_PARM3(real_regs);
@@ -207,11 +203,7 @@ __maybe_unused static int newfstatat_handler_pre(struct kprobe *p, struct pt_reg
 
 static int sys_newfstatat_handler_pre(struct kprobe *p, struct pt_regs *regs)
 {
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 16, 0)
-	struct pt_regs *real_regs = (struct pt_regs *)PT_REGS_PARM1(regs);
-#else
-	struct pt_regs *real_regs = regs;
-#endif
+	struct pt_regs *real_regs = PT_REAL_REGS(regs);
 	int *dfd = (int *)&PT_REGS_PARM1(real_regs);
 	const char __user **filename_user = (const char **)&PT_REGS_PARM2(real_regs);
 	int *flags = (int *)&PT_REGS_SYSCALL_PARM4(real_regs);
@@ -231,11 +223,7 @@ static int execve_handler_pre(struct kprobe *p, struct pt_regs *regs)
 
 static int sys_execve_handler_pre(struct kprobe *p, struct pt_regs *regs)
 {
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 16, 0)
-	struct pt_regs *real_regs = (struct pt_regs *)PT_REGS_PARM1(regs);
-#else
-	struct pt_regs *real_regs = regs;
-#endif
+	struct pt_regs *real_regs = PT_REAL_REGS(regs);
 	const char __user **filename_user = (const char **)&PT_REGS_PARM1(real_regs);
 
 	return ksu_handle_execve_sucompat(AT_FDCWD, filename_user, NULL, NULL, NULL);