From 9425bb84d48a84d8bc59dc33601c1d5f778a4032 Mon Sep 17 00:00:00 2001
From: Sebastiano Barezzi <barezzisebastiano@gmail.com>
Date: Tue, 28 Jun 2022 23:10:29 +0200
Subject: [PATCH] init: Add CONFIG_INITRAMFS_IGNORE_SKIP_FLAG

* Ignoring an ignore flag, yikes
* Also replace skip_initramf with want_initramf (omitting last letter for Magisk since it binary patches that out of kernel, I'm not even sure why we're supporting that mess)

Co-authored-by: Erfan Abdi <erfangplus@gmail.com>
Change-Id: Ifdf726f128bc66bf860bbb71024f94f56879710f
---
 fs/proc/cmdline.c | 31 +++++++++++++++++++++++++++++++
 init/initramfs.c  |  2 +-
 usr/Kconfig       | 11 +++++++++++
 3 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/fs/proc/cmdline.c b/fs/proc/cmdline.c
index cbd82dff7e81..57d2d15e88bc 100644
--- a/fs/proc/cmdline.c
+++ b/fs/proc/cmdline.c
@@ -2,10 +2,37 @@
 #include <linux/init.h>
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
+#ifdef CONFIG_INITRAMFS_IGNORE_SKIP_FLAG
+#include <asm/setup.h>
+#endif
+
+#ifdef CONFIG_INITRAMFS_IGNORE_SKIP_FLAG
+#define INITRAMFS_STR_FIND "skip_initramf"
+#define INITRAMFS_STR_REPLACE "want_initramf"
+#define INITRAMFS_STR_LEN (sizeof(INITRAMFS_STR_FIND) - 1)
+
+static char proc_command_line[COMMAND_LINE_SIZE];
+
+static void proc_command_line_init(void) {
+	char *offset_addr;
+
+	strcpy(proc_command_line, saved_command_line);
+
+	offset_addr = strstr(proc_command_line, INITRAMFS_STR_FIND);
+	if (!offset_addr)
+		return;
+
+	memcpy(offset_addr, INITRAMFS_STR_REPLACE, INITRAMFS_STR_LEN);
+}
+#endif
 
 static int cmdline_proc_show(struct seq_file *m, void *v)
 {
+#ifdef CONFIG_INITRAMFS_IGNORE_SKIP_FLAG
+	seq_printf(m, "%s\n", proc_command_line);
+#else
 	seq_printf(m, "%s\n", saved_command_line);
+#endif
 	return 0;
 }
 
@@ -23,6 +50,10 @@ static const struct file_operations cmdline_proc_fops = {
 
 static int __init proc_cmdline_init(void)
 {
+#ifdef CONFIG_INITRAMFS_IGNORE_SKIP_FLAG
+	proc_command_line_init();
+#endif
+
 	proc_create("cmdline", 0, NULL, &cmdline_proc_fops);
 	return 0;
 }
diff --git a/init/initramfs.c b/init/initramfs.c
index bf3af10c500a..b4a81e01fc28 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -613,7 +613,7 @@ static int __init skip_initramfs_param(char *str)
 {
 	if (*str)
 		return 0;
-	do_skip_initramfs = 1;
+	do_skip_initramfs = !IS_ENABLED(CONFIG_INITRAMFS_IGNORE_SKIP_FLAG);
 	return 1;
 }
 __setup("skip_initramfs", skip_initramfs_param);
diff --git a/usr/Kconfig b/usr/Kconfig
index 572dcf7b6a44..e49fd6637f3a 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -21,6 +21,17 @@ config INITRAMFS_SOURCE
 
 	  If you are not sure, leave it blank.
 
+config INITRAMFS_IGNORE_SKIP_FLAG
+	bool "Force initramfs even when skip_initramfs is set"
+	default n
+	help
+	  Ignore skip_initramfs cmdline flag.
+
+	  This should only be used if you have no control over cmdline
+	  passed by your bootloader yet you can't use CMDLINE_FORCE.
+
+	  If unsure say N.
+
 config INITRAMFS_ROOT_UID
 	int "User ID to map to 0 (user root)"
 	depends on INITRAMFS_SOURCE!=""