pmaports/device/testing/linux-xiaomi-platina/0003-Add-config-option-to-fix-bootloader-cmdline-args.patch

80 lines
2.4 KiB
Diff

From 92e3310d2db157deacb86ef5db8c8c8d38251312 Mon Sep 17 00:00:00 2001
From: Alexey Min <alexey.min@gmail.com>
Date: Wed, 11 Sep 2019 21:51:40 +0300
Subject: [PATCH 3/6] Add config option to fix bootloader cmdline args
Android bootloader passes some arguments in kernel command
line, that make booting custom OSes harder:
* skip_initramfs
* root=PARTUUID=...
* init=/init
Those parameters override default boot partition to hardcoded,
set init binary to /init, disable booting from initramfs.
If enabled, those parameters will be erased from bootloader's
command line, and custom OS can boot the way it likes.
Signed-off-by: Alexey Min <alexey.min@gmail.com>
---
arch/arm64/Kconfig | 17 +++++++++++++++++
drivers/of/fdt.c | 14 ++++++++++++++
2 files changed, 31 insertions(+)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 2829edba6aa5..bd9f05f83c7e 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1125,6 +1125,23 @@ config CMDLINE_FORCE
command-line options your boot loader passes to the kernel.
endchoice
+config CMDLINE_DROP_DANGEROUS_ANDROID_OPTIONS
+ bool "Drop certain dangerous options from cmdline"
+ default n
+ help
+ Android bootloader passes some arguments in kernel command
+ line, that make booting custom OSes harder:
+
+ * skip_initramfs
+ * root=PARTUUID=...
+ * init=/init
+
+ Those parameters override default boot partition to hardcoded,
+ set init binary to /init, disable booting from initramfs.
+
+ If enabled, those parameters will be erased from bootloader's
+ command line, and custom OS can boot the way it likes.
+
config EFI_STUB
bool
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index ca175710c4c8..fd8257589648 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -1012,6 +1012,20 @@ int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
pr_debug("Command line is: %s\n", (char*)data);
+#ifdef CONFIG_CMDLINE_DROP_DANGEROUS_ANDROID_OPTIONS
+ pr_err("Replacing dangerous cmdline options...");
+ cmdline = strstr((const char *)data, "skip_initramfs");
+ if (cmdline)
+ *cmdline = '_';
+ cmdline = strstr((const char *)data, "root=");
+ if (cmdline)
+ *cmdline = '_';
+ cmdline = strstr((const char *)data, "init=");
+ if (cmdline)
+ *cmdline = '_';
+ pr_err("Command line now is: %s\n", (char*)data);
+#endif
+
/* break now */
return 1;
}
--
2.24.1