[PATCH] x86/aslr: use get_cmd_line_ptr() to get command line address

From: Alexander Kuleshov
Date: Thu Jan 21 2016 - 03:48:50 EST


The cmdline.c provides the get_cmd_line_ptr() accessor for the command line
address. In the same time, we get command line address in the
mem_avoid_init() in same way. Let's make the get_cmd_line_ptr() non-static
and use it in the mem_avoid_init() to get command line address to prevent
code duplication.

Signed-off-by: Alexander Kuleshov <kuleshovmail@xxxxxxxxx>
---
arch/x86/boot/compressed/aslr.c | 3 +--
arch/x86/boot/compressed/cmdline.c | 2 +-
arch/x86/boot/compressed/misc.h | 1 +
3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/x86/boot/compressed/aslr.c b/arch/x86/boot/compressed/aslr.c
index 6a9b96b..495a617 100644
--- a/arch/x86/boot/compressed/aslr.c
+++ b/arch/x86/boot/compressed/aslr.c
@@ -160,8 +160,7 @@ static void mem_avoid_init(unsigned long input, unsigned long input_size,
mem_avoid[1].size = initrd_size;

/* Avoid kernel command line. */
- cmd_line = (u64)real_mode->ext_cmd_line_ptr << 32;
- cmd_line |= real_mode->hdr.cmd_line_ptr;
+ cmd_line = get_cmd_line_ptr();
/* Calculate size of cmd_line. */
ptr = (char *)(unsigned long)cmd_line;
for (cmd_line_size = 0; ptr[cmd_line_size++]; )
diff --git a/arch/x86/boot/compressed/cmdline.c b/arch/x86/boot/compressed/cmdline.c
index b68e303..6b913e6 100644
--- a/arch/x86/boot/compressed/cmdline.c
+++ b/arch/x86/boot/compressed/cmdline.c
@@ -13,7 +13,7 @@ static inline char rdfs8(addr_t addr)
return *((char *)(fs + addr));
}
#include "../cmdline.c"
-static unsigned long get_cmd_line_ptr(void)
+unsigned long get_cmd_line_ptr(void)
{
unsigned long cmd_line_ptr = real_mode->hdr.cmd_line_ptr;

diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 3783dc3..7956392 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -60,6 +60,7 @@ static inline void debug_puthex(const char *s)

#if CONFIG_EARLY_PRINTK || CONFIG_RANDOMIZE_BASE
/* cmdline.c */
+unsigned long get_cmd_line_ptr(void);
int cmdline_find_option(const char *option, char *buffer, int bufsize);
int cmdline_find_option_bool(const char *option);
#endif
--
2.7.0.25.gfc10eb5