[urgent] [loongson] machtype: Fixup of prom_init_machtype()

[Wu Zhangjin <wuzhangjin@gmail.com>]

From: Wu Zhangjin <wuzhangjin@gmail.com>

The old version cut off everything of arcs_cmdline after machtype=xxxx,
which is totally wrong, we need to copy out the machtype=xxxx and then
operate it.

Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
---
 arch/mips/loongson/common/machtype.c |   14 +++++++++-----
 1 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/arch/mips/loongson/common/machtype.c 
b/arch/mips/loongson/common/machtype.c
index 2a46b4d..0ed52b3 100644
--- a/arch/mips/loongson/common/machtype.c
+++ b/arch/mips/loongson/common/machtype.c
@@ -15,6 +15,9 @@
 #include <loongson.h>
 #include <machine.h>
 
+/* please ensure the length of the machtype string is less than 50 */
+#define MACHTYPE_LEN 50
+
 static const char *system_types[] = {
        [MACH_LOONGSON_UNKNOWN]         "unknown loongson machine",
        [MACH_LEMOTE_FL2E]              "lemote-fuloong-2e-box",
@@ -34,18 +37,19 @@ const char *get_system_type(void)
 
 void __init prom_init_machtype(void)
 {
-       char *str, *p;
+       char *p, str[MACHTYPE_LEN];
        int machtype = MACH_LEMOTE_FL2E;
 
        mips_machtype = LOONGSON_MACHTYPE;
 
-       str = strstr(arcs_cmdline, "machtype=");
-       if (!str)
+       p = strstr(arcs_cmdline, "machtype=");
+       if (!p)
                return;
-       str += strlen("machtype=");
+       p += strlen("machtype=");
+       strncpy(str, p, MACHTYPE_LEN);
        p = strstr(str, " ");
        if (p)
-               *p++ = '\0';
+               *p = '\0';
 
        for (; system_types[machtype]; machtype++)
                if (strstr(system_types[machtype], str)) {
-- 
1.6.2.1