[ar71xx] fix handling of invalid arguments passed by some bootloaders (thanks to...

[openwrt.git] / target / linux / ar71xx / files / arch / mips / ar71xx / prom.c

diff --git a/target/linux/ar71xx/files/arch/mips/ar71xx/prom.c b/target/linux/ar71xx/files/arch/mips/ar71xx/prom.c
index 8e93807..5402e0a 100644 (file)
--- a/target/linux/ar71xx/files/arch/mips/ar71xx/prom.c
+++ b/target/linux/ar71xx/files/arch/mips/ar71xx/prom.c
@@ -73,18 +73,31 @@ static struct board_rec boards[] __initdata = {
        }
 };
 
+static inline int is_valid_ram_addr(void *addr)
+{
+       if (((u32) addr > KSEG0) &&
+           ((u32) addr < (KSEG0 + AR71XX_MEM_SIZE_MAX)))
+               return 1;
+
+       if (((u32) addr > KSEG1) &&
+           ((u32) addr < (KSEG1 + AR71XX_MEM_SIZE_MAX)))
+               return 1;
+
+       return 0;
+}
+
 static __init char *ar71xx_prom_getargv(const char *name)
 {
        int len = strlen(name);
        int i;
 
-       if (!ar71xx_prom_argv)
+       if (!is_valid_ram_addr(ar71xx_prom_argv))
                return NULL;
 
        for (i = 0; i < ar71xx_prom_argc; i++) {
                char *argv = ar71xx_prom_argv[i];
 
-               if (!argv)
+               if (!is_valid_ram_addr(argv))
                        continue;
 
                if (strncmp(name, argv, len) == 0 && (argv)[len] == '=')
@@ -99,10 +112,10 @@ static __init char *ar71xx_prom_getenv(const char *envname)
        int len = strlen(envname);
        char **env;
 
-       if (!ar71xx_prom_envp)
+       if (!is_valid_ram_addr(ar71xx_prom_envp))
                return NULL;
 
-       for (env = ar71xx_prom_envp; *env != NULL; env++)
+       for (env = ar71xx_prom_envp; is_valid_ram_addr(*env); env++)
                if (strncmp(envname, *env, len) == 0 && (*env)[len] == '=')
                        return *env + len + 1;