init/main.c: Alloc initcall_command_line in do_initcall() and free it

Since initcall_command_line is used as a temporary buffer,
it could be freed after usage. Allocate it in do_initcall()
and free it after used.

Link: http://lkml.kernel.org/r/157867227145.17873.17513760552008505454.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

diff --git a/init/main.c b/init/main.c
index 59c418a..0b4e0c8 100644 (file)
--- a/init/main.c
+++ b/init/main.c
@@ -137,8 +137,6 @@ char __initdata boot_command_line[COMMAND_LINE_SIZE];
 char *saved_command_line;
 /* Command line for parameter parsing */
 static char *static_command_line;
-/* Command line for per-initcall parameter parsing */
-static char *initcall_command_line;
 
 static char *execute_command;
 static char *ramdisk_execute_command;
@@ -433,10 +431,6 @@ static void __init setup_command_line(char *command_line)
        if (!saved_command_line)
                panic("%s: Failed to allocate %zu bytes\n", __func__, len);
 
-       initcall_command_line = memblock_alloc(len, SMP_CACHE_BYTES);
-       if (!initcall_command_line)
-               panic("%s: Failed to allocate %zu bytes\n", __func__, len);
-
        static_command_line = memblock_alloc(len, SMP_CACHE_BYTES);
        if (!static_command_line)
                panic("%s: Failed to allocate %zu bytes\n", __func__, len);
@@ -1044,13 +1038,12 @@ static const char *initcall_level_names[] __initdata = {
        "late",
 };
 
-static void __init do_initcall_level(int level)
+static void __init do_initcall_level(int level, char *command_line)
 {
        initcall_entry_t *fn;
 
-       strcpy(initcall_command_line, saved_command_line);
        parse_args(initcall_level_names[level],
-                  initcall_command_line, __start___param,
+                  command_line, __start___param,
                   __stop___param - __start___param,
                   level, level,
                   NULL, &repair_env_string);
@@ -1063,9 +1056,20 @@ static void __init do_initcall_level(int level)
 static void __init do_initcalls(void)
 {
        int level;
+       size_t len = strlen(saved_command_line) + 1;
+       char *command_line;
+
+       command_line = kzalloc(len, GFP_KERNEL);
+       if (!command_line)
+               panic("%s: Failed to allocate %zu bytes\n", __func__, len);
+
+       for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++) {
+               /* Parser modifies command_line, restore it each time */
+               strcpy(command_line, saved_command_line);
+               do_initcall_level(level, command_line);
+       }
 
-       for (level = 0; level < ARRAY_SIZE(initcall_levels) - 1; level++)
-               do_initcall_level(level);
+       kfree(command_line);
 }
 
 /*