[PATCH] kernel/param.c: don't use .max when .num is NULL inparam_array_set()

[Bert Wesarg]

Hello,

there seems to be a bug, at least for me, in kernel/param.c for arrays
with .num == NULL. If .num == NULL, the function param_array_set() uses
&.max for the call to param_array(), wich alters the .max value to the
number of arguments. The result is, you can't set more array arguments as
the last time you set the parameter.

example:

# a module 'example' with
# static int array[10] = { 0, };
# module_param_array(array, int, NULL, 0644);

$ insmod example.ko array=1,2,3
$ cat /sys/module/example/parameters/array
1,2,3
$ echo "4,3,2,1" > /sys/module/example/parameters/array
$ dmesg | tail -n 1
kernel: array: can take only 3 arguments

Patch is against 2.6.12-rc1.

Signed-off-by: Bert Wesarg <wesarg@xxxxxxxxxxxxxxxxxxxxxxx>

--- linux-2.6.12-rc1.orig/kernel/params.c	2005-03-27 14:44:00.000000000 +0200
+++ linux-2.6.12-rc1/kernel/params.c	2005-03-27 14:45:55.000000000 +0200
@@ -314,9 +314,10 @@ int param_array(const char *name,
 int param_array_set(const char *val, struct kernel_param *kp)
 {
 	struct kparam_array *arr = kp->arg;
+	unsigned int temp_num;

 	return param_array(kp->name, val, 1, arr->max, arr->elem,
-			   arr->elemsize, arr->set, arr->num ?: &arr->max);
+			   arr->elemsize, arr->set, arr->num ?: &temp_num);
 }

 int param_array_get(char *buffer, struct kernel_param *kp)
-
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