Commit 31143a12 authored by Bert Wesarg's avatar Bert Wesarg Committed by Linus Torvalds
Browse files

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

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.


# 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
$ echo "4,3,2,1" > /sys/module/example/parameters/array
$ dmesg | tail -n 1
kernel: array: can take only 3 arguments
Signed-off-by: default avatarBert Wesarg <>
Signed-off-by: default avatarAndrew Morton <>
Signed-off-by: default avatarLinus Torvalds <>
parent fc9c9ab2
......@@ -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)
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment