/**
* regs_get_argument_nth() - get Nth argument at function call
* @regs: pt_regs which contains registers at function entry.
* @n: argument number.
*
* regs_get_argument_nth() returns @n th argument of a function call.
* Since usually the kernel stack will be changed right after function entry,
* you must use this at function entry. If the @n th entry is NOT in the
* kernel stack or pt_regs, this returns 0.
*/
unsigned long regs_get_argument_nth(struct pt_regs *regs, unsigned int n)
{
if (n < ARRAY_SIZE(arg_offs_table))
return *(unsigned long *)((char *)regs + arg_offs_table[n]);
else {
/*
* The typical case: arg n is on the stack.
* (Note: stack[0] = return address, so skip it)
*/
n -= ARRAY_SIZE(arg_offs_table);
return regs_get_kernel_stack_nth(regs, 1 + n);
}
}
static __kprobes unsigned long fetch_stack(struct pt_regs *regs,
void *num)
{
return regs_get_kernel_stack_nth(regs,
(unsigned int)((unsigned long)num));
}
