[PATCH] irqchip/irq-bcm7038-l1: Prefer struct_size over open coded arithmetic

[Kees Cook]

On Fri, Feb 09, 2024 at 07:31:28PM +0100, Erick Archer wrote:
> This is an effort to get rid of all multiplications from allocation
> functions in order to prevent integer overflows [1].
> 
> As the cpu variable is a pointer to "struct bcm7038_l1_cpu" and this
> structure ends in a flexible array:
> 
> struct bcm7038_l1_cpu {
> 	void __iomem	*map_base;
> 	u32		mask_cache[];
> };
> 
> the preferred way in the kernel is to use the struct_size() helper to
> do the arithmetic instead of the argument "size + count * size" in the
> kzalloc() function.
> 
> This way, the code is more readable and more safer.
> 
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1]
> Link: https://github.com/KSPP/linux/issues/162 [2]
> 
> Signed-off-by: Erick Archer <erick.archer at gmx.com>

Yeah, looks right to me.

Reviewed-by: Kees Cook <keescook at chromium.org>

-- 
Kees Cook