On Wed, 30 Oct 2024 09:14:49 -0700
Nathan Chancellor <nat...@kernel.org> wrote:
> __get_insn_slot() allocates 'struct kprobe_insn_page' using a custom
> structure size calculation macro, KPROBE_INSN_PAGE_SIZE. Replace
> KPROBE_INSN_PAGE_SIZE with the struct_size() macro, which is the
> preferred way to calculate the size of flexible structures in the kernel
> because it handles overflow and makes it easier to change and audit how
> flexible structures are allocated across the entire tree.
>
But I like this patch. I'll pick this.
Thank you!
> Signed-off-by: Nathan Chancellor <nat...@kernel.org>
> ---
> kernel/kprobes.c | 6 +-----
> 1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/kernel/kprobes.c b/kernel/kprobes.c
> index
> 2cf4628bc97ce2ae18547b513cd75b6350e9cc9c..d452e784b31fa69042229ce0f5ffff9d8b671e92
> 100644
> --- a/kernel/kprobes.c
> +++ b/kernel/kprobes.c
> @@ -95,10 +95,6 @@ struct kprobe_insn_page {
> char slot_used[] __counted_by(nused);
> };
>
> -#define KPROBE_INSN_PAGE_SIZE(slots) \
> - (offsetof(struct kprobe_insn_page, slot_used) + \
> - (sizeof(char) * (slots)))
> -
> static int slots_per_page(struct kprobe_insn_cache *c)
> {
> return PAGE_SIZE/(c->insn_size * sizeof(kprobe_opcode_t));
> @@ -177,7 +173,7 @@ kprobe_opcode_t *__get_insn_slot(struct kprobe_insn_cache
> *c)
> goto retry;
>
> /* All out of space. Need to allocate a new page. */
> - kip = kmalloc(KPROBE_INSN_PAGE_SIZE(num_slots), GFP_KERNEL);
> + kip = kmalloc(struct_size(kip, slot_used, num_slots), GFP_KERNEL);
> if (!kip)
> goto out;
>
>
> --
> 2.47.0
>
--
Masami Hiramatsu (Google) <mhira...@kernel.org>
