Re: [PATCH RFC 2/4] sh/crash_dump: check ioremap() in copy_oldmem_page()

[Geert Uytterhoeven]

On Thu, 12 Nov 2026 at 17:43, Christian Brauner <brauner@xxxxxxxxxx> wrote:
> copy_oldmem_page() maps a page of the old kernel with ioremap() and
> copies from it without checking whether the mapping worked. If it
> didn't, the copy reads from an offset into the NULL page.
>
> Return -ENOMEM like the other architectures do. read_from_oldmem() turns
> that into -EFAULT like any other short copy.
>
> Fixes: 4d5ade5b29c6 ("sh: kdump support.")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Christian Brauner (Amutable) <brauner@xxxxxxxxxx>

Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds