Re: [PATCH] objtool: initialize all of struct elf

From: Josh Poimboeuf
Date: Thu Jun 29 2023 - 10:18:29 EST


On Thu, Jun 29, 2023 at 12:05:05PM +0200, Michal Kubecek wrote:
> Function elf_open_read() only zero initializes the initial part of
> allocated struct elf; num_relocs member was recently added outside the
> zeroed part so that it was left uninitialized, resulting in build failures
> on some systems.
>
> The partial initialization is a relic of times when struct elf had large
> hash tables embedded. This is no longer the case so remove the trap and
> initialize the whole structure instead.
>
> Fixes: eb0481bbc4ce ("objtool: Fix reloc_hash size")
> Signed-off-by: Michal Kubecek <mkubecek@xxxxxxx>
> ---
> tools/objtool/elf.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
> index d420b5d2e2b6..081befa4674b 100644
> --- a/tools/objtool/elf.c
> +++ b/tools/objtool/elf.c
> @@ -1005,7 +1005,7 @@ struct elf *elf_open_read(const char *name, int flags)
> perror("malloc");
> return NULL;
> }
> - memset(elf, 0, offsetof(struct elf, sections));
> + memset(elf, 0, sizeof(*elf));
>
> INIT_LIST_HEAD(&elf->sections);

Thanks!

Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>

--
Josh