Subject: Re: linux-next: manual merge of the livepatching tree with the modules tree

From: Stephen Rothwell <[email-masked]>
Date: Fri, 5 Jun 2020 14:45:57 +1000

Hi all,

On Fri, 8 May 2020 18:05:24 +1000 Stephen Rothwell <[email-masked]> wrote:
>
> Today's linux-next merge of the livepatching tree got a conflict in:
> 
>   kernel/module.c
> 
> between commits:
> 
>   db991af02f11 ("module: break nested ARCH_HAS_STRICT_MODULE_RWX and STRICT_MODULE_RWX #ifdefs")
>   5c3a7db0c7ec ("module: Harden STRICT_MODULE_RWX")
> 
> from the modules tree and commit:
> 
>   e6eff4376e28 ("module: Make module_enable_ro() static again")
> 
> from the livepatching tree.
> 
> diff --cc kernel/module.c
> index c69291362676,a26343ea4d50..000000000000
> --- a/kernel/module.c
> +++ b/kernel/module.c
> @@@ -2055,29 -2023,20 +2042,30 @@@ static void module_enable_nx(const stru
>   	frob_writable_data(&mod->init_layout, set_memory_nx);
>   }
>   
>  +static int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
>  +				       char *secstrings, struct module *mod)
>  +{
>  +	const unsigned long shf_wx = SHF_WRITE|SHF_EXECINSTR;
>  +	int i;
>  +
>  +	for (i = 0; i < hdr->e_shnum; i++) {
>  +		if ((sechdrs[i].sh_flags & shf_wx) == shf_wx)
>  +			return -ENOEXEC;
>  +	}
>  +
>  +	return 0;
>  +}
>  +
>   #else /* !CONFIG_STRICT_MODULE_RWX */
>  +/* module_{enable,disable}_ro() stubs are in module.h */
>   static void module_enable_nx(const struct module *mod) { }
> + static void module_enable_ro(const struct module *mod, bool after_init) {}
>  -#endif /*  CONFIG_STRICT_MODULE_RWX */
>  -static void module_enable_x(const struct module *mod)
>  +static int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
>  +				       char *secstrings, struct module *mod)
>   {
>  -	frob_text(&mod->core_layout, set_memory_x);
>  -	frob_text(&mod->init_layout, set_memory_x);
>  +	return 0;
>   }
>  -#else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
>  -static void module_enable_nx(const struct module *mod) { }
>  -static void module_enable_x(const struct module *mod) { }
>  -#endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
>  -
>  +#endif /*  CONFIG_STRICT_MODULE_RWX */
>   
>   #ifdef CONFIG_LIVEPATCH
>   /*

This is now a conflict between the modules tree and Linus' tree.

-- 
Cheers,
Stephen Rothwell