Commit f9231a99 authored by Nicholas Piggin's avatar Nicholas Piggin Committed by Michael Ellerman
Browse files

module: add module_elf_check_arch for module-specific checks 



The elf_check_arch() function is also used to test compatibility of
usermode binaries. Kernel modules may have more specific requirements,
for example powerpc would like to test for ABI version compatibility.

Add a weak module_elf_check_arch() that defaults to true, and call it
from elf_validity_check().

Signed-off-by: default avatarJessica Yu <jeyu@kernel.org>
[np: added changelog, adjust name, rebase]
Acked-by: default avatarLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: default avatarNicholas Piggin <npiggin@gmail.com>
Reviewed-by: default avatarJoel Stanley <joel@jms.id.au>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221128041539.1742489-2-npiggin@gmail.com
parent 2f228ee1

include/linux/moduleloader.h

+3 −0
Original line number Diff line number Diff line
@@ -13,6 +13,9 @@ 
 * must be implemented by each architecture.

 */



/* arch may override to do additional checking of ELF header architecture */

bool module_elf_check_arch(Elf_Ehdr *hdr);



/* Adjust arch-specific sections.  Return 0 on success.  */

int module_frob_arch_sections(Elf_Ehdr *hdr,

			      Elf_Shdr *sechdrs,

kernel/module/main.c

+10 −0
Original line number Diff line number Diff line
@@ -1674,6 +1674,11 @@ static int elf_validity_check(struct load_info *info) 
		       info->hdr->e_machine);

		goto no_exec;

	}

	if (!module_elf_check_arch(info->hdr)) {

		pr_err("Invalid module architecture in ELF header: %u\n",

		       info->hdr->e_machine);

		goto no_exec;

	}

	if (info->hdr->e_shentsize != sizeof(Elf_Shdr)) {

		pr_err("Invalid ELF section header size\n");

		goto no_exec;
@@ -2247,6 +2252,11 @@ static void flush_module_icache(const struct module *mod) 
			   (unsigned long)mod->core_layout.base + mod->core_layout.size);

}



bool __weak module_elf_check_arch(Elf_Ehdr *hdr)

{

	return true;

}



int __weak module_frob_arch_sections(Elf_Ehdr *hdr,

				     Elf_Shdr *sechdrs,

				     char *secstrings,