Add CONFIG_MODULE_SIG_PROTECT to enable lookup for the unprotected symbols from the build time generated list of symbols. Module loading behavior will change as follows: - Allows Android GKI Modules signed using MODULE_SIG_ALL during build. - Allows other modules to load if they don't violate the access to Android GKI protected symbols. Loading will fail and return -EACCES (Permission denied) if these modules access the symbol which is not allowlisted via symbol list or exported by a GKI module. Bug: 232430739 Test: TH Signed-off-by: Ramji Jiyani <ramjiyani@google.com> Change-Id: I751b1951241b45712c20ac0e3878abd2152dd002
36 lines
932 B
C
36 lines
932 B
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Copyright 2022 Google LLC
|
|
* Author: ramjiyani@google.com (Ramji Jiyani)
|
|
*/
|
|
|
|
#include <linux/bsearch.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/printk.h>
|
|
#include <linux/string.h>
|
|
|
|
/*
|
|
* Build time generated header files
|
|
*
|
|
* gki_module_unprotected.h -- Symbols allowed to _access_ by unsigned modules
|
|
*/
|
|
#include "gki_module_unprotected.h"
|
|
|
|
/* bsearch() comparision callback */
|
|
static int cmp_name(const void *sym, const void *protected_sym)
|
|
{
|
|
return strncmp(sym, protected_sym, MAX_UNPROTECTED_NAME_LEN);
|
|
}
|
|
|
|
/**
|
|
* gki_is_module_unprotected_symbol - Is a symbol unprotected for unsigned module?
|
|
*
|
|
* @name: Symbol being checked in list of unprotected symbols
|
|
*/
|
|
bool gki_is_module_unprotected_symbol(const char *name)
|
|
{
|
|
return bsearch(name, gki_unprotected_symbols, NO_OF_UNPROTECTED_SYMBOLS,
|
|
MAX_UNPROTECTED_NAME_LEN, cmp_name) != NULL;
|
|
}
|