From e2dc07ca4e0148d75963e14d2b78afc12426a487 Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Tue, 22 Jun 2021 13:36:41 +0200 Subject: [PATCH] module: limit enabling module.sig_enforce [ Upstream commit 0c18f29aae7ce3dadd26d8ee3505d07cc982df75 ] Irrespective as to whether CONFIG_MODULE_SIG is configured, specifying "module.sig_enforce=1" on the boot command line sets "sig_enforce". Only allow "sig_enforce" to be set when CONFIG_MODULE_SIG is configured. This patch makes the presence of /sys/module/module/parameters/sig_enforce dependent on CONFIG_MODULE_SIG=y. Fixes: fda784e50aac ("module: export module signature enforcement status") Reported-by: Nayna Jain Tested-by: Mimi Zohar Tested-by: Jessica Yu Signed-off-by: Mimi Zohar Signed-off-by: Jessica Yu Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- kernel/module.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/kernel/module.c b/kernel/module.c index 88a6a9e04f8d..59d487b8d8da 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -268,9 +268,18 @@ static void module_assert_mutex_or_preempt(void) #endif } +#ifdef CONFIG_MODULE_SIG static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE); module_param(sig_enforce, bool_enable_only, 0644); +void set_module_sig_enforced(void) +{ + sig_enforce = true; +} +#else +#define sig_enforce false +#endif + /* * Export sig_enforce kernel cmdline parameter to allow other subsystems rely * on that instead of directly to CONFIG_MODULE_SIG_FORCE config. @@ -281,11 +290,6 @@ bool is_module_sig_enforced(void) } EXPORT_SYMBOL(is_module_sig_enforced); -void set_module_sig_enforced(void) -{ - sig_enforce = true; -} - /* Block module loading/unloading? */ int modules_disabled = 0; core_param(nomodule, modules_disabled, bint, 0);