To be on the safe side, try to set ro_after_init data section readonly at the same time as rodata. If it fails it will likely fail again later so let's cancel module loading while we still can do it. If it doesn't fail, put it back to read-only, continue module loading and cross fingers so that it still works after module init. Then it should in principle never fail so add a WARN_ON_ONCE() to get a big fat warning in case it happens anyway. Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx> --- kernel/module/main.c | 2 +- kernel/module/strict_rwx.c | 5 ++++- 2 files changed, 5 insertions(+), 2 deletions(-) diff --git a/kernel/module/main.c b/kernel/module/main.c index 1bf4b0db291b..b603c9647e73 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -2582,7 +2582,7 @@ static noinline int do_init_module(struct module *mod) rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms); #endif ret = module_enable_rodata_ro_after_init(mod); - if (ret) + if (WARN_ON_ONCE(ret)) pr_warn("%s: %s() returned %d, ro_after_init data might still be writable\n", mod->name, __func__, ret); diff --git a/kernel/module/strict_rwx.c b/kernel/module/strict_rwx.c index f68c59974ae2..329afd43f06b 100644 --- a/kernel/module/strict_rwx.c +++ b/kernel/module/strict_rwx.c @@ -58,7 +58,10 @@ int module_enable_rodata_ro(const struct module *mod) if (ret) return ret; - return 0; + ret = module_set_memory(mod, MOD_RO_AFTER_INIT, set_memory_ro); + if (ret) + return ret; + return module_set_memory(mod, MOD_RO_AFTER_INIT, set_memory_rw); } int module_enable_rodata_ro_after_init(const struct module *mod) -- 2.44.0