[PATCH 5.14 036/151] module: fix clang CFI with MODULE_UNLOAD=n

Greg Kroah-Hartman
2021-10-18T13:54:40Z

From: Arnd Bergmann <arnd@arndb.de>

commit 0d67e332e6df72f43eaa21228daa3a79e23093f3 upstream.

When CONFIG_MODULE_UNLOAD is disabled, the module->exit member
is not defined, causing a build failure:

kernel/module.c:4493:8: error: no member named 'exit' in 'struct module'
mod->exit = *exit;

add an #ifdef block around this.

Fixes: cf68fffb66d6 ("add support for Clang CFI")
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
kernel/module.c | 2 ++
1 file changed, 2 insertions(+)

--- a/kernel/module.c
+++ b/kernel/module.c
@@ -4484,8 +4484,10 @@ static void cfi_init(struct module *mod)
/* Fix init/exit functions to point to the CFI jump table */
if (init)
mod->init = *init;
+#ifdef CONFIG_MODULE_UNLOAD
if (exit)
mod->exit = *exit;
+#endif

cfi_module_add(mod, module_addr_min);
#endif