firmware: enable run time change of forcing fallback loader
Currently one requires to test four kernel configurations to test the
firmware API completely:
0)
CONFIG_FW_LOADER=y
1)
o CONFIG_FW_LOADER=y
o CONFIG_FW_LOADER_USER_HELPER=y
2)
o CONFIG_FW_LOADER=y
o CONFIG_FW_LOADER_USER_HELPER=y
o CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y
3) When CONFIG_FW_LOADER=m the built-in stuff is disabled, we have
no current tests for this.
We can reduce the requirements to three kernel configurations by making
fw_config.force_sysfs_fallback a proc knob we flip on off. For kernels that
disable CONFIG_IKCONFIG_PROC this can also enable one to inspect if
CONFIG_FW_LOADER_USER_HELPER_FALLBACK was enabled at build time by checking
the proc value at boot time.
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c
index 9b65837..45cc409 100644
--- a/drivers/base/firmware_loader/fallback.c
+++ b/drivers/base/firmware_loader/fallback.c
@@ -7,6 +7,7 @@
#include <linux/security.h>
#include <linux/highmem.h>
#include <linux/umh.h>
+#include <linux/sysctl.h>
#include "fallback.h"
#include "firmware.h"