firmware/lib: commit nvram before running legacy

vb2_run_altfw() can jump to run a legacy payload, so this change
adds a call to vb2_nv_commit() to commit any pending changes
to nvram before making the jump.

The call to commit requires a vb2_context, so the majority of this
change is to plumb this context through various functions.

BUG=b:124358784
BRANCH=None
TEST=local compile.  Tested with a later change that helps confirm
that a pending nvram change is written before jumping.

Change-Id: Ib32980527aa07357d62dd695a6ff479e8c918cf8
Signed-off-by: Matt Delco <delco@google.com>
Reviewed-on: https://chromium-review.googlesource.com/1504757
Reviewed-by: Julius Werner <jwerner@chromium.org>

4 files changed, 17 insertions, 11 deletions

diff --git a/firmware/lib/include/vboot_ui_common.h b/firmware/lib/include/vboot_ui_common.h
index 8998229d..17eb8151 100644
--- a/firmware/lib/include/vboot_ui_common.h
+++ b/firmware/lib/include/vboot_ui_common.h
@@ -36,9 +36,10 @@ void vb2_error_notify(const char *print_msg,
  * This will only return if it is not allowed, or the bootloader fails to
  * cannot be found / fails to start
  *
+ * @ctx		Context
  * @altfw_num	Number of bootloader to start (0=any, 1=first, etc.)
  */
-void vb2_run_altfw(enum VbAltFwIndex_t altfw_num);
+void vb2_run_altfw(struct vb2_context *ctx, enum VbAltFwIndex_t altfw_num);
 
 /** Display an error and beep to indicate that altfw is not available */
 void vb2_error_no_altfw(void);
@@ -52,9 +53,11 @@ void vb2_error_no_altfw(void);
  * If the operation is not permitted, or it is permitted but the bootloader
  * cannot be found, it beeps and returns.
  *
+ * @ctx		Context
  * @allowed	1 if allowed, 0 if not allowed
  * @altfw_num	Number of bootloader to start (0=any, 1=first, etc.)
  */
-void vb2_try_alt_fw(int allowed, enum VbAltFwIndex_t altfw_num);
+void vb2_try_alt_fw(struct vb2_context *ctx, int allowed,
+		    enum VbAltFwIndex_t altfw_num);
 
 #endif  /* VBOOT_REFERENCE_VBOOT_UI_COMMON_H_ */
diff --git a/firmware/lib/vboot_ui.c b/firmware/lib/vboot_ui.c
index 5a663c29..6d19a164 100644
--- a/firmware/lib/vboot_ui.c
+++ b/firmware/lib/vboot_ui.c
@@ -206,7 +206,7 @@ VbError_t vb2_altfw_ui(struct vb2_context *ctx)
 			 * This will not return if successful. Drop out to
 			 * developer mode on failure.
 			 */
-			vb2_run_altfw(key - '0');
+			vb2_run_altfw(ctx, key - '0');
 			active = 0;
 			break;
 		default:
@@ -612,7 +612,7 @@ VbError_t vb2_developer_ui(struct vb2_context *ctx)
 			VB2_DEBUG("VbBootDeveloper() - "
 				  "user pressed key '%c': Boot alternative "
 				  "firmware\n", key);
-			vb2_try_alt_fw(allow_legacy, key - '0');
+			vb2_try_alt_fw(ctx, allow_legacy, key - '0');
 			break;
 		default:
 			VB2_DEBUG("VbBootDeveloper() - pressed key %d\n", key);
@@ -628,7 +628,7 @@ VbError_t vb2_developer_ui(struct vb2_context *ctx)
 	/* If defaulting to legacy boot, try that unless Ctrl+D was pressed */
 	if (use_legacy && !ctrl_d_pressed) {
 		VB2_DEBUG("VbBootDeveloper() - defaulting to legacy\n");
-		vb2_try_alt_fw(allow_legacy, 0);
+		vb2_try_alt_fw(ctx, allow_legacy, 0);
 	}
 
 	if ((use_usb && !ctrl_d_pressed) && allow_usb) {
diff --git a/firmware/lib/vboot_ui_common.c b/firmware/lib/vboot_ui_common.c
index 01201ca5..be5d1f24 100644
--- a/firmware/lib/vboot_ui_common.c
+++ b/firmware/lib/vboot_ui_common.c
@@ -12,6 +12,7 @@
 
 #include "rollback_index.h"
 #include "vboot_api.h"
+#include "vboot_kernel.h"
 #include "vboot_ui_common.h"
 
 /* One or two beeps to notify that attempted action was disallowed. */
@@ -43,12 +44,13 @@ void vb2_error_notify(const char *print_msg,
 	vb2_error_beep(beep);
 }
 
-void vb2_run_altfw(enum VbAltFwIndex_t altfw_num)
+void vb2_run_altfw(struct vb2_context *ctx, enum VbAltFwIndex_t altfw_num)
 {
 	if (RollbackKernelLock(0)) {
 		vb2_error_notify("Error locking kernel versions on legacy "
 				 "boot.\n", NULL, VB_BEEP_FAILED);
 	} else {
+		vb2_nv_commit(ctx);
 		VbExLegacy(altfw_num);	/* will not return if found */
 		vb2_error_notify("Legacy boot failed. Missing BIOS?\n", NULL,
 				 VB_BEEP_FAILED);
@@ -64,10 +66,11 @@ void vb2_error_no_altfw(void)
 	vb2_error_beep(VB_BEEP_NOT_ALLOWED);
 }
 
-void vb2_try_alt_fw(int allowed, enum VbAltFwIndex_t altfw_num)
+void vb2_try_alt_fw(struct vb2_context *ctx, int allowed,
+		    enum VbAltFwIndex_t altfw_num)
 {
 	if (allowed)
-		vb2_run_altfw(altfw_num);	/* will not return if found */
+		vb2_run_altfw(ctx, altfw_num);	/* will not return if found */
 	else
 		vb2_error_no_altfw();
 }
diff --git a/firmware/lib/vboot_ui_menu.c b/firmware/lib/vboot_ui_menu.c
index 17c1137e..5ac4bb40 100644
--- a/firmware/lib/vboot_ui_menu.c
+++ b/firmware/lib/vboot_ui_menu.c
@@ -162,7 +162,7 @@ static VbError_t boot_legacy_action(struct vb2_context *ctx)
 		return VBERROR_KEEP_LOOPING;
 	}
 
-	vb2_run_altfw(VB_ALTFW_DEFAULT);
+	vb2_run_altfw(ctx, VB_ALTFW_DEFAULT);
 	vb2_flash_screen(ctx);
 	return VBERROR_KEEP_LOOPING;
 }
@@ -342,7 +342,7 @@ static VbError_t language_action(struct vb2_context *ctx)
 /* Action when selecting a bootloader in the alternative firmware menu. */
 static VbError_t altfw_action(struct vb2_context *ctx)
 {
-	vb2_run_altfw(current_menu_idx + 1);
+	vb2_run_altfw(ctx, current_menu_idx + 1);
 	vb2_flash_screen(ctx);
 	VB2_DEBUG(no_legacy);
 	VbExDisplayDebugInfo(no_legacy, 0);
@@ -797,7 +797,7 @@ static VbError_t vb2_developer_menu(struct vb2_context *ctx)
 			VB2_DEBUG("VbBootDeveloper() - "
 				  "user pressed key '%c': Boot alternative "
 				  "firmware\n", key);
-			vb2_try_alt_fw(altfw_allowed, key - '0');
+			vb2_try_alt_fw(ctx, altfw_allowed, key - '0');
 			break;
 		default:
 			ret = vb2_handle_menu_input(ctx, key, 0);