fixup! fixup! fixup! sys/{riotboot,suit}: allow updates without boot header

Author: fabian18

sys/riotboot/flashwrite.c

@@ -132,14 +132,14 @@ int riotboot_flashwrite_putbytes(riotboot_flashwrite_t *state,
         flashpage_avail -= to_copy;
         if ((!flashpage_avail) || (!more)) {
 #if CONFIG_RIOTBOOT_FLASHWRITE_RAW  /* Guards access to state::firstblock_buf */
-            void *addr = flashpage_addr(state->flashpage);
             if (!state->offset) {
                 /* Skip flashing the first block, store it for later to flash it
                  * during the flashwrite_finish function, when payload contains the boot header */
                 memcpy(state->firstblock_buf,
                        state->flashpage_buf, RIOTBOOT_FLASHPAGE_BUFFER_SIZE);
             }
             else {
+                void *addr = flashpage_addr(state->flashpage);
                 flashpage_write((uint8_t *)addr + flashpage_pos,
                                 state->flashpage_buf,
                                 RIOTBOOT_FLASHPAGE_BUFFER_SIZE);
@@ -209,18 +209,14 @@ int riotboot_flashwrite_finish_raw(riotboot_flashwrite_t *state,
     uint8_t *slot_start = (uint8_t *)riotboot_slot_get_hdr(state->target_slot);
     const uint8_t *data = bytes;
     size_t remaining = len;
-    size_t to_copy;
+    size_t to_copy = MIN(remaining, sizeof(state->flashpage_buf));
 
     if (!state->skip_len) {
 #if IS_ACTIVE(CONFIG_RIOTBOOT_FLASHWRITE_RAW)
         /* If there is a skip_len, the first block contains the header and must be
          * re-flashed to include the magic number and checksum. */
-        to_copy = MIN(remaining, sizeof(state->firstblock_buf));
         memcpy(state->firstblock_buf, data, to_copy);
-        flashpage_write(slot_start, state->firstblock_buf,
-                        RIOTBOOT_FLASHPAGE_BUFFER_SIZE);
-        data += to_copy;
-        remaining -= to_copy;
+        memcpy(state->flashpage_buf, state->firstblock_buf, sizeof(state->flashpage_buf));
 #endif
     }
     while (remaining) {

sys/suit/storage/flashwrite.c

@@ -82,7 +82,7 @@ static int _flashwrite_write(suit_storage_t *storage,
             fw->writer.offset = RIOTBOOT_HDR_LEN;
             fw->writer.skip_len = RIOTBOOT_HDR_LEN;
         }
-        memset(fw->writer.flashpage_buf, 0xff, sizeof(fw->writer.flashpage_buf));
+        memset(fw->writer.flashpage_buf, FLASHPAGE_ERASE_STATE, sizeof(fw->writer.flashpage_buf));
     }
     else if (offset != fw->writer.offset - fw->writer.skip_len) {
         LOG_ERROR("Unexpected offset: %u - expected: %u\n", (unsigned)offset,