raise error if a TLS struct does not fit
diff --git a/include/picotls.h b/include/picotls.h
index e0c3908..98dbe13 100644
--- a/include/picotls.h
+++ b/include/picotls.h
@@ -248,6 +248,7 @@
#define PTLS_ERROR_REJECT_EARLY_DATA (PTLS_ERROR_CLASS_INTERNAL + 9)
#define PTLS_ERROR_DELEGATE (PTLS_ERROR_CLASS_INTERNAL + 10)
#define PTLS_ERROR_ASYNC_OPERATION (PTLS_ERROR_CLASS_INTERNAL + 11)
+#define PTLS_ERROR_BLOCK_OVERFLOW (PTLS_ERROR_CLASS_INTERNAL + 12)
#define PTLS_ERROR_INCORRECT_BASE64 (PTLS_ERROR_CLASS_INTERNAL + 50)
#define PTLS_ERROR_PEM_LABEL_NOT_FOUND (PTLS_ERROR_CLASS_INTERNAL + 51)
@@ -1203,6 +1204,10 @@
} while (0); \
size_t body_size = (buf)->off - body_start; \
if (capacity != -1) { \
+ if (body_size >= (size_t)1 << (capacity * 8)) { \
+ ret = PTLS_ERROR_BLOCK_OVERFLOW; \
+ goto Exit; \
+ } \
for (; capacity != 0; --capacity) \
(buf)->base[body_start - capacity] = (uint8_t)(body_size >> (8 * (capacity - 1))); \
} else { \
