[Minor] Add array allocation methods to handle integer overflow

diff --git a/src/libutil/mem_pool.c b/src/libutil/mem_pool.c
index ac0a28e02f7eb96d3344d2a03051a49e97a8983c..d58be5e08cd43e02b95265ea5b3f80932f3381d7 100644 (file)
--- a/src/libutil/mem_pool.c
+++ b/src/libutil/mem_pool.c
@@ -559,6 +559,25 @@ rspamd_mempool_alloc_ (rspamd_mempool_t * pool, gsize size, gsize alignment, con
        return memory_pool_alloc_common (pool, size, alignment, RSPAMD_MEMPOOL_NORMAL, loc);
 }
 
+/*
+ * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX
+ * if both s1 < MUL_NO_OVERFLOW and s2 < MUL_NO_OVERFLOW
+ */
+#define MUL_NO_OVERFLOW        (1UL << (sizeof(gsize) * 4))
+
+void *
+rspamd_mempool_alloc_array_ (rspamd_mempool_t * pool,  gsize nmemb, gsize size, gsize alignment, const gchar *loc)
+{
+       if ((nmemb >= MUL_NO_OVERFLOW || size >= MUL_NO_OVERFLOW) &&
+               nmemb > 0 && G_MAXSIZE / nmemb < size) {
+
+               g_error("alloc_array: overflow %"G_GSIZE_FORMAT" * %"G_GSIZE_FORMAT"",
+                               nmemb, size);
+               g_abort();
+       }
+       return memory_pool_alloc_common (pool, size, alignment, RSPAMD_MEMPOOL_NORMAL, loc);
+}
+
 void *
 rspamd_mempool_alloc0_ (rspamd_mempool_t * pool, gsize size, gsize alignment, const gchar *loc)
 {

diff --git a/src/libutil/mem_pool.h b/src/libutil/mem_pool.h
index 207f5031bdae72506ed89e4c27ed6775f53f41c4..0ca1d3905ab81f9a2b3b71caa6e525b19c97fe07 100644 (file)
--- a/src/libutil/mem_pool.h
+++ b/src/libutil/mem_pool.h
@@ -154,8 +154,23 @@ rspamd_mempool_t *rspamd_mempool_new_ (gsize size, const gchar *tag, gint flags,
  */
 void *rspamd_mempool_alloc_ (rspamd_mempool_t *pool, gsize size, gsize alignment, const gchar *loc)
        RSPAMD_ATTR_ALLOC_SIZE(2) RSPAMD_ATTR_ALLOC_ALIGN(MIN_MEM_ALIGNMENT) RSPAMD_ATTR_RETURNS_NONNUL;
+/**
+ * Allocates array handling potential integer overflow
+ * @param pool
+ * @param nmemb
+ * @param size
+ * @param alignment
+ * @param loc
+ * @return
+ */
+void *rspamd_mempool_alloc_array_ (rspamd_mempool_t *pool, gsize nmemb, gsize size, gsize alignment, const gchar *loc)
+RSPAMD_ATTR_ALLOC_SIZE(2) RSPAMD_ATTR_ALLOC_ALIGN(MIN_MEM_ALIGNMENT) RSPAMD_ATTR_RETURNS_NONNUL;
 #define rspamd_mempool_alloc(pool, size) \
        rspamd_mempool_alloc_((pool), (size), MIN_MEM_ALIGNMENT, (G_STRLOC))
+#define rspamd_mempool_alloc_array(pool, nmemb, size) \
+       rspamd_mempool_alloc_array_((pool), (nmemb), (size), MIN_MEM_ALIGNMENT, (G_STRLOC))
+#define rspamd_mempool_alloc_array_type(pool, nmemb, type) \
+       (type *)rspamd_mempool_alloc_array_((pool), (nmemb), sizeof(type), MIN_MEM_ALIGNMENT, (G_STRLOC))
 #define rspamd_mempool_alloc_type(pool, type) \
        (type *)(rspamd_mempool_alloc_((pool), sizeof(type), \
        MAX(MIN_MEM_ALIGNMENT, RSPAMD_ALIGNOF(type)), (G_STRLOC)))