util/hash_table: Fix hashing in clears on 32-bit
authorTomeu Vizoso <tomeu.vizoso@collabora.com>
Mon, 5 Aug 2019 09:22:49 +0000 (11:22 +0200)
committerTomeu Vizoso <tomeu.vizoso@collabora.com>
Thu, 8 Aug 2019 05:42:52 +0000 (07:42 +0200)
Some hash functions (eg. key_u64_hash) will attempt to dereference the
key, causing an invalid access when passed DELETED_KEY_VALUE (0x1) or
FREED_KEY_VALUE (0x0).

When in 32-bit arch a 64-bit key value doesn't fit into a pointer, so
hash_table_u64 internally use a pointer to a struct containing the
64-bit key value.

Fix _mesa_hash_table_u64_clear() to handle the 32-bit case by creating a
temporary hash_key_u64 to pass to the hash function.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Suggested-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Cc: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Cc: Nicolai Hähnle <nicolai.haehnle@amd.com>
src/util/hash_table.c

index f58575de558f174ecba4d8083cefb29152b21403..58e6fc2d91691a3cafb07b0201cb1771db6478d8 100644 (file)
@@ -667,7 +667,12 @@ _mesa_hash_table_u64_clear(struct hash_table_u64 *ht,
          struct hash_entry entry;
 
          /* Create a fake entry for the delete function. */
-         entry.hash = table->key_hash_function(table->deleted_key);
+         if (sizeof(void *) == 8) {
+            entry.hash = table->key_hash_function(table->deleted_key);
+         } else {
+            struct hash_key_u64 _key = { .value = (uintptr_t)table->deleted_key };
+            entry.hash = table->key_hash_function(&_key);
+         }
          entry.key = table->deleted_key;
          entry.data = ht->deleted_key_data;
 
@@ -682,7 +687,12 @@ _mesa_hash_table_u64_clear(struct hash_table_u64 *ht,
          struct hash_entry entry;
 
          /* Create a fake entry for the delete function. */
-         entry.hash = table->key_hash_function(uint_key(FREED_KEY_VALUE));
+         if (sizeof(void *) == 8) {
+            entry.hash = table->key_hash_function(uint_key(FREED_KEY_VALUE));
+         } else {
+            struct hash_key_u64 _key = { .value = (uintptr_t)FREED_KEY_VALUE };
+            entry.hash = table->key_hash_function(&_key);
+         }
          entry.key = uint_key(FREED_KEY_VALUE);
          entry.data = ht->freed_key_data;