MONGOCRYPT-924 Improve arithmetic type consistency when computing metadata_len (#1183)

eramongodb · web-flow · commit 74df5a264d66 · 2026-05-26T15:29:41.000-05:00
diff --git a/src/mc-fle2-payload-iev-v2.c b/src/mc-fle2-payload-iev-v2.c
@@ -600,9 +600,8 @@ bool mc_FLE2IndexedEncryptedValueV2_parse(mc_FLE2IndexedEncryptedValueV2_t *iev,
         }
     }
 
-    // Maximum edge_count(4294967295) times kMetadataLen(96) fits easily without
-    // overflow.
-    const uint64_t metadata_len = iev->edge_count * kMetadataLen;
+    // Maximum edge_count(4294967295) times kMetadataLen(96) fits easily without overflowing uint64.
+    const uint64_t metadata_len = (uint64_t)iev->edge_count * (uint64_t)kMetadataLen;
 
     /* Read ServerEncryptedValue. */
     const uint64_t min_required_len = kMinServerEncryptedValueLen + metadata_len;

Original file line number	Diff line number	Diff line change
`@@ -600,9 +600,8 @@ bool mc_FLE2IndexedEncryptedValueV2_parse(mc_FLE2IndexedEncryptedValueV2_t *iev,`
`600`	`600`	`}`
`601`	`601`	`}`
`602`	`602`
`603`		`- // Maximum edge_count(4294967295) times kMetadataLen(96) fits easily without`
`604`		`- // overflow.`
`605`		`- const uint64_t metadata_len = iev->edge_count * kMetadataLen;`
	`603`	`+ // Maximum edge_count(4294967295) times kMetadataLen(96) fits easily without overflowing uint64.`
	`604`	`+ const uint64_t metadata_len = (uint64_t)iev->edge_count * (uint64_t)kMetadataLen;`
`606`	`605`
`607`	`606`	`/* Read ServerEncryptedValue. */`
`608`	`607`	`const uint64_t min_required_len = kMinServerEncryptedValueLen + metadata_len;`