fix: enforce the analysis image cap while reading, not after

The OCR and vision dispatchers read the whole page image into a Vec via
storage.get() and only then checked max_image_bytes, so the cap couldn't
bound the read. Stream via get_stream() + safety::accumulate_capped so the
read bails as soon as the running total exceeds the cap.

Bump to 0.124.6.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

backend/Cargo.lock

@@ -1558,7 +1558,7 @@ checksum = "c41e0c4fef86961ac6d6f8a82609f55f31b05e4fce149ac5710e439df7619ba4"
 
 [[package]]
 name = "mangalord"
-version = "0.124.5"
+version = "0.124.6"
 dependencies = [
  "anyhow",
  "argon2",

backend/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "mangalord"
-version = "0.124.5"
+version = "0.124.6"
 edition = "2021"
 default-run = "mangalord"
 

backend/src/analysis/daemon.rs

@@ -393,19 +393,20 @@ impl AnalyzeDispatcher for RealAnalyzeDispatcher {
             // Page was deleted between enqueue and dispatch — nothing to do.
             return Ok(());
         };
-        let bytes = self
+        // Stream through the byte cap so an oversized blob is rejected as it's
+        // read rather than after it's fully buffered into memory (mirrors the
+        // OCR dispatcher).
+        let file = self
             .storage
-            .get(&page.storage_key)
+            .get_stream(&page.storage_key)
             .await
             .map_err(|e| anyhow::anyhow!("read page image {}: {e}", page.storage_key))?;
-        if bytes.len() > self.max_image_bytes {
-            anyhow::bail!(
-                "page image {} is {} bytes, over the {} cap",
-                page.storage_key,
-                bytes.len(),
-                self.max_image_bytes
-            );
-        }
+        let bytes =
+            crate::crawler::safety::accumulate_capped(file.stream, self.max_image_bytes)
+                .await
+                .map_err(|e| {
+                    anyhow::anyhow!("page image {} over the byte cap: {e}", page.storage_key)
+                })?;
         let analysis = self.vision.analyze(&bytes, &page.content_type).await?;
         repo::page_analysis::persist_analysis(&self.db, page_id, &analysis, &self.model).await?;
         Ok(())

backend/src/analysis/ocr.rs

@@ -207,19 +207,21 @@ impl AnalyzeDispatcher for OcrAnalyzeDispatcher {
             // Page was deleted between enqueue and dispatch — nothing to do.
             return Ok(());
         };
-        let bytes = self
+        // Stream the blob through the byte cap so the read itself bails once
+        // the running total exceeds `max_image_bytes` — a plain `get()` would
+        // buffer the whole (possibly huge) image into memory before the cap
+        // could reject it.
+        let file = self
             .storage
-            .get(&page.storage_key)
+            .get_stream(&page.storage_key)
             .await
             .map_err(|e| anyhow::anyhow!("read page image {}: {e}", page.storage_key))?;
-        if bytes.len() > self.max_image_bytes {
-            anyhow::bail!(
-                "page image {} is {} bytes, over the {} cap",
-                page.storage_key,
-                bytes.len(),
-                self.max_image_bytes
-            );
-        }
+        let bytes =
+            crate::crawler::safety::accumulate_capped(file.stream, self.max_image_bytes)
+                .await
+                .map_err(|e| {
+                    anyhow::anyhow!("page image {} over the byte cap: {e}", page.storage_key)
+                })?;
         // OCR inference is CPU-bound and synchronous — keep it off the async
         // worker's runtime thread, and gate it behind the shared permit pool so
         // ANALYSIS_WORKERS > cores can't oversubscribe the blocking pool.

backend/tests/analysis_ocr.rs

@@ -99,6 +99,36 @@ async fn dispatch_persists_ocr_lines_and_search_doc(pool: PgPool) {
     assert!(has_doc, "search_doc must be populated from OCR text");
 }
 
+#[sqlx::test(migrations = "./migrations")]
+async fn dispatch_rejects_page_image_over_the_byte_cap(pool: PgPool) {
+    let dir = TempDir::new().unwrap();
+    let storage: Arc<dyn Storage> = Arc::new(LocalStorage::new(dir.path()));
+    let key = "mangas/x/big.png";
+    // 4 KiB on disk, 1 KiB cap — the streamed read must bail on the cap
+    // rather than buffering the whole blob and OCR-ing it.
+    storage.put(key, &vec![0u8; 4096]).await.unwrap();
+    let page_id = seed_page(&pool, key).await;
+
+    let dispatcher = OcrAnalyzeDispatcher {
+        db: pool.clone(),
+        storage: Arc::clone(&storage),
+        engine: StubOcrEngine::new(&["should not run"]),
+        max_image_bytes: 1024,
+        ocr_permits: Arc::new(tokio::sync::Semaphore::new(1)),
+    };
+    let err = dispatcher.dispatch(page_id).await.unwrap_err();
+    assert!(
+        err.chain().any(|c| c.to_string().contains("cap")),
+        "expected an over-cap error, got: {err:#}"
+    );
+
+    // A rejected page must not land an analysis row.
+    assert!(repo::page_analysis::load(&pool, page_id)
+        .await
+        .unwrap()
+        .is_none());
+}
+
 #[sqlx::test(migrations = "./migrations")]
 async fn dispatch_missing_page_is_noop(pool: PgPool) {
     let dir = TempDir::new().unwrap();

frontend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "mangalord-frontend",
-  "version": "0.124.5",
+  "version": "0.124.6",
   "private": true,
   "type": "module",
   "scripts": {