From 2045a5018b079d956176e7677bfab9d1fd63dae5 Mon Sep 17 00:00:00 2001
From: Michal <18419007+m-rola@users.noreply.github.com>
Date: Tue, 15 Sep 2026 10:32:31 +0200
Subject: [PATCH] fix(issue-732): Add bounds check before native compress to
 prevent buffer overflow (#732)

---
 src/main/java/org/xerial/snappy/Snappy.java     |  7 +++++++
 src/test/java/org/xerial/snappy/SnappyTest.java | 15 +++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/src/main/java/org/xerial/snappy/Snappy.java b/src/main/java/org/xerial/snappy/Snappy.java
index 14d17964..7613e7f7 100755
--- a/src/main/java/org/xerial/snappy/Snappy.java
+++ b/src/main/java/org/xerial/snappy/Snappy.java
@@ -150,6 +150,13 @@ public static int compress(ByteBuffer uncompressed, ByteBuffer compressed)
         int uPos = uncompressed.position();
         int uLen = uncompressed.remaining();
         int cPos = compressed.position();
+
+        int requiredCapacity = maxCompressedLength(uLen);
+        if (compressed.remaining() < requiredCapacity) {
+            throw new IllegalArgumentException("not enough space for output: need " + requiredCapacity
+                    + " bytes, but only " + compressed.remaining() + " remaining");
+        }
+
         int compressedSize = impl.rawCompress(uncompressed, uPos, uLen, compressed,
                 cPos);
 
diff --git a/src/test/java/org/xerial/snappy/SnappyTest.java b/src/test/java/org/xerial/snappy/SnappyTest.java
index 52c3a005..34bd8e4d 100755
--- a/src/test/java/org/xerial/snappy/SnappyTest.java
+++ b/src/test/java/org/xerial/snappy/SnappyTest.java
@@ -527,6 +527,21 @@ public void isTooLargeShortArrayInputLengthForBitShuffleShuffle() throws Excepti
         BitShuffle.shuffle(new short[Integer.MAX_VALUE / 2 + 1]);
     }
 
+    @Test(expected = IllegalArgumentException.class)
+    public void testCompressWithInsufficientBuffer() throws Exception {
+        byte[] incompressible = new byte[1024 * 1024];
+        new java.util.Random(42).nextBytes(incompressible);
+
+        ByteBuffer src = ByteBuffer.allocateDirect(incompressible.length);
+        src.put(incompressible);
+        src.flip();
+
+        ByteBuffer dest = ByteBuffer.allocateDirect(64);
+
+        Snappy.compress(src, dest);
+        fail("Expected IllegalArgumentException but method completed normally");
+}
+
     private void assumingCIIsFalse() {
         if (System.getenv("CI") == null)
             return;