6lowpan: iphc: Fix an off-by-one check of array index

The bounds check of id is off-by-one and the comparison should be >= rather >. Currently the WARN_ON_ONCE check does not stop the out of range indexing of &ldev->ctx.table[id] so also add a return path if the bounds are out of range. Addresses-Coverity: ("Illegal address computation"). Fixes: 5609c18 ("6lowpan: iphc: add support for stateful compression") Signed-off-by: Colin Ian King <[email protected]> Signed-off-by: Marcel Holtmann <[email protected]>
fracktal · Jul 22, 2021 · 9af4176 · 9af4176
1 parent 3735682
commit 9af4176
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/net/6lowpan/debugfs.c b/net/6lowpan/debugfs.c
@@ -170,7 +170,8 @@ static void lowpan_dev_debugfs_ctx_init(struct net_device *dev,
 	struct dentry *root;
 	char buf[32];
 
-	WARN_ON_ONCE(id > LOWPAN_IPHC_CTX_TABLE_SIZE);
+	if (WARN_ON_ONCE(id >= LOWPAN_IPHC_CTX_TABLE_SIZE))
+		return;
 
 	sprintf(buf, "%d", id);