From 683d3f72427b39bea5827a0a1c1fc4c74dbe246e Mon Sep 17 00:00:00 2001
From: Cameron Conn <camconn@users.noreply.github.com>
Date: Mon, 1 Feb 2021 14:27:39 -0600
Subject: [PATCH] Don't read more bytes than exist in MsfStream (#7839)

---
 lib/std/pdb.zig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/std/pdb.zig b/lib/std/pdb.zig
index 41356e84f5..6a47cd6e8b 100644
--- a/lib/std/pdb.zig
+++ b/lib/std/pdb.zig
@@ -662,6 +662,7 @@ const MsfStream = struct {
 
     fn read(self: *MsfStream, buffer: []u8) !usize {
         var block_id = @intCast(usize, self.pos / self.block_size);
+        if (block_id >= self.blocks.len) return 0; // End of Stream
         var block = self.blocks[block_id];
         var offset = self.pos % self.block_size;
 
@@ -680,6 +681,7 @@ const MsfStream = struct {
             if (offset == self.block_size) {
                 offset = 0;
                 block_id += 1;
+                if (block_id >= self.blocks.len) break; // End of Stream
                 block = self.blocks[block_id];
                 try self.in_file.seekTo(block * self.block_size);
             }