Commit 9c53564af1

Vincent Rischmann <vincent@rischmann.fr>
2020-12-28 17:53:52
fs: fix segfault in Walker.next
`top` might point to invalid memory after a call to self.stack.append which causes a segfault. Prevent this by recomputing `top`. Fixes #7560
master
1 parent 399c428
Changed files (1)
lib
std
fs.zig
lib/std/fs.zig
@@ -2183,7 +2183,7 @@ pub const Walker = struct {
         while (true) {
             if (self.stack.items.len == 0) return null;
             // `top` becomes invalid after appending to `self.stack`.
-            const top = &self.stack.items[self.stack.items.len - 1];
+            var top = &self.stack.items[self.stack.items.len - 1];
             const dirname_len = top.dirname_len;
             if (try top.dir_it.next()) |base| {
                 self.name_buffer.shrink(dirname_len);
@@ -2200,6 +2200,7 @@ pub const Walker = struct {
                             .dir_it = new_dir.iterate(),
                             .dirname_len = self.name_buffer.items.len,
                         });
+                        top = &self.stack.items[self.stack.items.len - 1];
                     }
                 }
                 return Entry{