From: Stefan Sperling <stsp@stsp.name>
Subject: Re: got/tog segfault with corrupted (?) checkout
To: Theo Buehler <tb@theobuehler.org>
Cc: Matthias Schmidt <openbsd@xosc.org>, gameoftrees@openbsd.org
Date: Wed, 27 Dec 2023 13:22:48 +0100

On Wed, Dec 27, 2023 at 01:13:22PM +0100, Theo Buehler wrote:
> does /usr/ports/.got/base_commit happen to be empty?

Yes, the problem can be reproduced with these steps:

  $ rm .got/base-commit
  $ touch .got/base-commit
  $ got up
  Segmentation fault (core dumped)

Below is the obvious fix:

  $ got up
  got: /tmp/test-wt/.got/base-commit: bad worktree meta data

diff /home/stsp/src/got
commit - 1e63031fcde1dee62ea14a73d4bf3638632e691b
path + /home/stsp/src/got
blob - cbce00f57c0999cd56f639776fdc0be83f732cf9
file + lib/worktree_open.c
--- lib/worktree_open.c
+++ lib/worktree_open.c
@@ -80,6 +80,10 @@ read_meta_file(char **content, const char *path_got, c
 		err = got_error_from_errno2("fstat", path);
 		goto done;
 	}
+	if (sb.st_size == 0) {
+		err = got_error_path(path, GOT_ERR_WORKTREE_META);
+		goto done;
+	}
 	*content = calloc(1, sb.st_size);
 	if (*content == NULL) {
 		err = got_error_from_errno("calloc");