From: Jeff King <peff@peff.net>
Date: Thu, 24 Sep 2015 21:02:54 +0000 (-0400)
Subject: show-branch: avoid segfault with --reflog of unborn branch
X-Git-Tag: v2.8.3~32^2~26
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/7cd17e80579c2bffd6245837175a6e1b12a78045?hp=--cc

show-branch: avoid segfault with --reflog of unborn branch

When no branch is given to the "--reflog" option, we resolve
HEAD to get the default branch. However, if HEAD points to
an unborn branch, resolve_ref returns NULL, and we later
segfault trying to access it.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---

7cd17e80579c2bffd6245837175a6e1b12a78045
diff --git a/builtin/show-branch.c b/builtin/show-branch.c
index 408ce70307..092b59b0b3 100644
--- a/builtin/show-branch.c
+++ b/builtin/show-branch.c
@@ -743,6 +743,8 @@ int cmd_show_branch(int ac, const char **av, const char *prefix)
 			fake_av[1] = NULL;
 			av = fake_av;
 			ac = 1;
+			if (!*av)
+				die("no branches given, and HEAD is not valid");
 		}
 		if (ac != 1)
 			die("--reflog option needs one branch name");