From afe5d3d516114f08d3c4289682a704f5a7889909 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Thu, 29 Jan 2009 03:33:02 -0500 Subject: symbolic ref: refuse non-ref targets in HEAD When calling "git symbolic-ref" it is easy to forget that the target must be a fully qualified ref. E.g., you might accidentally do: $ git symbolic-ref HEAD master Unfortunately, this is very difficult to recover from, because the bogus contents of HEAD make git believe we are no longer in a git repository (as is_git_dir explicitly checks for "^refs/heads/" in the HEAD target). So immediately trying to fix the situation doesn't work: $ git symbolic-ref HEAD refs/heads/master fatal: Not a git repository and one is left editing the .git/HEAD file manually. Furthermore, one might be tempted to use symbolic-ref to set up a detached HEAD: $ git symbolic-ref HEAD `git rev-parse HEAD` which sets up an even more bogus HEAD: $ cat .git/HEAD ref: 1a9ace4f2ad4176148e61b5a85cd63d5604aac6d This patch introduces a small safety valve to prevent the specific case of anything not starting with refs/heads/ to go into HEAD. The scope of the safety valve is intentionally very limited, to make sure that we are not preventing any behavior that would otherwise be valid (like pointing a different symref than HEAD outside of refs/heads/). Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- builtin-symbolic-ref.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'builtin-symbolic-ref.c') diff --git a/builtin-symbolic-ref.c b/builtin-symbolic-ref.c index bfc78bb3f..cafc4eba7 100644 --- a/builtin-symbolic-ref.c +++ b/builtin-symbolic-ref.c @@ -44,6 +44,9 @@ int cmd_symbolic_ref(int argc, const char **argv, const char *prefix) check_symref(argv[0], quiet); break; case 2: + if (!strcmp(argv[0], "HEAD") && + prefixcmp(argv[1], "refs/heads/")) + die("Refusing to point HEAD outside of refs/heads/"); create_symref(argv[0], argv[1], msg); break; default: -- cgit v1.2.1