From d5a35c114ab6b4337a1c7598bf75c331d94ee092 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Nguy=E1=BB=85n=20Th=C3=A1i=20Ng=E1=BB=8Dc=20Duy?= Date: Sun, 13 Nov 2011 17:22:15 +0700 Subject: Copy resolve_ref() return value for longer use MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit resolve_ref() may return a pointer to a static buffer. Callers that use this value longer than a couple of statements should copy the value to avoid some hidden resolve_ref() call that may change the static buffer's value. The bug found by Tony Wang in builtin/merge.c demonstrates this. The first call is in cmd_merge() branch = resolve_ref("HEAD", head_sha1, 0, &flag); Then deep in lookup_commit_or_die() a few lines after, resolve_ref() may be called again and destroy "branch". lookup_commit_or_die lookup_commit_reference lookup_commit_reference_gently parse_object lookup_replace_object do_lookup_replace_object prepare_replace_object for_each_replace_ref do_for_each_ref get_loose_refs get_ref_dir get_ref_dir resolve_ref All call sites are checked and made sure that xstrdup() is called if the value should be saved. Signed-off-by: Nguyễn Thái Ngọc Duy Signed-off-by: Junio C Hamano --- builtin/notes.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'builtin/notes.c') diff --git a/builtin/notes.c b/builtin/notes.c index f8e437db01..10b8bc7ad9 100644 --- a/builtin/notes.c +++ b/builtin/notes.c @@ -804,6 +804,7 @@ static int merge_commit(struct notes_merge_options *o) struct notes_tree *t; struct commit *partial; struct pretty_print_context pretty_ctx; + int ret; /* * Read partial merge result from .git/NOTES_MERGE_PARTIAL, @@ -828,6 +829,7 @@ static int merge_commit(struct notes_merge_options *o) o->local_ref = resolve_ref("NOTES_MERGE_REF", sha1, 0, NULL); if (!o->local_ref) die("Failed to resolve NOTES_MERGE_REF"); + o->local_ref = xstrdup(o->local_ref); if (notes_merge_commit(o, t, partial, sha1)) die("Failed to finalize notes merge"); @@ -843,7 +845,9 @@ static int merge_commit(struct notes_merge_options *o) free_notes(t); strbuf_release(&msg); - return merge_abort(o); + ret = merge_abort(o); + free((char *)o->local_ref); + return ret; } static int merge(int argc, const char **argv, const char *prefix) -- cgit v1.2.1