From d5a35c114ab6b4337a1c7598bf75c331d94ee092 Mon Sep 17 00:00:00 2001 From: Nguyễn Thái Ngọc Duy 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/commit.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'builtin/commit.c') diff --git a/builtin/commit.c b/builtin/commit.c index c46f2d18e1..f3a6ed2bf5 100644 --- a/builtin/commit.c +++ b/builtin/commit.c @@ -1259,7 +1259,7 @@ static void print_summary(const char *prefix, const unsigned char *sha1, struct commit *commit; struct strbuf format = STRBUF_INIT; unsigned char junk_sha1[20]; - const char *head = resolve_ref("HEAD", junk_sha1, 0, NULL); + const char *head; struct pretty_print_context pctx = {0}; struct strbuf author_ident = STRBUF_INIT; struct strbuf committer_ident = STRBUF_INIT; @@ -1304,6 +1304,7 @@ static void print_summary(const char *prefix, const unsigned char *sha1, rev.diffopt.break_opt = 0; diff_setup_done(&rev.diffopt); + head = resolve_ref("HEAD", junk_sha1, 0, NULL); printf("[%s%s ", !prefixcmp(head, "refs/heads/") ? head + 11 : -- cgit v1.2.3