[02/23] builtin/log: fix leaking branch name when creating cover letters

Commit Message

Patrick Steinhardt July 26, 2024, 12:14 p.m. UTC

When calling `make_cover_letter()` without a branch name, then we try to
derive the branch name by calling `find_branch_name()`. But while this
function returns an allocated string, we never free the result and thus
have a memory leak. Fix this.

Signed-off-by: Patrick Steinhardt <[e-mail]>
---
 builtin/log.c         | 4 +++-
 t/t3206-range-diff.sh | 1 +
 2 files changed, 4 insertions(+), 1 deletion(-)

Comments

karthik nayak July 30, 2024, 9:14 a.m. UTC | #1

Patrick Steinhardt <[e-mail]> writes:

> When calling `make_cover_letter()` without a branch name, then we try to

Nit: s/then//

> derive the branch name by calling `find_branch_name()`. But while this
> function returns an allocated string, we never free the result and thus
> have a memory leak. Fix this.

[snip]

Taylor Blau July 31, 2024, 4:23 p.m. UTC | #2

On Tue, Jul 30, 2024 at 02:14:00AM -0700, Karthik Nayak wrote:
> Patrick Steinhardt <[e-mail]> writes:
>
> > When calling `make_cover_letter()` without a branch name, then we try to
>
> Nit: s/then//

Good spotting :-).

Thanks,
Taylor

Patch

diff --git a/builtin/log.c b/builtin/log.c
index 4d4b60caa7..a73a767606 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -1434,6 +1434,7 @@  static void make_cover_letter(struct rev_info *rev, int use_separate_file,
 	int need_8bit_cte = 0;
 	struct pretty_print_context pp = {0};
 	struct commit *head = list[0];
+	char *to_free = NULL;
 
 	if (!cmit_fmt_is_mail(rev->commit_format))
 		die(_("cover letter needs email format"));
@@ -1455,7 +1456,7 @@  static void make_cover_letter(struct rev_info *rev, int use_separate_file,
 	}
 
 	if (!branch_name)
-		branch_name = find_branch_name(rev);
+		branch_name = to_free = find_branch_name(rev);
 
 	pp.fmt = CMIT_FMT_EMAIL;
 	pp.date_mode.type = DATE_RFC2822;
@@ -1466,6 +1467,7 @@  static void make_cover_letter(struct rev_info *rev, int use_separate_file,
 			   encoding, need_8bit_cte, cfg);
 	fprintf(rev->diffopt.file, "%s\n", sb.buf);
 
+	free(to_free);
 	free(pp.after_subject);
 	strbuf_release(&sb);
 
diff --git a/t/t3206-range-diff.sh b/t/t3206-range-diff.sh
index a767c3520e..973e20254b 100755
--- a/t/t3206-range-diff.sh
+++ b/t/t3206-range-diff.sh
@@ -5,6 +5,7 @@  test_description='range-diff tests'
 GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main
 export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 
+TEST_PASSES_SANITIZE_LEAK=true
 . ./test-lib.sh
 
 # Note that because of the range-diff's heuristics, test_commit does more