[PATCH 03/12] builtin/submodule--helper: release unused strbuf to avoid leak
- From
andrzej@ahunt.org <andrzej@ahunt.org>
- Date
- Jun 20, 2021, 15:11 UTC
- Message-ID
- <20210620151204.19260-4-andrzej@ahunt.org>
- In-Reply-To
- <20210620151204.19260-1-andrzej@ahunt.org>
From: Andrzej Hunt <ajrhunt@google.com>
relative_url() populates sb. In the normal return path, its buffer is detached using strbuf_detach(). However the early return path does nothing with sb, which means that sb's memory is leaked - therefore we add a release to avoid this leak.
The reset is also only necessary for the normal return path, hence we move it down to after the early-return to avoid unnecessary work.
LSAN output from t0060:
Direct leak of 121 byte(s) in 1 object(s) allocated from:
#0 0x7f31246f28b0 in realloc (/usr/lib64/libasan.so.4+0xdc8b0)
#1 0x98d7d6 in xrealloc wrapper.c:126
#2 0x909a60 in strbuf_grow strbuf.c:98
#3 0x90bf00 in strbuf_vaddf strbuf.c:401
#4 0x90c321 in strbuf_addf strbuf.c:335
#5 0x5cb78d in relative_url builtin/submodule--helper.c:182
#6 0x5cbe46 in resolve_relative_url_test builtin/submodule--helper.c:248
#7 0x410dcd in run_builtin git.c:475
#8 0x410dcd in handle_builtin git.c:729
#9 0x414087 in run_argv git.c:818
#10 0x414087 in cmd_main git.c:949
#11 0x40e9ec in main common-main.c:52
#12 0x7f3123c41349 in __libc_start_main (/lib64/libc.so.6+0x24349)SUMMARY: AddressSanitizer: 121 byte(s) leaked in 1 allocation(s).
Signed-off-by: Andrzej Hunt <andrzej@ahunt.org> --- builtin/submodule--helper.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c index ae6174ab05..4015d114b3 100644 --- a/builtin/submodule--helper.c +++ b/builtin/submodule--helper.c @@ -188,11 +188,13 @@ static char *relative_url(const char *remote_url, out = xstrdup(sb.buf + 2); else out = xstrdup(sb.buf); - strbuf_reset(&sb); - if (!up_path || !is_relative) + if (!up_path || !is_relative) { + strbuf_release(&sb); return out; + } + strbuf_reset(&sb); strbuf_addf(&sb, "%s%s", up_path, out); free(out); return strbuf_detach(&sb, NULL);
-- 2.26.2