strbuf_attach: fix call sites to pass correct alloc

strbuf_attach(sb, buf, len, alloc) requires alloc > len (the buffer
must have at least len+1 bytes to hold the NUL). Several call sites
passed alloc == len, relying on strbuf_grow(sb, 0) inside strbuf_attach
to reallocate. Fix these in mailinfo, am, refs/files-backend,
fast-import, and trailer by passing len+1 when the buffer is a
NUL-terminated string (or from strbuf_detach).

Signed-off-by: Vaidas Pilkauskas <vaidas.pilkauskas@shopify.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/trailer.c b/trailer.c
index 911a81ed99..3afe368db0 100644
--- a/trailer.c
+++ b/trailer.c
@@ -1009,7 +1009,7 @@ static struct trailer_block *trailer_block_get(const struct process_trailer_opti
 	for (ptr = trailer_lines; *ptr; ptr++) {
 		if (last && isspace((*ptr)->buf[0])) {
 			struct strbuf sb = STRBUF_INIT;
-			strbuf_attach(&sb, *last, strlen(*last), strlen(*last));
+			strbuf_attach(&sb, *last, strlen(*last), strlen(*last) + 1);
 			strbuf_addbuf(&sb, *ptr);
 			*last = strbuf_detach(&sb, NULL);
 			continue;