Re: [PATCH] check_aliased_update: strcpy() instead of strcat() to copy

da3efdb (receive-pack: detect aliased updates which can occur with
symrefs, 2010-04-19) introduced two strcat() into uninitialized
strings.  The intent was clearly make a copy of the static buffer used
by find_unique_abbrev(), so use strcpy() instead.

Signed-off-by: Thomas Rast <redacted>
Reported-by: Ævar Arnfjörð Bjarmason <redacted>
---

quoted

Actually I think my test failure is related to da3efdb17b, see the
"[PATCH v2 2/2] receive-pack: detect aliased updates which can occur
with symrefs" thread.

Indeed, there's another bug in this one.  (And valgrind catches it
too...  if only I had the patience to let it churn through t5516!)

Unlike the other bug, this one is already in master.

 builtin/receive-pack.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index bb34757..7e4129d 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c

@@ -515,9 +515,9 @@ static void check_aliased_update(struct command *cmd, struct string_list *list)

       dst_cmd->skip_update = 1;

       strcpy(cmd_oldh, find_unique_abbrev(cmd->old_sha1, DEFAULT_ABBREV));
-       strcat(cmd_newh, find_unique_abbrev(cmd->new_sha1, DEFAULT_ABBREV));
+       strcpy(cmd_newh, find_unique_abbrev(cmd->new_sha1, DEFAULT_ABBREV));
       strcpy(dst_oldh, find_unique_abbrev(dst_cmd->old_sha1, DEFAULT_ABBREV));
-       strcat(dst_newh, find_unique_abbrev(dst_cmd->new_sha1, DEFAULT_ABBREV));
+       strcpy(dst_newh, find_unique_abbrev(dst_cmd->new_sha1, DEFAULT_ABBREV));
       rp_error("refusing inconsistent update between symref '%s' (%s..%s) and"
                " its target '%s' (%s..%s)",
                cmd->ref_name, cmd_oldh, cmd_newh,