From cdf690e53b5f5af1ca8679b3f3e47ea198692c18 Mon Sep 17 00:00:00 2001 From: Jay Soffian Date: Wed, 25 Feb 2009 03:32:16 -0500 Subject: [PATCH] remote: make match_refs() copy src ref before assigning to peer_ref In some instances, match_refs() sets the peer_ref field of refs in the dst list such that it points to a ref in the src list. This prevents callers from freeing both the src and dst lists, as doing so would cause a double-free since free_refs() frees the peer_ref. As well, the following configuration causes two refs in the dst list to have the same peer_ref, which can also lead to a double-free: push = refs/heads/master:refs/heads/backup push = refs/heads/master:refs/heads/master Existing callers of match_heads() call it only once and then terminate, w/o ever bothering to free the src or dst lists, so this is not currently a problem. This patch modifies match_refs() to first copy any refs it plucks from the src list before assigning them as a peer_ref. This allows builtin-remote, a future caller, to free the src and dst lists. Signed-off-by: Jay Soffian Signed-off-by: Junio C Hamano --- remote.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/remote.c b/remote.c index 304e967e3..b7606acc4 100644 --- a/remote.c +++ b/remote.c @@ -936,6 +936,7 @@ static int match_explicit(struct ref *src, struct ref *dst, struct refspec *rs) { struct ref *matched_src, *matched_dst; + int copy_src; const char *dst_value = rs->dst; char *dst_guess; @@ -946,6 +947,7 @@ static int match_explicit(struct ref *src, struct ref *dst, matched_src = matched_dst = NULL; switch (count_refspec_match(rs->src, src, &matched_src)) { case 1: + copy_src = 1; break; case 0: /* The source could be in the get_sha1() format @@ -955,6 +957,7 @@ static int match_explicit(struct ref *src, struct ref *dst, matched_src = try_explicit_object_name(rs->src); if (!matched_src) return error("src refspec %s does not match any.", rs->src); + copy_src = 0; break; default: return error("src refspec %s matches more than one.", rs->src); @@ -1000,7 +1003,7 @@ static int match_explicit(struct ref *src, struct ref *dst, return error("dst ref %s receives from more than one src.", matched_dst->name); else { - matched_dst->peer_ref = matched_src; + matched_dst->peer_ref = copy_src ? copy_ref(matched_src) : matched_src; matched_dst->force = rs->force; } return 0; @@ -1108,7 +1111,7 @@ int match_refs(struct ref *src, struct ref *dst, struct ref ***dst_tail, dst_peer = make_linked_ref(dst_name, dst_tail); hashcpy(dst_peer->new_sha1, src->new_sha1); } - dst_peer->peer_ref = src; + dst_peer->peer_ref = copy_ref(src); dst_peer->force = pat->force; free_name: free(dst_name); -- 2.30.2