From b67f6b26e354813d8cd792dcb3eb1a1b60b98a08 Mon Sep 17 00:00:00 2001 From: Derrick Stolee Date: Fri, 21 Sep 2018 08:05:26 -0700 Subject: commit-reach: properly peel tags The can_all_from_reach_with_flag() algorithm was refactored in 4fbcca4e "commit-reach: make can_all_from_reach... linear" but incorrectly assumed that all objects provided were commits. During a fetch negotiation, ok_to_give_up() in upload-pack.c may provide unpeeled tags to the 'from' array. The current code creates a segfault. Add a direct call to can_all_from_reach_with_flag() in 'test-tool reach' and add a test in t6600-test-reach.sh that demonstrates this segfault. Correct the issue by peeling tags when investigating the initial list of objects in the 'from' array. Signed-off-by: Jeff King Signed-off-by: Derrick Stolee Signed-off-by: Junio C Hamano diff --git a/commit-reach.c b/commit-reach.c index 86715c1..e748414 100644 --- a/commit-reach.c +++ b/commit-reach.c @@ -544,20 +544,42 @@ int can_all_from_reach_with_flag(struct object_array *from, { struct commit **list = NULL; int i; + int nr_commits; int result = 1; ALLOC_ARRAY(list, from->nr); + nr_commits = 0; for (i = 0; i < from->nr; i++) { - list[i] = (struct commit *)from->objects[i].item; + struct object *from_one = from->objects[i].item; - if (parse_commit(list[i]) || - list[i]->generation < min_generation) - return 0; + if (!from_one || from_one->flags & assign_flag) + continue; + + from_one = deref_tag(the_repository, from_one, + "a from object", 0); + if (!from_one || from_one->type != OBJ_COMMIT) { + /* no way to tell if this is reachable by + * looking at the ancestry chain alone, so + * leave a note to ourselves not to worry about + * this object anymore. + */ + from->objects[i].item->flags |= assign_flag; + continue; + } + + list[nr_commits] = (struct commit *)from_one; + if (parse_commit(list[nr_commits]) || + list[nr_commits]->generation < min_generation) { + result = 0; + goto cleanup; + } + + nr_commits++; } - QSORT(list, from->nr, compare_commits_by_gen); + QSORT(list, nr_commits, compare_commits_by_gen); - for (i = 0; i < from->nr; i++) { + for (i = 0; i < nr_commits; i++) { /* DFS from list[i] */ struct commit_list *stack = NULL; @@ -600,7 +622,7 @@ int can_all_from_reach_with_flag(struct object_array *from, } cleanup: - for (i = 0; i < from->nr; i++) { + for (i = 0; i < nr_commits; i++) { clear_commit_marks(list[i], RESULT); clear_commit_marks(list[i], assign_flag); } diff --git a/t/helper/test-reach.c b/t/helper/test-reach.c index eb21103..08d2ea6 100644 --- a/t/helper/test-reach.c +++ b/t/helper/test-reach.c @@ -31,6 +31,7 @@ int cmd__reach(int ac, const char **av) struct object_id oid_A, oid_B; struct commit *A, *B; struct commit_list *X, *Y; + struct object_array X_obj = OBJECT_ARRAY_INIT; struct commit **X_array; int X_nr, X_alloc; struct strbuf buf = STRBUF_INIT; @@ -49,7 +50,8 @@ int cmd__reach(int ac, const char **av) while (strbuf_getline(&buf, stdin) != EOF) { struct object_id oid; - struct object *o; + struct object *orig; + struct object *peeled; struct commit *c; if (buf.len < 3) continue; @@ -57,14 +59,14 @@ int cmd__reach(int ac, const char **av) if (get_oid_committish(buf.buf + 2, &oid)) die("failed to resolve %s", buf.buf + 2); - o = parse_object(r, &oid); - o = deref_tag_noverify(o); + orig = parse_object(r, &oid); + peeled = deref_tag_noverify(orig); - if (!o) + if (!peeled) die("failed to load commit for input %s resulting in oid %s\n", buf.buf, oid_to_hex(&oid)); - c = object_as_type(r, o, OBJ_COMMIT, 0); + c = object_as_type(r, peeled, OBJ_COMMIT, 0); if (!c) die("failed to load commit for input %s resulting in oid %s\n", @@ -85,6 +87,7 @@ int cmd__reach(int ac, const char **av) commit_list_insert(c, &X); ALLOC_GROW(X_array, X_nr + 1, X_alloc); X_array[X_nr++] = c; + add_object_array(orig, NULL, &X_obj); break; case 'Y': @@ -113,6 +116,15 @@ int cmd__reach(int ac, const char **av) print_sorted_commit_ids(list); } else if (!strcmp(av[1], "can_all_from_reach")) { printf("%s(X,Y):%d\n", av[1], can_all_from_reach(X, Y, 1)); + } else if (!strcmp(av[1], "can_all_from_reach_with_flag")) { + struct commit_list *iter = Y; + + while (iter) { + iter->item->object.flags |= 2; + iter = iter->next; + } + + printf("%s(X,_,_,0,0):%d\n", av[1], can_all_from_reach_with_flag(&X_obj, 2, 4, 0, 0)); } else if (!strcmp(av[1], "commit_contains")) { struct ref_filter filter; struct contains_cache cache; diff --git a/t/t6600-test-reach.sh b/t/t6600-test-reach.sh index d139a00..ae94b27 100755 --- a/t/t6600-test-reach.sh +++ b/t/t6600-test-reach.sh @@ -31,7 +31,8 @@ test_expect_success 'setup' ' for i in $(test_seq 1 10) do test_commit "1-$i" && - git branch -f commit-1-$i + git branch -f commit-1-$i && + git tag -a -m "1-$i" tag-1-$i commit-1-$i done && for j in $(test_seq 1 9) do @@ -39,11 +40,13 @@ test_expect_success 'setup' ' x=$(($j + 1)) && test_commit "$x-1" && git branch -f commit-$x-1 && + git tag -a -m "$x-1" tag-$x-1 commit-$x-1 && for i in $(test_seq 2 10) do git merge commit-$j-$i -m "$x-$i" && - git branch -f commit-$x-$i + git branch -f commit-$x-$i && + git tag -a -m "$x-$i" tag-$x-$i commit-$x-$i done done && git commit-graph write --reachable && @@ -205,6 +208,29 @@ test_expect_success 'can_all_from_reach:miss' ' test_three_modes can_all_from_reach ' +test_expect_success 'can_all_from_reach_with_flag: tags case' ' + cat >input <<-\EOF && + X:tag-2-10 + X:tag-3-9 + X:tag-4-8 + X:commit-5-7 + X:commit-6-6 + X:commit-7-5 + X:commit-8-4 + X:commit-9-3 + Y:tag-1-9 + Y:tag-2-8 + Y:tag-3-7 + Y:commit-4-6 + Y:commit-5-5 + Y:commit-6-4 + Y:commit-7-3 + Y:commit-8-1 + EOF + echo "can_all_from_reach_with_flag(X,_,_,0,0):1" >expect && + test_three_modes can_all_from_reach_with_flag +' + test_expect_success 'commit_contains:hit' ' cat >input <<-\EOF && A:commit-7-7 -- cgit v0.10.2-6-g49f6 From 4067a64672f9db8ca38d5a2682a7cdba7938c18b Mon Sep 17 00:00:00 2001 From: Derrick Stolee Date: Fri, 21 Sep 2018 08:05:27 -0700 Subject: commit-reach: fix memory and flag leaks The can_all_from_reach_with_flag() method uses 'assign_flag' as a value we can use to mark objects temporarily during our commit walk. The intent is that these flags are removed from all objects before returning. However, this is not the case. The 'from' array could also contain objects that are not commits, and we mark those objects with 'assign_flag'. Add a loop to the 'cleanup' section that removes these markers. Also, we forgot to free() the memory for 'list', so add that to the 'cleanup' section. Signed-off-by: Derrick Stolee Signed-off-by: Junio C Hamano diff --git a/commit-reach.c b/commit-reach.c index e748414..5a84544 100644 --- a/commit-reach.c +++ b/commit-reach.c @@ -626,6 +626,11 @@ cleanup: clear_commit_marks(list[i], RESULT); clear_commit_marks(list[i], assign_flag); } + free(list); + + for (i = 0; i < from->nr; i++) + from->objects[i].item->flags &= ~assign_flag; + return result; } -- cgit v0.10.2-6-g49f6