From: Derrick Stolee <dstolee@xxxxxxxxxxxxx> 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 <peff@xxxxxxxx> Signed-off-by: Derrick Stolee <dstolee@xxxxxxxxxxxxx> --- commit-reach.c | 36 +++++++++++++++++++++++++++++------- t/helper/test-reach.c | 22 +++++++++++++++++----- t/t6600-test-reach.sh | 30 ++++++++++++++++++++++++++++-- 3 files changed, 74 insertions(+), 14 deletions(-) diff --git a/commit-reach.c b/commit-reach.c index 86715c103c..e748414d04 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 eb21103998..08d2ea68e8 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 d139a00d1d..ae94b27f70 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 -- gitgitgadget