@matheusbsbs / matheus-bagliano / commits / 23424ea759

t/t5318: introduce failing 'git commit-graph write' tests

When invoking 'git commit-graph' in a corrupt repository, one can cause a segfault when ancestral commits are corrupt in one way or another. This is due to two function calls in the 'commit-graph.c' code that may return NULL, but are not checked for NULL-ness before dereferencing. Before fixing the bug, introduce two failing tests that demonstrate the problem. The first test corrupts an ancestral commit's parent to point to a non-existent object. The second test instead corrupts an ancestral tree by removing the 'tree' information entirely from the commit. Both of these cases cause segfaults, each at different lines. Signed-off-by: Taylor Blau <me@ttaylorr.com> Acked-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Taylor Blau committed Sep 5, 2019 at 18:04 UTC 23424ea7597fa17b96c82001b281a5d21f5b4874

1 file changed +43

t/t5318-commit-graph.sh

+43

@@ -585,4 +585,47 @@ test_expect_success 'get_commit_tree_in_graph works for non-the_repository' '

585 test_cmp expect actual

586 '

587

588 +test_expect_failure 'corrupt commit-graph write (broken parent)' '

589 + rm -rf repo &&

590 + git init repo &&

591 + (

592 + cd repo &&

593 + empty="$(git mktree </dev/null)" &&

594 + cat >broken <<-EOF &&

595 + tree $empty

596 + parent 0000000000000000000000000000000000000000

597 + author whatever <whatever@example.com> 1234 -0000

598 + committer whatever <whatever@example.com> 1234 -0000

599 +

600 + broken commit

601 + EOF

602 + broken="$(git hash-object -w -t commit --literally broken)" &&

603 + git commit-tree -p "$broken" -m "good commit" "$empty" >good &&

604 + test_must_fail git commit-graph write --stdin-commits \

605 + <good 2>test_err &&

606 + test_i18ngrep "unable to parse commit" test_err

607 + )

608 +'

609 +

610 +test_expect_failure 'corrupt commit-graph write (missing tree)' '

611 + rm -rf repo &&

612 + git init repo &&

613 + (

614 + cd repo &&

615 + tree="$(git mktree </dev/null)" &&

616 + cat >broken <<-EOF &&

617 + parent 0000000000000000000000000000000000000000

618 + author whatever <whatever@example.com> 1234 -0000

619 + committer whatever <whatever@example.com> 1234 -0000

620 +

621 + broken commit

622 + EOF

623 + broken="$(git hash-object -w -t commit --literally broken)" &&

624 + git commit-tree -p "$broken" -m "good" "$tree" >good &&

625 + test_must_fail git commit-graph write --stdin-commits \

626 + <good 2>test_err &&

627 + test_i18ngrep "unable to get tree for" test_err

628 + )

629 +'

630 +

631 test_done