If remote.origin.push was set to ":", git segfaults during a push operation, due to bad parsing logic in query_matches_negative_refspec. Per bisect, the bug was introduced in: c0192df630 (refspec: add support for negative refspecs, 2020-09-30) We found this issue when rolling out git 2.29 at Dropbox - as several folks had "push = :" in their configuration. I based my diff off the master branch, but also confirmed that it patches cleanly onto maint - if the maintainers would like to also fix the segfault on 2.29 Update since Patch series V1: * Handled matching refspec explicitly * Added testing for "+:" case * Added comment explaining how the two loops work together Update since Patch series V2 * style suggestion in remote.c * Use test_config * Add test for a case with a matching refspec + negative refspec * Fix test_config to work with --add * Updated commit message to describe what git is told to do instead of segfaulting Update since Patch series V3 * Removed commit modifying test_config * Remove segfault-related comments in test * Consolidate the three tests to two tests (1st and 3rd test overlapped in functionality) * Base the patch series on the maint branch - since the bug affects 2.29.2 Update since Patch series V4 * Squashed in Junio's patch to handle non-master named branches * Explicitly use test_unconfig Appreciate the reviews from Junio and Eric! Happy Holidays! Nipunn Koorapati (2): negative-refspec: fix segfault on : refspec negative-refspec: improve comment on query_matches_negative_refspec remote.c | 16 ++++++++-- t/t5582-fetch-negative-refspec.sh | 51 +++++++++++++++++++++++++++++++ 2 files changed, 64 insertions(+), 3 deletions(-) base-commit: 898f80736c75878acc02dc55672317fcc0e0a5a6 Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-820%2Fnipunn1313%2Fnk%2Fpush-refspec-segfault-v5 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-820/nipunn1313/nk/push-refspec-segfault-v5 Pull-Request: https://github.com/gitgitgadget/git/pull/820 Range-diff vs v4: 1: e59ff29bdef ! 1: 48c79dc3d84 negative-refspec: fix segfault on : refspec @@ t/t5582-fetch-negative-refspec.sh: test_expect_success "fetch --prune with negat ' +test_expect_success "push with matching : and negative refspec" ' -+ test_config -C two remote.one.push : && -+ # Fails to push master w/ tip behind counterpart ++ # Manually handle cleanup, since test_config is not ++ # prepared to take arbitrary options like --add ++ test_when_finished "test_unconfig -C two remote.one.push" && ++ ++ # For convenience, we use "master" to refer to the name of ++ # the branch created by default in the following. ++ # ++ # Repositories two and one have branches other than "master" ++ # but they have no overlap---"master" is the only one that ++ # is shared between them. And the master branch at two is ++ # behind the master branch at one by one commit. ++ git -C two config --add remote.one.push : && ++ ++ # A matching push tries to update master, fails due to non-ff + test_must_fail git -C two push one && + ++ # "master" may actually not be "master"---find it out. ++ current=$(git symbolic-ref HEAD) && ++ + # If master is in negative refspec, then the command will not attempt + # to push and succeed. -+ # We do not need test_config here as we are updating remote.one.push -+ # again. The teardown of the first test_config will do --unset-all -+ git -C two config --add remote.one.push ^refs/heads/master && -+ git -C two push one ++ git -C two config --add remote.one.push "^$current" && ++ ++ # With "master" excluded, this push is a no-op. Nothing gets ++ # pushed and it succeeds. ++ git -C two push -v one +' + +test_expect_success "push with matching +: and negative refspec" ' -+ test_config -C two remote.one.push +: && -+ # Fails to push master w/ tip behind counterpart ++ test_when_finished "test_unconfig -C two remote.one.push" && ++ ++ # The same set-up as above, whose side-effect was a no-op. ++ git -C two config --add remote.one.push +: && ++ ++ # The push refuses to update the "master" branch that is checked ++ # out in the "one" repository, even when it is forced with +: + test_must_fail git -C two push one && + ++ # "master" may actually not be "master"---find it out. ++ current=$(git symbolic-ref HEAD) && ++ + # If master is in negative refspec, then the command will not attempt + # to push and succeed -+ git -C two config --add remote.one.push ^refs/heads/master && -+ git -C two push one ++ git -C two config --add remote.one.push "^$current" && ++ ++ # With "master" excluded, this push is a no-op. Nothing gets ++ # pushed and it succeeds. ++ git -C two push -v one +' + test_done 2: 20575407cc0 = 2: 1f9af0e991c negative-refspec: improve comment on query_matches_negative_refspec -- gitgitgadget
