[PATCH 00/20] Various memory leak fixes
- From
Patrick Steinhardt <ps@pks.im>
- Date
- May 23, 2024, 12:25 UTC
- Message-ID
- <cover.1716465556.git.ps@pks.im>
Hi,
my mind had a couple of minutes where it was roaming, and of course it immediately searched for and chased down the next rabbit hole. The result is this patch series which fixes a bunch of leaks all over the place. There isn't really any structure to the leaks that I did fix -- it's mostly things that I stumbled over. In the end, this series makes another 56 test suites pass with leak checking enabled, 13 of which have already been passing without any changes.
While most things are unstructured, there are two topics that stand out:
- Patches 5 to 12 address a shortcoming of our config API. Both
`git_config_string()` and `git_config_pathname()` have a `const char
**` out parameter, but they do in fact transfer memory ownership to
the caller. This resulted in a bunch of memory leaks all over the
place. These patches thus refactor a bunch of code and then ultimately
switch the out parameter to become a `char *` - Patches 16 to 20 have the goal of making git-mv(1) memory leak free.
I had a very hard time understanding how it tracks memory. I think
this wasn't only me, or otherwise there wouldn't be calls to
`UNLEAK()` in there. In any case, I decided to rewrite the arrays to
use a `struct strvec`, which makes tracking and releasing of memory
a ton easier. It does come at the cost of more allocations because we may now
duplicate strings that we didn't before. But I think the tradeoff is
worth it because the number of strings we may now duplicate is
bounded by the number of command line arguments anyway.Thanks!
Patrick
Patrick Steinhardt (20):
t: mark a bunch of tests as leak-free
transport-helper: fix leaking helper name
strbuf: fix leak when `appendwholeline()` fails with EOF
checkout: clarify memory ownership in `unique_tracking_name()`
http: refactor code to clarify memory ownership
config: clarify memory ownership in `git_config_pathname()`
diff: refactor code to clarify memory ownership of prefixes
convert: refactor code to clarify ownership of
check_roundtrip_encoding
builtin/log: stop using globals for log config
builtin/log: stop using globals for format config
config: clarify memory ownership in `git_config_string()`
config: plug various memory leaks
builtin/credential: clear credential before exit
commit-reach: fix memory leak in `ahead_behind()`
submodule: fix leaking memory for submodule entries
strvec: add functions to replace and remove strings
builtin/mv: refactor `add_slash()` to always return allocated strings
builtin/mv duplicate string list memory
builtin/mv: refactor to use `struct strvec`
builtin/mv: fix leaks for submodule gitfile pathsMakefile | 1 + alias.c | 6 +- attr.c | 2 +- attr.h | 2 +- builtin/blame.c | 2 +- builtin/checkout.c | 14 +- builtin/commit.c | 4 +- builtin/config.c | 2 +- builtin/credential.c | 2 + builtin/log.c | 708 ++++++++++-------- builtin/merge.c | 4 +- builtin/mv.c | 222 +++--- builtin/rebase.c | 2 +- builtin/receive-pack.c | 6 +- builtin/repack.c | 8 +- builtin/worktree.c | 20 +- checkout.c | 4 +- checkout.h | 6 +- commit-reach.c | 4 + config.c | 52 +- config.h | 10 +- convert.c | 30 +- convert.h | 2 +- delta-islands.c | 2 +- diff.c | 20 +- environment.c | 16 +- environment.h | 14 +- fetch-pack.c | 4 +- fsck.c | 4 +- fsmonitor-settings.c | 5 +- gpg-interface.c | 6 +- http.c | 50 +- imap-send.c | 12 +- mailmap.c | 4 +- mailmap.h | 4 +- merge-ll.c | 6 +- pager.c | 2 +- pretty.c | 14 +- promisor-remote.h | 2 +- remote.c | 20 +- remote.h | 8 +- sequencer.c | 2 +- setup.c | 6 +- strbuf.c | 4 +- strvec.c | 20 + strvec.h | 13 + submodule-config.c | 2 + t/t0300-credentials.sh | 2 + t/t0411-clone-from-partial.sh | 1 + t/t0610-reftable-basics.sh | 1 + t/t0611-reftable-httpd.sh | 1 + t/t1013-read-tree-submodule.sh | 1 + t/t1306-xdg-files.sh | 1 + t/t1350-config-hooks-path.sh | 1 + t/t1400-update-ref.sh | 2 + t/t2013-checkout-submodule.sh | 1 + t/t2024-checkout-dwim.sh | 1 + t/t2060-switch.sh | 1 + t/t2405-worktree-submodule.sh | 1 + t/t3007-ls-files-recurse-submodules.sh | 1 + t/t3203-branch-output.sh | 2 + t/t3415-rebase-autosquash.sh | 1 + t/t3426-rebase-submodule.sh | 1 + t/t3512-cherry-pick-submodule.sh | 1 + t/t3513-revert-submodule.sh | 1 + t/t3600-rm.sh | 1 + t/t3906-stash-submodule.sh | 1 + t/t4001-diff-rename.sh | 4 +- t/t4041-diff-submodule-option.sh | 1 + t/t4043-diff-rename-binary.sh | 1 + t/t4059-diff-submodule-not-initialized.sh | 1 + t/t4060-diff-submodule-option-diff-format.sh | 1 + t/t4120-apply-popt.sh | 1 + t/t4137-apply-submodule.sh | 1 + t/t4153-am-resume-override-opts.sh | 1 + t/t4210-log-i18n.sh | 2 + t/t5563-simple-http-auth.sh | 1 + t/t5564-http-proxy.sh | 1 + t/t5581-http-curl-verbose.sh | 1 + t/t6006-rev-list-format.sh | 1 + t/t6041-bisect-submodule.sh | 1 + t/t6400-merge-df.sh | 1 + t/t6412-merge-large-rename.sh | 1 + t/t6426-merge-skip-unneeded-updates.sh | 1 + t/t6429-merge-sequence-rename-caching.sh | 1 + t/t6438-submodule-directory-file-conflicts.sh | 1 + t/t7001-mv.sh | 2 + t/t7005-editor.sh | 1 + t/t7006-pager.sh | 1 + t/t7102-reset.sh | 1 + t/t7112-reset-submodule.sh | 1 + t/t7417-submodule-path-url.sh | 1 + t/t7421-submodule-summary-add.sh | 1 + t/t7423-submodule-symlinks.sh | 1 + t/t9129-git-svn-i18n-commitencoding.sh | 1 - t/t9139-git-svn-non-utf8-commitencoding.sh | 1 - t/t9200-git-cvsexportcommit.sh | 1 + t/t9401-git-cvsserver-crlf.sh | 1 + t/t9600-cvsimport.sh | 1 + t/t9601-cvsimport-vendor-branch.sh | 1 + t/t9602-cvsimport-branches-tags.sh | 1 + t/t9603-cvsimport-patchsets.sh | 2 + t/t9604-cvsimport-timestamps.sh | 2 + t/unit-tests/t-strvec.c | 259 +++++++ t/unit-tests/test-lib.c | 13 + t/unit-tests/test-lib.h | 13 + transport-helper.c | 6 +- transport.c | 1 + upload-pack.c | 2 +- userdiff.h | 12 +- 110 files changed, 1141 insertions(+), 584 deletions(-) create mode 100644 t/unit-tests/t-strvec.c
-- 2.45.1.216.g4365c6fcf9.dirty