From 524c0183c999c59940ce1a8712b78e4dbd87ae60 Mon Sep 17 00:00:00 2001 From: Patrick Steinhardt Date: Wed, 12 Jun 2024 10:03:23 +0200 Subject: [PATCH] config: fix segfault when parsing "core.abbrev" without repo The "core.abbrev" config allows the user to specify the minimum length when abbreviating object hashes. Next to the values "auto" and "no", this config also accepts a concrete length that needs to be bigger or equal to the minimum length and smaller or equal to the hash algorithm's hex length. While the former condition is trivial, the latter depends on the object format used by the current repository. It is thus a variable upper boundary that may either be 40 (SHA-1) or 64 (SHA-256). This has two major downsides. First, the user that specifies this config must be aware of the object hashes that its repository use. If they want to configure the value globally, then they cannot pick any value in the range `[41, 64]` if they have any repository that uses SHA-1. If they did, Git would error out when parsing the config. Second, and more importantly, parsing "core.abbrev" crashes when outside of a Git repository because we dereference `the_hash_algo` to figure out its hex length. Starting with c8aed5e8da (repository: stop setting SHA1 as the default object hash, 2024-05-07) though, we stopped initializing `the_hash_algo` outside of Git repositories. Fix both of these issues by not making it an error anymore when the given length exceeds the hash length. Instead, leave the abbreviated length intact. `repo_find_unique_abbrev_r()` handles this just fine except for a performance penalty which we will fix in a subsequent commit. Reported-by: Kyle Lippincott Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano --- config.c | 4 ++-- t/t4202-log.sh | 12 ++++++++++++ t/t5601-clone.sh | 7 +++++++ 3 files changed, 21 insertions(+), 2 deletions(-) diff --git a/config.c b/config.c index 14461312b3..d0e9396bda 100644 --- a/config.c +++ b/config.c @@ -1456,10 +1456,10 @@ static int git_default_core_config(const char *var, const char *value, if (!strcasecmp(value, "auto")) default_abbrev = -1; else if (!git_parse_maybe_bool_text(value)) - default_abbrev = the_hash_algo->hexsz; + default_abbrev = GIT_MAX_HEXSZ; else { int abbrev = git_config_int(var, value, ctx->kvi); - if (abbrev < minimum_abbrev || abbrev > the_hash_algo->hexsz) + if (abbrev < minimum_abbrev) return error(_("abbrev length out of range: %d"), abbrev); default_abbrev = abbrev; } diff --git a/t/t4202-log.sh b/t/t4202-log.sh index 86c695eb0a..e97826458c 100755 --- a/t/t4202-log.sh +++ b/t/t4202-log.sh @@ -1237,6 +1237,18 @@ test_expect_success 'log.abbrevCommit configuration' ' test_cmp expect.whatchanged.full actual ' +test_expect_success '--abbrev-commit with core.abbrev=false' ' + git log --no-abbrev >expect && + git -c core.abbrev=false log --abbrev-commit >actual && + test_cmp expect actual +' + +test_expect_success '--abbrev-commit with core.abbrev=9000' ' + git log --no-abbrev >expect && + git -c core.abbrev=9000 log --abbrev-commit >actual && + test_cmp expect actual +' + test_expect_success 'show added path under "--follow -M"' ' # This tests for a regression introduced in v1.7.2-rc0~103^2~2 test_create_repo regression && diff --git a/t/t5601-clone.sh b/t/t5601-clone.sh index cc0b953f14..5d7ea147f1 100755 --- a/t/t5601-clone.sh +++ b/t/t5601-clone.sh @@ -46,6 +46,13 @@ test_expect_success 'output from clone' ' test $(grep Clon output | wc -l) = 1 ' +test_expect_success 'output from clone with core.abbrev does not crash' ' + rm -fr dst && + echo "Cloning into ${SQ}dst${SQ}..." >expect && + git -c core.abbrev=12 clone -n "file://$(pwd)/src" dst >actual 2>&1 && + test_cmp expect actual +' + test_expect_success 'clone does not keep pack' ' rm -fr dst &&