sparse-checkout: fix OOM error with mixed patterns

Add a test to t1091-sparse-checkout-builtin.sh that would result in an infinite loop and out-of-memory error before this change. The issue relies on having non-cone-mode patterns while trying to modify the patterns in cone-mode. The fix is simple, allowing us to break from the loop when the input path does not contain a slash, as the "dir" pattern we added does not. This is only a fix to the critical out-of-memory error. A better response to such a strange state will follow in a later change. Reported-by: Calbabreaker <calbabreaker@gmail.com> Helped-by: Taylor Blau <me@ttaylorr.com> Reviewed-by: Elijah Newren <newren@gmail.com> Signed-off-by: Derrick Stolee <dstolee@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Derrick Stolee committed Dec 16, 2021 at 16:13 UTC 391c3a1020127c9dbf6995effe2f84d3443292d8
2 files changed +12 -1
builtin/sparse-checkout.c
+1 -1
index d0f5c4702b..9ccdcde983 100644 --- a/builtin/sparse-checkout.c +++ b/builtin/sparse-checkout.c @@ -483,7 +483,7 @@ static void insert_recursive_pattern(struct pattern_list *pl, struct strbuf *pat char *oldpattern = e->pattern; size_t newlen; - if (slash == e->pattern) + if (!slash || slash == e->pattern) break; newlen = slash - e->pattern;
t/t1091-sparse-checkout-builtin.sh
+11
index 3921ea8013..1f877ced0c 100755 --- a/t/t1091-sparse-checkout-builtin.sh +++ b/t/t1091-sparse-checkout-builtin.sh @@ -103,6 +103,17 @@ test_expect_success 'clone --sparse' ' check_files clone a ' +test_expect_success 'switching to cone mode with non-cone mode patterns' ' + git init bad-patterns && + ( + cd bad-patterns && + git sparse-checkout init && + git sparse-checkout add dir && + git config core.sparseCheckoutCone true && + git sparse-checkout add dir + ) +' + test_expect_success 'interaction with clone --no-checkout (unborn index)' ' git clone --no-checkout "file://$(pwd)/repo" clone_no_checkout && git -C clone_no_checkout sparse-checkout init --cone &&