[PATCH v3 0/3] sparse-checkout: fix segfault on malformed patterns

This series fixes some issues with parsing sparse-checkout patterns when core.sparseCheckoutCone is enabled but the sparse-checkout file itself contains patterns that don't match the cone mode format.

The first patch fixes a segfault first reported in [1]. The other two patches are from an earlier submission [2] that never got picked up and I lost track of. There was another patch involving 'git sparse-checkout init --cone' that isn't necessary, especially with Elijah doing some work in that space right now.

[1] https://github.com/git-for-windows/git/issues/3498 [2] https://lore.kernel.org/git/pull.1043.git.1632160658.gitgitgadget@gmail.com

Thanks, -Stolee

Updates in v2 and v3 ====================

 * I intended to fix a typo in a patch, but accidentally sent the amend!
   commit in v2
 * v3 has the typo fix properly squashed in.
 * Added Elijah's review.

Derrick Stolee (3):
  sparse-checkout: fix segfault on malformed patterns
  sparse-checkout: fix OOM error with mixed patterns
  sparse-checkout: refuse to add to bad patterns

 builtin/sparse-checkout.c          |  5 ++++-
 dir.c                              |  5 +----
 t/t1091-sparse-checkout-builtin.sh | 31 +++++++++++++++++++++++++++++-
 3 files changed, 35 insertions(+), 6 deletions(-)

base-commit: abe6bb3905392d5eb6b01fa6e54d7e784e0522aa
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1069%2Fderrickstolee%2Fsparse-checkout%2Finput-bug-v3
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1069/derrickstolee/sparse-checkout/input-bug-v3
Pull-Request: https://github.com/gitgitgadget/git/pull/1069

Range-diff vs v2:

 1:  a0e3dd335c9 ! 1:  1744a26845f sparse-checkout: fix segfault on malformed patterns
     @@ Commit message
          there is additional logic that attempts to remove the line from the hashset
          and free the data. This leads to a segfault in the 'git sparse-checkout
          list' command because it iterates over the contents of the hashset, which is
     -    no invalid.
     +    now invalid.
      
          The fix here is to stop trying to remove from the hashset. Better to leave
          bad data in the sparse-checkout matching logic (with a warning) than to
 2:  86fbf130c03 = 2:  a2fe867222e sparse-checkout: fix OOM error with mixed patterns
 3:  5d096e380a4 = 3:  a0e5a942ae0 sparse-checkout: refuse to add to bad patterns
 4:  7bacb3760f3 < -:  ----------- amend! sparse-checkout: fix segfault on malformed patterns