[PATCH 3/3] unpack-trees: detect mismatching number of cache-tree/index entries
From: Patrick Steinhardt <hidden>
Date: 2024-09-17 07:13:15
Subsystem:
the rest · Maintainer:
Linus Torvalds
Same as the preceding commit, we unconditionally dereference the index's cache entries depending on the number of cache-tree entries, which can lead to a segfault when the cache-tree is corrupted. Fix this bug. This also makes t4058 pass with the leak sanitizer enabled. Signed-off-by: Patrick Steinhardt <redacted> --- t/t4058-diff-duplicates.sh | 7 +++++-- unpack-trees.c | 2 ++ 2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/t/t4058-diff-duplicates.sh b/t/t4058-diff-duplicates.sh
index 3f602adb055..18e5ac88c31 100755
--- a/t/t4058-diff-duplicates.sh
+++ b/t/t4058-diff-duplicates.sh@@ -10,6 +10,8 @@ # that the diff output isn't wildly unreasonable. test_description='test tree diff when trees have duplicate entries' + +TEST_PASSES_SANITIZE_LEAK=true . ./test-lib.sh # make_tree_entry <mode> <mode> <sha1>
@@ -143,11 +145,12 @@ test_expect_success 'reset --hard does not segfault' ' test_grep "error: corrupted cache-tree has entries not present in index" err ' -test_expect_failure 'git diff HEAD does not segfault' ' +test_expect_success 'git diff HEAD does not segfault' ' git checkout base && GIT_TEST_CHECK_CACHE_TREE=false && git reset --hard && - test_might_fail git diff HEAD + test_must_fail git diff HEAD 2>err && + test_grep "error: corrupted cache-tree has entries not present in index" err ' test_expect_failure 'can switch to another branch when status is empty' '
diff --git a/unpack-trees.c b/unpack-trees.c
index 21cc197d471..e10a9d12091 100644
--- a/unpack-trees.c
+++ b/unpack-trees.c@@ -808,6 +808,8 @@ static int traverse_by_cache_tree(int pos, int nr_entries, int nr_names, if (!o->merge) BUG("We need cache-tree to do this optimization"); + if (nr_entries + pos > o->src_index->cache_nr) + return error(_("corrupted cache-tree has entries not present in index")); /* * Do what unpack_callback() and unpack_single_entry() normally
--
2.46.0.551.gc5ee8f2d1c.dirty