From 487af0cf6687dc48b0a960fa2f39894e2d84d77b Mon Sep 17 00:00:00 2001 From: Edward Thomson Date: Sat, 16 Dec 2023 11:19:07 +0000 Subject: [PATCH] index: correct index has_dir_name check `has_dir_name` is used to check for directory/file collisions, and attempts to determine whether the index contains a file with a directory name that is a proper subset of the new index entry that we're trying to add. To determine directory name, the function would walk the path string backwards to identify a `/`, stopping at the end of the string. However, the function assumed that the strings did not start with a `/`. If the paths contain only a single `/` at the beginning of the string, then the function would continue the loop, erroneously, when they should have stopped at the first character. Correct the order of the tests to terminate properly. Credit to Michael Rodler (@f0rki) and Amazon AWS Security. --- src/libgit2/index.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/src/libgit2/index.c b/src/libgit2/index.c index 9d919093b..ccb38230a 100644 --- a/src/libgit2/index.c +++ b/src/libgit2/index.c @@ -1185,10 +1185,13 @@ static int has_dir_name(git_index *index, size_t len, pos; for (;;) { - if (*--slash == '/') - break; + slash--; + if (slash <= entry->path) return 0; + + if (*slash == '/') + break; } len = slash - name;