Prevent terminal symlink traversal via recursive grep

2026-08-23 19:48:40 +02:00
parent 91d36a98e3
commit 2f4bff550e
2 changed files with 5 additions and 1 deletions
@@ -256,7 +256,9 @@ def validate_arguments(program: str, arguments: list[str], cwd: Path) -> list[st
        return ["-n", args[1], *[path_argument(value, cwd) for value in args[2:]]]

    if program == "grep":
-        allowed = {"-c", "-E", "-F", "-i", "-l", "-n", "-r", "-R"}
+        # GNU grep -R follows symlinks. Only -r is permitted because it skips
+        # directory symlinks and therefore preserves the visible-root boundary.
+        allowed = {"-c", "-E", "-F", "-i", "-l", "-n", "-r"}
        result = []
        index = 0
        while index < len(args) and args[index].startswith("-"):