From 6d8684161ee9c03bed5cb69ae76dfdddb85a0003 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Fri, 13 Sep 2019 16:32:43 +0200 Subject: mingw: fix quoting of arguments We need to be careful to follow proper quoting rules. For example, if an argument contains spaces, we have to quote them. Double-quotes need to be escaped. Backslashes need to be escaped, but only if they are followed by a double-quote character. We need to be _extra_ careful to consider the case where an argument ends in a backslash _and_ needs to be quoted: in this case, we append a double-quote character, i.e. the backslash now has to be escaped! The current code, however, fails to recognize that, and therefore can turn an argument that ends in a single backslash into a quoted argument that now ends in an escaped double-quote character. This allows subsequent command-line parameters to be split and part of them being mistaken for command-line options, e.g. through a maliciously-crafted submodule URL during a recursive clone. Technically, we would not need to quote _all_ arguments which end in a backslash _unless_ the argument needs to be quoted anyway. For example, `test\` would not need to be quoted, while `test \` would need to be. To keep the code simple, however, and therefore easier to reason about and ensure its correctness, we now _always_ quote an argument that ends in a backslash. This addresses CVE-2019-1350. Signed-off-by: Johannes Schindelin --- t/t7416-submodule-dash-url.sh | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 't/t7416-submodule-dash-url.sh') diff --git a/t/t7416-submodule-dash-url.sh b/t/t7416-submodule-dash-url.sh index 459193c976..2966e93071 100755 --- a/t/t7416-submodule-dash-url.sh +++ b/t/t7416-submodule-dash-url.sh @@ -31,4 +31,18 @@ test_expect_success 'clone rejects unprotected dash' ' test_i18ngrep ignoring err ' +test_expect_success 'trailing backslash is handled correctly' ' + git init testmodule && + test_commit -C testmodule c && + git submodule add ./testmodule && + : ensure that the name ends in a double backslash && + sed -e "s|\\(submodule \"testmodule\\)\"|\\1\\\\\\\\\"|" \ + -e "s|url = .*|url = \" --should-not-be-an-option\"|" \ + <.gitmodules >.new && + mv .new .gitmodules && + git commit -am "Add testmodule" && + test_must_fail git clone --verbose --recurse-submodules . dolly 2>err && + test_i18ngrep ! "unknown option" err +' + test_done -- cgit v1.2.3