From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 7879) id 935FC3858430; Wed, 15 Feb 2023 10:21:42 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 935FC3858430 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1676456502; bh=tr3xwBzD1/kcbWqawLFk0ws3R+wlKYampCI+2CCeQeQ=; h=From:To:Subject:Date:From; b=Rs9SYCUCTi0KWvnDq271K8KUG6m4G/KMEHeYvR7hUczV8vPsSwYix8kcMUyE7cj/d hCBdQUSlzwOLsS2+LYInIwaFtNQHJ1qL98dmbEhxPRijpL9MtDuKmkOrXIdINbNz51 UcrZNHLWcwkIU0bIe86VyfZLJj553bkw3/7IE3SE= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Filip Kastl To: gcc-cvs@gcc.gnu.org, libstdc++-cvs@gcc.gnu.org Subject: [gcc(refs/users/pheeck/heads/sccp)] libstdc++: Fix unsafe use of dirent::d_name [PR107814] X-Act-Checkin: gcc X-Git-Author: Jonathan Wakely X-Git-Refname: refs/users/pheeck/heads/sccp X-Git-Oldrev: 2b2aafe7f90d4266dbcb056ed39c6b9d81339a41 X-Git-Newrev: f5b7c0ed79bb135b574d4227e6e1534ae3783a63 Message-Id: <20230215102142.935FC3858430@sourceware.org> Date: Wed, 15 Feb 2023 10:21:42 +0000 (GMT) List-Id: https://gcc.gnu.org/g:f5b7c0ed79bb135b574d4227e6e1534ae3783a63 commit f5b7c0ed79bb135b574d4227e6e1534ae3783a63 Author: Jonathan Wakely Date: Tue Nov 22 19:15:53 2022 +0000 libstdc++: Fix unsafe use of dirent::d_name [PR107814] Copy the fix for PR 104731 to the equivalent experimental::filesystem test. libstdc++-v3/ChangeLog: PR libstdc++/107814 * testsuite/experimental/filesystem/iterators/error_reporting.cc: Use a static buffer with space after it. Diff: --- .../filesystem/iterators/error_reporting.cc | 35 ++++++++++++++-------- 1 file changed, 22 insertions(+), 13 deletions(-) diff --git a/libstdc++-v3/testsuite/experimental/filesystem/iterators/error_reporting.cc b/libstdc++-v3/testsuite/experimental/filesystem/iterators/error_reporting.cc index f005b7d5293..aabed14679c 100644 --- a/libstdc++-v3/testsuite/experimental/filesystem/iterators/error_reporting.cc +++ b/libstdc++-v3/testsuite/experimental/filesystem/iterators/error_reporting.cc @@ -29,35 +29,44 @@ int choice; -struct dirent global_dirent; - extern "C" struct dirent* readdir(DIR*) { + // On some targets dirent::d_name is very small, but the OS allocates + // a trailing char array after the dirent struct. Emulate that here. + union State + { + struct dirent d; + char buf[sizeof(struct dirent) + 16] = {}; + }; + + static State state; + char* d_name = state.buf + offsetof(struct dirent, d_name); + switch (choice) { case 1: - global_dirent.d_ino = 999; + state.d.d_ino = 999; #if defined _GLIBCXX_HAVE_STRUCT_DIRENT_D_TYPE && defined DT_REG - global_dirent.d_type = DT_REG; + state.d.d_type = DT_REG; #endif - global_dirent.d_reclen = 0; - std::char_traits::copy(global_dirent.d_name, "file", 5); + state.d.d_reclen = 0; + std::char_traits::copy(d_name, "file", 5); choice = 0; - return &global_dirent; + return &state.d; case 2: - global_dirent.d_ino = 111; + state.d.d_ino = 111; #if defined _GLIBCXX_HAVE_STRUCT_DIRENT_D_TYPE && defined DT_DIR - global_dirent.d_type = DT_DIR; + state.d.d_type = DT_DIR; #endif - global_dirent.d_reclen = 60; - std::char_traits::copy(global_dirent.d_name, "subdir", 7); + state.d.d_reclen = 60; + std::char_traits::copy(d_name, "subdir", 7); choice = 1; - return &global_dirent; + return &state.d; default: errno = EIO; return nullptr; } - return &global_dirent; + return &state.d; } void