From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2210) id 9D0443938C08; Mon, 1 Mar 2021 14:02:11 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 9D0443938C08 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Ken Brown To: cygwin-cvs@sourceware.org Subject: [newlib-cygwin] Cygwin: fix linkat(2) on sockets that are not socket files X-Act-Checkin: newlib-cygwin X-Git-Author: Ken Brown X-Git-Refname: refs/heads/master X-Git-Oldrev: 012427c96eccd195b60cd61f3817f550f6563275 X-Git-Newrev: 425203384a6c3e19af782c86570740464423eb4d Message-Id: <20210301140211.9D0443938C08@sourceware.org> Date: Mon, 1 Mar 2021 14:02:11 +0000 (GMT) X-BeenThere: cygwin-cvs@cygwin.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Cygwin core component git logs List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 01 Mar 2021 14:02:11 -0000 https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=425203384a6c3e19af782c86570740464423eb4d commit 425203384a6c3e19af782c86570740464423eb4d Author: Ken Brown Date: Wed Feb 24 10:43:15 2021 -0500 Cygwin: fix linkat(2) on sockets that are not socket files If linkat(2) is called with AT_EMPTY_PATH on an AF_LOCAL or AF_UNIX socket that is not a socket file, the current code calls fhandler_disk_file::link in most cases. The latter expects to be operating on a disk file and uses the socket's io_handle, which is not a file handle. Fix this by calling fhandler_disk_file::link only if the fhandler_socket object is a file (determined by testing dev().isfs()). Also fix the case of a socket file opened with O_PATH by setting the fhandler_disk_file's io_handle. Diff: --- winsup/cygwin/fhandler_socket_local.cc | 7 ++++++- winsup/cygwin/fhandler_socket_unix.cc | 9 ++++++--- 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/winsup/cygwin/fhandler_socket_local.cc b/winsup/cygwin/fhandler_socket_local.cc index 22586c0dd..ad7dd0a98 100644 --- a/winsup/cygwin/fhandler_socket_local.cc +++ b/winsup/cygwin/fhandler_socket_local.cc @@ -750,9 +750,14 @@ fhandler_socket_local::facl (int cmd, int nentries, aclent_t *aclbufp) int fhandler_socket_local::link (const char *newpath) { - if (get_sun_path () && get_sun_path ()[0] == '\0') + if (!dev ().isfs ()) + /* linkat w/ AT_EMPTY_PATH called on a socket not opened w/ O_PATH. */ return fhandler_socket_wsock::link (newpath); + /* link on a socket file or linkat w/ AT_EMPTY_PATH called on a + socket opened w/ O_PATH. */ fhandler_disk_file fh (pc); + if (get_flags () & O_PATH) + fh.set_handle (get_handle ()); return fh.link (newpath); } diff --git a/winsup/cygwin/fhandler_socket_unix.cc b/winsup/cygwin/fhandler_socket_unix.cc index fae07367d..252bcd9a9 100644 --- a/winsup/cygwin/fhandler_socket_unix.cc +++ b/winsup/cygwin/fhandler_socket_unix.cc @@ -2421,11 +2421,14 @@ fhandler_socket_unix::facl (int cmd, int nentries, aclent_t *aclbufp) int fhandler_socket_unix::link (const char *newpath) { - if (sun_path () - && (sun_path ()->un_len <= (socklen_t) sizeof (sa_family_t) - || sun_path ()->un.sun_path[0] == '\0')) + if (!dev ().isfs ()) + /* linkat w/ AT_EMPTY_PATH called on a socket not opened w/ O_PATH. */ return fhandler_socket::link (newpath); + /* link on a socket file or linkat w/ AT_EMPTY_PATH called on a + socket opened w/ O_PATH. */ fhandler_disk_file fh (pc); + if (get_flags () & O_PATH) + fh.set_handle (get_handle ()); return fh.link (newpath); }