From owner-freebsd-bugs@freebsd.org Fri Sep 4 14:09:25 2015 Return-Path: Delivered-To: freebsd-bugs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 875929CADBC for ; Fri, 4 Sep 2015 14:09:25 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 592DF13A3 for ; Fri, 4 Sep 2015 14:09:25 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id t84E9PCE077451 for ; Fri, 4 Sep 2015 14:09:25 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 202892] open with O_CREAT | O_DIRECTORY when path references a symlink Date: Fri, 04 Sep 2015 14:09:25 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 11.0-CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Many People X-Bugzilla-Who: freebsd@tom-ridge.com X-Bugzilla-Status: New X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-bugs@FreeBSD.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 04 Sep 2015 14:09:25 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D202892 Bug ID: 202892 Summary: open with O_CREAT | O_DIRECTORY when path references a symlink Product: Base System Version: 11.0-CURRENT Hardware: amd64 OS: Any Status: New Severity: Affects Many People Priority: --- Component: kern Assignee: freebsd-bugs@FreeBSD.org Reporter: freebsd@tom-ridge.com The following test code (thanks R Watson) tries to call open with O_CREAT | O_DIRECTORY, on a path that references a broken symlink. The symlink is removed, a file is created, and the call to open returns with an error ENOT= DIR. There are similar strange behaviours. For example, O_CREAT | O_DIRECTORY | O_EXCL on a symlink to a directory will result in the symlink being removed= , a file being created, and the call returning with an error. POSIX says "If O_= EXCL and O_CREAT are set, and path names a symbolic link, open() shall fail and = set errno to [EEXIST], regardless of the contents of the symbolic link. " ( http://pubs.opengroup.org/onlinepubs/009695399/functions/open.html ) but I'm not sure whether FreeBSD aims for compliance here. Even if FreeBSD doesn't = aim for compliance, this behaviour possibly breaks a possible POSIX invariant: calls which return with errors do not alter the underlying file system state (here, we get an error, but a symlink is removed and a new file is created). #include #include #include #include #include #include int main(int argc, char *argv[]) { int fd; /* Setup. */ if (unlink("broken") <=3D 0 && errno !=3D ENOENT) err(-1, "unlink(broken)"); if (unlink("target") <=3D 0 && errno !=3D ENOENT) err(-1, "unlink(target)"); if (symlink("target", "broken") < 0) err(-1, "symlink(target, broken)"); /* Test. */ fd =3D open("broken", O_CREAT | O_DIRECTORY, 0600); if (fd >=3D 0) errx(-1, "open(broken, O_CREAT | O_DIRECTORY) - no error"); else printf("Error on open() was %s\n", strerror(errno)); =EF=BF=BC } Thanks --=20 You are receiving this mail because: You are the assignee for the bug.=