From owner-freebsd-bugs@FreeBSD.ORG  Tue Jan 13 03:12:35 2015
Return-Path: <owner-freebsd-bugs@FreeBSD.ORG>
Delivered-To: freebsd-bugs@FreeBSD.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))
 (No client certificate requested)
 by hub.freebsd.org (Postfix) with ESMTPS id CB328E70
 for <freebsd-bugs@FreeBSD.org>; Tue, 13 Jan 2015 03:12:35 +0000 (UTC)
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 B2D169AA
 for <freebsd-bugs@FreeBSD.org>; Tue, 13 Jan 2015 03:12:35 +0000 (UTC)
Received: from bugs.freebsd.org ([127.0.1.118])
 by kenobi.freebsd.org (8.14.9/8.14.9) with ESMTP id t0D3CZKw072775
 for <freebsd-bugs@FreeBSD.org>; Tue, 13 Jan 2015 03:12:35 GMT
 (envelope-from bugzilla-noreply@freebsd.org)
From: bugzilla-noreply@freebsd.org
To: freebsd-bugs@FreeBSD.org
Subject: [Bug 196666] write(2) maximum I/O size too small / inadequately
 documented in man page
Date: Tue, 13 Jan 2015 03:12:35 +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 Only Me
X-Bugzilla-Who: emaste@freebsd.org
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: <bug-196666-8@https.bugs.freebsd.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
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: 2.1.18-1
Precedence: list
List-Id: Bug reports <freebsd-bugs.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/freebsd-bugs>,
 <mailto:freebsd-bugs-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-bugs/>
List-Post: <mailto:freebsd-bugs@freebsd.org>
List-Help: <mailto:freebsd-bugs-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-bugs>,
 <mailto:freebsd-bugs-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 13 Jan 2015 03:12:35 -0000

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=196666

            Bug ID: 196666
           Summary: write(2) maximum I/O size too small / inadequately
                    documented in man page
           Product: Base System
           Version: 11.0-CURRENT
          Hardware: Any
                OS: Any
            Status: New
          Severity: Affects Only Me
          Priority: ---
         Component: kern
          Assignee: freebsd-bugs@FreeBSD.org
          Reporter: emaste@freebsd.org

write(2) claims at most INT_MAX bytes may be written at once, and EINVAL is
returned upon an attempt to exceed this:

     [EINVAL]           The value nbytes is greater than INT_MAX.

The limit depends on the debug.iosize_max_clamp:

joule% sysctl -d debug.iosize_max_clamp
debug.iosize_max_clamp: Clamp max i/o size to INT_MAX

in 11-CURRENT this defaults to 0 so the limit is actually SSIZE_MAX, as POSIX
wants, and the man page is correct

in 10-STABLE it defaults to 1 so the man page is correct but the limit is too
small

See also https://sourceforge.net/p/elftoolchain/tickets/478/ for the sort of
issue probably caused by this

-- 
You are receiving this mail because:
You are the assignee for the bug.