From owner-freebsd-current Sat May 8 11:25: 0 1999 Delivered-To: freebsd-current@freebsd.org Received: from dingo.cdrom.com (castles526.castles.com [208.214.165.90]) by hub.freebsd.org (Postfix) with ESMTP id 075A614F6A for ; Sat, 8 May 1999 11:24:58 -0700 (PDT) (envelope-from mike@dingo.cdrom.com) Received: from dingo.cdrom.com (LOCALHOST [127.0.0.1]) by dingo.cdrom.com (8.9.3/8.8.8) with ESMTP id LAA01001; Sat, 8 May 1999 11:23:36 -0700 (PDT) (envelope-from mike@dingo.cdrom.com) Message-Id: <199905081823.LAA01001@dingo.cdrom.com> X-Mailer: exmh version 2.0.2 2/24/98 To: Luigi Rizzo Cc: current@freebsd.org Subject: Re: m_get(M_WAIT, ...) _can_ return NULL ? In-reply-to: Your message of "Sat, 08 May 1999 15:32:33 +0200." <199905081332.PAA07452@labinfo.iet.unipi.it> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Sat, 08 May 1999 11:23:35 -0700 From: Mike Smith Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > Hi, > > thinking about the supposed "fragility" of FreeBSD when mbufs (or > clusters) are not properly dimensioned: i notice that > in various places of the code (and this is, i think, 4.4 heritage), > there are things like > > m = m_get(M_WAIT, ...) > m->m_len = something. > > looking at the code, it seems that m_get() _can_ return a NULL pointer > even if one specifies M_WAIT. > > Could this be a potential weakness, and in this case, how shuld we go > and fix it -- by making m_get never return if there is no memory, > or by hunting all such occurrences of the code ? I engaged in part of a sweep of this sort with Andrzej a while back, but he never committed any of the changes. I'm not quite sure why. -- \\ Sometimes you're ahead, \\ Mike Smith \\ sometimes you're behind. \\ mike@smith.net.au \\ The race is long, and in the \\ msmith@freebsd.org \\ end it's only with yourself. \\ msmith@cdrom.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message