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From: Martin Wilck <mwilck@suse.com>
To: Bart Van Assche <bart.vanassche@sandisk.com>,
	Christophe Varoqui <christophe.varoqui@opensvc.com>
Cc: "dm-devel@redhat.com" <dm-devel@redhat.com>
Subject: Re: [PATCH 4/4] multipath: Fix a potential buffer overflow
Date: Tue, 13 Jun 2017 22:18:09 +0200	[thread overview]
Message-ID: <1497385089.4654.54.camel@suse.com> (raw)
In-Reply-To: <5549db47-506b-f564-19ff-8d9dd1c36177@sandisk.com>

On Tue, 2017-06-13 at 12:53 -0700, Bart Van Assche wrote:
> On 06/13/17 12:29, Martin Wilck wrote:
> > how about this simpler patch, as prflag is actually a boolean?
> > 
> > diff --git a/multipathd/cli_handlers.c b/multipathd/cli_handlers.c
> > index 04c73866..c31ebd34 100644
> > --- a/multipathd/cli_handlers.c
> > +++ b/multipathd/cli_handlers.c
> > @@ -1337,7 +1337,7 @@ cli_getprstatus (void * v, char ** reply, int
> > * len, void * data)
> >         memset(*reply,0,2);
> >  
> >  
> > -       sprintf(*reply,"%d",mpp->prflag);
> > +       sprintf(*reply, "%d", !!mpp->prflag);
> >         (*reply)[1]='\0';
> 
> Hello Martin,
> 
> Every sprintf() call requires careful analysis to see whether or not
> it
> triggers a buffer overflow. I really would like to get rid of that
> sprintf() call.

Then we could write

	snprintf(*reply, 2, "%d", !!mpp->prflag);
  
without needing _GNU_SOURCE.

Martin

-- 
Dr. Martin Wilck <mwilck@suse.com>, Tel. +49 (0)911 74053 2107
SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton
HRB 21284 (AG Nürnberg)

--
dm-devel mailing list
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https://www.redhat.com/mailman/listinfo/dm-devel

  reply	other threads:[~2017-06-13 20:18 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-06-13 16:33 [PATCH 0/4] Four multipath-tools patches Bart Van Assche
2017-06-13 16:33 ` [PATCH 1/4] kpartx: Improve portability of set_loop() Bart Van Assche
2017-06-13 19:33   ` Martin Wilck
2017-06-13 16:33 ` [PATCH 2/4] libmultipath: Simplify assemble_map() Bart Van Assche
2017-06-13 19:32   ` Martin Wilck
2017-06-13 16:33 ` [PATCH 3/4] libmultipath/datacore: Remove dead code Bart Van Assche
2017-06-13 19:31   ` Martin Wilck
2017-06-13 16:33 ` [PATCH 4/4] multipath: Fix a potential buffer overflow Bart Van Assche
2017-06-13 19:28   ` Martin Wilck
2017-06-13 19:53     ` Bart Van Assche
2017-06-13 20:18       ` Martin Wilck [this message]
2017-06-13 20:21         ` Bart Van Assche
2017-06-13 20:35           ` Martin Wilck
2017-06-21 10:16 ` [PATCH 0/4] Four multipath-tools patches Christophe Varoqui

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