lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Mon, 04 Mar 2019 16:31:40 -0600
From:   Tom Zanussi <tom.zanussi@...ux.intel.com>
To:     Steven Rostedt <rostedt@...dmis.org>,
        Tom Zanussi <zanussi@...nel.org>
Cc:     linux-kernel@...r.kernel.org, linux-rt-users@...r.kernel.org,
        Namhyung Kim <namhyung@...nel.org>
Subject: Re: [PATCH 2/2] tracing: Use strncpy instead of memcpy for string
 keys in hist triggers

Hi Steve,

On Mon, 2019-03-04 at 16:22 -0600, Tom Zanussi wrote:
> Hi Steve,
> 
> On Mon, 2019-03-04 at 16:56 -0500, Steven Rostedt wrote:
> > On Mon, 4 Mar 2019 16:50:00 -0500
> > Steven Rostedt <rostedt@...dmis.org> wrote:
> > 
> > > > +++ b/kernel/trace/trace_events_hist.c
> > > > @@ -4695,9 +4695,10 @@ static inline void add_to_key(char
> > > > *compound_key, void *key,
> > > >  		/* ensure NULL-termination */
> > > >  		if (size > key_field->size - 1)
> > > >  			size = key_field->size - 1;
> > > > -	}
> > > >  
> > > > -	memcpy(compound_key + key_field->offset, key, size);
> > > > +		strncpy(compound_key + key_field->offset, (char
> > > > *)key,
> > > > size);
> > > > +	} else
> > > > +		memcpy(compound_key + key_field->offset, key,
> > > > size);
> > > >  }
> > > >    
> > > 
> > > Shouldn't we use strncpy() in save_comm() too. Feels safer.
> > 
> > Note, if that is changed, it can be another patch. This one is fine
> > as
> > is. I just was looking at other use cases of memcpy() in that file.
> > 
> 
> Hmm, I don't think it's really necessary - it's not used in a key so
> don't care about anything after the null, and TASK_COMM_LEN is used
> in
> the memcpy.

Never mind, yeah, it would make sense to do this, will create another
patch...

Tom


> 
> Tom
> 
> > -- Steve

Powered by blists - more mailing lists