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* [PATCH] Bluetooth: mgmt: Fix possible NULL dereference
@ 2012-07-19  9:49 Andrei Emeltchenko
  2012-07-19 10:23 ` Johan Hedberg
  0 siblings, 1 reply; 4+ messages in thread
From: Andrei Emeltchenko @ 2012-07-19  9:49 UTC (permalink / raw)
  To: linux-bluetooth

From: Andrei Emeltchenko <andrei.emeltchenko@intel.com>

hdev might be dereferenced in handler->func functions.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
---
 net/bluetooth/mgmt.c |   11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 2a0f695..48a83c9 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -2801,14 +2801,15 @@ int mgmt_control(struct sock *sk, struct msghdr *msg, size_t msglen)
 		goto done;
 	}
 
-	if (hdev)
+	if (hdev) {
 		mgmt_init_hdev(sk, hdev);
 
-	cp = buf + sizeof(*hdr);
+		cp = buf + sizeof(*hdr);
 
-	err = handler->func(sk, hdev, cp, len);
-	if (err < 0)
-		goto done;
+		err = handler->func(sk, hdev, cp, len);
+		if (err < 0)
+			goto done;
+	}
 
 	err = msglen;
 
-- 
1.7.9.5


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [PATCH] Bluetooth: mgmt: Fix possible NULL dereference
  2012-07-19  9:49 [PATCH] Bluetooth: mgmt: Fix possible NULL dereference Andrei Emeltchenko
@ 2012-07-19 10:23 ` Johan Hedberg
  2012-07-19 10:38   ` Andrei Emeltchenko
  0 siblings, 1 reply; 4+ messages in thread
From: Johan Hedberg @ 2012-07-19 10:23 UTC (permalink / raw)
  To: Andrei Emeltchenko; +Cc: linux-bluetooth

Hi Andrei,

On Thu, Jul 19, 2012, Andrei Emeltchenko wrote:
> From: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
> 
> hdev might be dereferenced in handler->func functions.
> 
> Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
> ---
>  net/bluetooth/mgmt.c |   11 ++++++-----
>  1 file changed, 6 insertions(+), 5 deletions(-)
> 
> diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
> index 2a0f695..48a83c9 100644
> --- a/net/bluetooth/mgmt.c
> +++ b/net/bluetooth/mgmt.c
> @@ -2801,14 +2801,15 @@ int mgmt_control(struct sock *sk, struct msghdr *msg, size_t msglen)
>  		goto done;
>  	}
>  
> -	if (hdev)
> +	if (hdev) {
>  		mgmt_init_hdev(sk, hdev);
>  
> -	cp = buf + sizeof(*hdr);
> +		cp = buf + sizeof(*hdr);
>  
> -	err = handler->func(sk, hdev, cp, len);
> -	if (err < 0)
> -		goto done;
> +		err = handler->func(sk, hdev, cp, len);
> +		if (err < 0)
> +			goto done;
> +	}
>  
>  	err = msglen;

Nack.

hdev is supposed to be NULL for some of the commands/handlers
(read_version, read_index_list, etc). With your change these mgmt
commands couldn't be called anymore. There's also a check for this
higher up in the mgmt_control function to ensure that hdev is not NULL
for other handlers:

        if ((hdev && opcode < MGMT_OP_READ_INFO) ||
                        (!hdev && opcode >= MGMT_OP_READ_INFO)) {
                err = cmd_status(sk, index, opcode,
                                 MGMT_STATUS_INVALID_INDEX);
                goto done;
        }

Johan

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] Bluetooth: mgmt: Fix possible NULL dereference
  2012-07-19 10:23 ` Johan Hedberg
@ 2012-07-19 10:38   ` Andrei Emeltchenko
  2012-07-19 11:15     ` Johan Hedberg
  0 siblings, 1 reply; 4+ messages in thread
From: Andrei Emeltchenko @ 2012-07-19 10:38 UTC (permalink / raw)
  To: linux-bluetooth

Hi Johan,

On Thu, Jul 19, 2012 at 01:23:06PM +0300, Johan Hedberg wrote:
> Hi Andrei,
> 
> On Thu, Jul 19, 2012, Andrei Emeltchenko wrote:
> > From: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
> > 
> > hdev might be dereferenced in handler->func functions.
> > 
> > Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
> > ---
> >  net/bluetooth/mgmt.c |   11 ++++++-----
> >  1 file changed, 6 insertions(+), 5 deletions(-)
> > 
> > diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
> > index 2a0f695..48a83c9 100644
> > --- a/net/bluetooth/mgmt.c
> > +++ b/net/bluetooth/mgmt.c
> > @@ -2801,14 +2801,15 @@ int mgmt_control(struct sock *sk, struct msghdr *msg, size_t msglen)
> >  		goto done;
> >  	}
> >  
> > -	if (hdev)
> > +	if (hdev) {
> >  		mgmt_init_hdev(sk, hdev);
> >  
> > -	cp = buf + sizeof(*hdr);
> > +		cp = buf + sizeof(*hdr);
> >  
> > -	err = handler->func(sk, hdev, cp, len);
> > -	if (err < 0)
> > -		goto done;
> > +		err = handler->func(sk, hdev, cp, len);
> > +		if (err < 0)
> > +			goto done;
> > +	}
> >  
> >  	err = msglen;
> 
> Nack.
> 
> hdev is supposed to be NULL for some of the commands/handlers
> (read_version, read_index_list, etc). With your change these mgmt
> commands couldn't be called anymore. There's also a check for this
> higher up in the mgmt_control function to ensure that hdev is not NULL
> for other handlers:

OK, though I do not like that division by command name.

> 
>         if ((hdev && opcode < MGMT_OP_READ_INFO) ||
>                         (!hdev && opcode >= MGMT_OP_READ_INFO)) {
>                 err = cmd_status(sk, index, opcode,
>                                  MGMT_STATUS_INVALID_INDEX);
>                 goto done;
>         }
> 


Best regards 
Andrei Emeltchenko 

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH] Bluetooth: mgmt: Fix possible NULL dereference
  2012-07-19 10:38   ` Andrei Emeltchenko
@ 2012-07-19 11:15     ` Johan Hedberg
  0 siblings, 0 replies; 4+ messages in thread
From: Johan Hedberg @ 2012-07-19 11:15 UTC (permalink / raw)
  To: Andrei Emeltchenko, linux-bluetooth

Hi Andrei,

On Thu, Jul 19, 2012, Andrei Emeltchenko wrote:
> On Thu, Jul 19, 2012 at 01:23:06PM +0300, Johan Hedberg wrote:
> > Hi Andrei,
> > 
> > On Thu, Jul 19, 2012, Andrei Emeltchenko wrote:
> > > From: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
> > > 
> > > hdev might be dereferenced in handler->func functions.
> > > 
> > > Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
> > > ---
> > >  net/bluetooth/mgmt.c |   11 ++++++-----
> > >  1 file changed, 6 insertions(+), 5 deletions(-)
> > > 
> > > diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
> > > index 2a0f695..48a83c9 100644
> > > --- a/net/bluetooth/mgmt.c
> > > +++ b/net/bluetooth/mgmt.c
> > > @@ -2801,14 +2801,15 @@ int mgmt_control(struct sock *sk, struct msghdr *msg, size_t msglen)
> > >  		goto done;
> > >  	}
> > >  
> > > -	if (hdev)
> > > +	if (hdev) {
> > >  		mgmt_init_hdev(sk, hdev);
> > >  
> > > -	cp = buf + sizeof(*hdr);
> > > +		cp = buf + sizeof(*hdr);
> > >  
> > > -	err = handler->func(sk, hdev, cp, len);
> > > -	if (err < 0)
> > > -		goto done;
> > > +		err = handler->func(sk, hdev, cp, len);
> > > +		if (err < 0)
> > > +			goto done;
> > > +	}
> > >  
> > >  	err = msglen;
> > 
> > Nack.
> > 
> > hdev is supposed to be NULL for some of the commands/handlers
> > (read_version, read_index_list, etc). With your change these mgmt
> > commands couldn't be called anymore. There's also a check for this
> > higher up in the mgmt_control function to ensure that hdev is not NULL
> > for other handlers:
> 
> OK, though I do not like that division by command name.

I was originally thinking of having a boolean flag for that in the
look-up table but concluded that it's a bit overkill (not to mention
that it breaks the clean formatting) since only the first few commands
are the ones that don't take a valid controller index.

Johan

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2012-07-19 11:15 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2012-07-19  9:49 [PATCH] Bluetooth: mgmt: Fix possible NULL dereference Andrei Emeltchenko
2012-07-19 10:23 ` Johan Hedberg
2012-07-19 10:38   ` Andrei Emeltchenko
2012-07-19 11:15     ` Johan Hedberg

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