[patch] [media] av7110: wrong limiter in av7110_start_feed()

[patch] [media] av7110: wrong limiter in av7110_start_feed()

[Dan Carpenter]

Smatch complains that the wrong limiter is used here:
drivers/media/dvb/ttpci/av7110.c +906 dvb_feed_start_pid(12)
	error: buffer overflow 'npids' 5 <= 19

Here is the problem code:
   905          i = dvbdmxfeed->pes_type;
   906          npids[i] = (pid[i]&0x8000) ? 0 : pid[i];

"npids" is a 5 element array declared on the stack.  If
dvbdmxfeed->pes_type is more than 4 we probably put a (u16)0 past
the end of the array.

If dvbdmxfeed->pes_type is over 4 the rest of the function doesn't
do anything.  dvbdmxfeed->pes_type is capped at less than
DMX_TS_PES_OTHER (20) in the caller function, but I changed it to
less than or equal to DMX_TS_PES_PCR (4).

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/drivers/media/dvb/ttpci/av7110.c b/drivers/media/dvb/ttpci/av7110.c
index 3d20719..abf6b55 100644
--- a/drivers/media/dvb/ttpci/av7110.c
+++ b/drivers/media/dvb/ttpci/av7110.c
@@ -991,7 +991,7 @@ static int av7110_start_feed(struct dvb_demux_feed *feed)
 
 	if (feed->type = DMX_TYPE_TS) {
 		if ((feed->ts_type & TS_DECODER) &&
-		    (feed->pes_type < DMX_TS_PES_OTHER)) {
+		    (feed->pes_type <= DMX_TS_PES_PCR)) {
 			switch (demux->dmx.frontend->source) {
 			case DMX_MEMORY_FE:
 				if (feed->ts_type & TS_DECODER)

Re: [patch] [media] av7110: wrong limiter in av7110_start_feed()

[Oliver Endriss]

On Tuesday 18 October 2011 08:12:09 Dan Carpenter wrote:
> Smatch complains that the wrong limiter is used here:
> drivers/media/dvb/ttpci/av7110.c +906 dvb_feed_start_pid(12)
> 	error: buffer overflow 'npids' 5 <= 19
> 
> Here is the problem code:
>    905          i = dvbdmxfeed->pes_type;
>    906          npids[i] = (pid[i]&0x8000) ? 0 : pid[i];
> 
> "npids" is a 5 element array declared on the stack.  If
> dvbdmxfeed->pes_type is more than 4 we probably put a (u16)0 past
> the end of the array.
> 
> If dvbdmxfeed->pes_type is over 4 the rest of the function doesn't
> do anything.  dvbdmxfeed->pes_type is capped at less than
> DMX_TS_PES_OTHER (20) in the caller function, but I changed it to
> less than or equal to DMX_TS_PES_PCR (4).
> 
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> 
> diff --git a/drivers/media/dvb/ttpci/av7110.c b/drivers/media/dvb/ttpci/av7110.c
> index 3d20719..abf6b55 100644
> --- a/drivers/media/dvb/ttpci/av7110.c
> +++ b/drivers/media/dvb/ttpci/av7110.c
> @@ -991,7 +991,7 @@ static int av7110_start_feed(struct dvb_demux_feed *feed)
>  
>  	if (feed->type = DMX_TYPE_TS) {
>  		if ((feed->ts_type & TS_DECODER) &&
> -		    (feed->pes_type < DMX_TS_PES_OTHER)) {
> +		    (feed->pes_type <= DMX_TS_PES_PCR)) {
>  			switch (demux->dmx.frontend->source) {
>  			case DMX_MEMORY_FE:
>  				if (feed->ts_type & TS_DECODER)
> --
> To unsubscribe from this list: send the line "unsubscribe linux-media" in
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> 

Acked-by: Oliver Endriss <o.endriss@gmx.de>

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Full-TS Mod: http://www.escape-edv.de/endriss/dvb-full-ts-mod/
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