[PATCH RESEND 09/14] [media] ddbridge: fix possible buffer overflow in ddb_ports_init()

Daniel Scheller
2017-07-23T18:16:45Z

Report from smatch:

drivers/media/pci/ddbridge/ddbridge-core.c:2659 ddb_ports_init() error: buffer overflow 'dev->port' 32 <= u32max

Fix by making sure "p" is greater than zero before checking for
"dev->port[].type == DDB_CI_EXTERNAL_XO2".

Cc: Ralph Metzler <rjkm@metzlerbros.de>
Signed-off-by: Daniel Scheller <d.scheller@gmx.net>
Tested-by: Richard Scobie <r.scobie@clear.net.nz>
Tested-by: Jasmin Jessich <jasmin@anw.at>
Tested-by: Dietmar Spingler <d_spingler@freenet.de>
Tested-by: Manfred Knick <Manfred.Knick@t-online.de>
---
drivers/media/pci/ddbridge/ddbridge-core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/pci/ddbridge/ddbridge-core.c b/drivers/media/pci/ddbridge/ddbridge-core.c
index 1e5c420e4717..5f8f77c74339 100644
--- a/drivers/media/pci/ddbridge/ddbridge-core.c
+++ b/drivers/media/pci/ddbridge/ddbridge-core.c
@@ -2550,7 +2550,7 @@ void ddb_ports_init(struct ddb *dev)
port->dvb[0].adap = &dev->adap[2 * p];
port->dvb[1].adap = &dev->adap[2 * p + 1];

- if ((port->class == DDB_PORT_NONE) && i &&
+ if ((port->class == DDB_PORT_NONE) && i && p > 0 &&
dev->port[p - 1].type == DDB_CI_EXTERNAL_XO2) {
port->class = DDB_PORT_CI;
port->type = DDB_CI_EXTERNAL_XO2_B;
--
2.13.0