diff mbox

[3.8,07/67,media] mxl111sf: Fix unintentional garbage stack read

Message ID 1393872955-28810-8-git-send-email-kamal@canonical.com
State New
Headers show

Commit Message

Kamal Mostafa March 3, 2014, 6:54 p.m. UTC 
3.8.13.19 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dave Jones <davej@fedoraproject.org>

commit 866e8d8a9dc1ebb4f9e67197e264ac2df81f7d4b upstream.

mxl111sf_read_reg takes an address of a variable to write to as an argument.
drivers/media/usb/dvb-usb-v2/mxl111sf-gpio.c:mxl111sf_config_pin_mux_modes
passes several uninitialized stack variables to this routine, expecting
them to be filled in.  In the event that something unexpected happens when
reading from the chip, we end up doing a pr_debug of the value passed in,
revealing whatever garbage happened to be on the stack.

Change the pr_debug to match what happens in the 'success' case, where we
assign buf[1] to *data.

Spotted with Coverity (Bugs 731910 through 731917)

Signed-off-by: Dave Jones <davej@fedoraproject.org>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
[ kamal: backport to 3.8 (context) ]
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
 drivers/media/usb/dvb-usb-v2/mxl111sf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox

Patch

diff --git a/drivers/media/usb/dvb-usb-v2/mxl111sf.c b/drivers/media/usb/dvb-usb-v2/mxl111sf.c
index efdcb15..a26cd01 100644
--- a/drivers/media/usb/dvb-usb-v2/mxl111sf.c
+++ b/drivers/media/usb/dvb-usb-v2/mxl111sf.c
@@ -103,7 +103,7 @@  int mxl111sf_read_reg(struct mxl111sf_state *state, u8 addr, u8 *data)
 		ret = -EINVAL;
 	}
 
-	deb_reg("R: (0x%02x, 0x%02x)\n", addr, *data);
+	deb_reg("R: (0x%02x, 0x%02x)\n", addr, buf[1]);
 fail:
 	return ret;
 }