[PATCH] [media] pulse8-cec: avoid uninitialized data use

From: Arnd Bergmann
Date: Mon Sep 12 2016 - 04:44:39 EST


Building with -Wmaybe-uninitialized reveals the use on an uninitialized
variable containing the physical address of the device whenever
firmware before version 2 is used:

drivers/staging/media/pulse8-cec/pulse8-cec.c: In function 'pulse8_connect':
drivers/staging/media/pulse8-cec/pulse8-cec.c:447:2: error: 'pa' may be used uninitialized in this function [-Werror=maybe-uninitialized]

This sets the address to CEC_PHYS_ADDR_INVALID in this case, so we don't
try to write back the uninitialized data to the device.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Fixes: e28a6c8b3fcc ("[media] pulse8-cec: sync configuration with adapter")
---
drivers/staging/media/pulse8-cec/pulse8-cec.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/media/pulse8-cec/pulse8-cec.c b/drivers/staging/media/pulse8-cec/pulse8-cec.c
index 1158ba9f828f..64fffc709416 100644
--- a/drivers/staging/media/pulse8-cec/pulse8-cec.c
+++ b/drivers/staging/media/pulse8-cec/pulse8-cec.c
@@ -342,8 +342,10 @@ static int pulse8_setup(struct pulse8 *pulse8, struct serio *serio,
return err;
pulse8->vers = (data[0] << 8) | data[1];
dev_info(pulse8->dev, "Firmware version %04x\n", pulse8->vers);
- if (pulse8->vers < 2)
+ if (pulse8->vers < 2) {
+ *pa = CEC_PHYS_ADDR_INVALID;
return 0;
+ }

cmd[0] = MSGCODE_GET_BUILDDATE;
err = pulse8_send_and_wait(pulse8, cmd, 1, cmd[0], 4);
--
2.9.0