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

From	Arnd Bergmann <arnd@arndb.de>
Newsgroups	linux.kernel
Subject	[PATCH] [media] pulse8-cec: avoid uninitialized data use
Date	2016-09-12 10:50 +0200
Message-ID	<sgv6a-So-7@gated-at.bofh.it> (permalink)
Organization	linux.* mail to news gateway

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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@arndb.de>
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

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[PATCH] [media] pulse8-cec: avoid uninitialized data use Arnd Bergmann <arnd@arndb.de> - 2016-09-12 10:50 +0200

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