From 72db61d7d17a475d3cc9de1a7c871d518fcd82f0 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Mon, 24 Feb 2020 13:33:25 +0300 Subject: [PATCH] staging: kpc2000: prevent underflow in cpld_reconfigure() This function should not allow negative values of "wr_val". If negatives are allowed then capping the upper bound at 7 is meaningless. Let's make it unsigned. Fixes: 7dc7967fc39a ("staging: kpc2000: add initial set of Daktronics drivers") Signed-off-by: Dan Carpenter Cc: stable Link: https://lore.kernel.org/r/20200224103325.hrxdnaeqsthplu42@kili.mountain Signed-off-by: Greg Kroah-Hartman --- drivers/staging/kpc2000/kpc2000/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/staging/kpc2000/kpc2000/core.c b/drivers/staging/kpc2000/kpc2000/core.c index 93cf28febdf6..7b00d7069e21 100644 --- a/drivers/staging/kpc2000/kpc2000/core.c +++ b/drivers/staging/kpc2000/kpc2000/core.c @@ -110,10 +110,10 @@ static ssize_t cpld_reconfigure(struct device *dev, const char *buf, size_t count) { struct kp2000_device *pcard = dev_get_drvdata(dev); - long wr_val; + unsigned long wr_val; int rv; - rv = kstrtol(buf, 0, &wr_val); + rv = kstrtoul(buf, 0, &wr_val); if (rv < 0) return rv; if (wr_val > 7) -- 2.30.2