From: Matti Vaittinen <mazziesaccount@gmail.com>
Date: Thu, 13 Oct 2022 12:04:04 +0000 (+0300)
Subject: tools: iio: iio_utils: fix digit calculation
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=569709540e1218a7cef561b9b1082d1507a92d4a;p=linux.git

tools: iio: iio_utils: fix digit calculation

commit 72b2aa38191bcba28389b0e20bf6b4f15017ff2b upstream.

The iio_utils uses a digit calculation in order to know length of the
file name containing a buffer number. The digit calculation does not
work for number 0.

This leads to allocation of one character too small buffer for the
file-name when file name contains value '0'. (Eg. buffer0).

Fix digit calculation by returning one digit to be present for number
'0'.

Fixes: 096f9b862e60 ("tools:iio:iio_utils: implement digit calculation")
Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Link: https://lore.kernel.org/r/Y0f+tKCz+ZAIoroQ@dc75zzyyyyyyyyyyyyycy-3.rev.dnainternet.fi
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/tools/iio/iio_utils.c b/tools/iio/iio_utils.c
index aadee6d34c74c..8d35893b2fa85 100644
--- a/tools/iio/iio_utils.c
+++ b/tools/iio/iio_utils.c
@@ -547,6 +547,10 @@ static int calc_digits(int num)
 {
 	int count = 0;
 
+	/* It takes a digit to represent zero */
+	if (!num)
+		return 1;
+
 	while (num != 0) {
 		num /= 10;
 		count++;