Ensure that our variable checking for >= 0 is signed

Last-Update: 2020-03-17
Bug-Debian: https://bugs.debian.org/954127

The type of v->n is size_t, which is an unsigned type, and we are assigning
v->n - 1 to i and looping while this is >= 0.  If v->n == 0, on some
architectures (armhf) this results in i being set to a positive value
(specifically, UINT32_MAX).

Gbp-Pq: Name ensure-signed-comparison.patch

diff --git a/mag.c b/mag.c
index acdca2982f56b2ef03f561fa79135d4714fc047c..f9364c9d56235f977e61bb95a135c6835209e0f4 100644 (file)
--- a/mag.c
+++ b/mag.c
@@ -506,7 +506,7 @@ double mag_cal_rdist(mag_t *g)
 
        for (j = 0; j < 2; ++j) {
                sum_n = sum_l = 0;
-               for (i = v->n - 1; i >= 0; --i) {
+               for (i = (int64_t)v->n - 1; i >= 0; --i) {
                        const magv_t *p = &v->a[srt[i]<<32>>32];
                        int tmp1, tmp2;
                        tmp1 = tmp2 = 0;