kill: check errno after strto..()

Addresses: https://github.com/karelzak/util-linux/issues/1356
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/misc-utils/kill.c b/misc-utils/kill.c
index 9cfb03cb91a9e3d550c493ea0363a3922eba17df..c70c385070af2cd75cad78fd1e0f14c4deb62fcb 100644 (file)
--- a/misc-utils/kill.c
+++ b/misc-utils/kill.c
@@ -176,10 +176,11 @@ static int arg_to_signum(char *arg, int maskbit)
        char *ep;
 
        if (isdigit(*arg)) {
+               errno = 0;
                numsig = strtol(arg, &ep, 10);
                if (NSIG <= numsig && maskbit && (numsig & 128) != 0)
                        numsig -= 128;
-               if (*ep != 0 || numsig < 0 || NSIG <= numsig)
+               if (errno || *ep != 0 || numsig < 0 || NSIG <= numsig)
                        return -1;
                return numsig;
        }