axconfig.c, nrconfig.c, roseconfig.c: Fix GCC 11 warnings.

GCC 11's overyealously throws below warnings.  Fixed by giving GCC a hint
that the string actually is short enough to fit.

libtool: compile:  gcc -DHAVE_CONFIG_H -I. -DAX25_SYSCONFDIR=\"/usr/local/etc/ax25/\" -DAX25_LOCALSTATEDIR=\"/usr/local/var/ax25/\" -g -O2 -Wall -MT axconfig.lo -MD -MP -MF .deps/axconfig.Tpo -c axconfig.c  -fPIC -DPIC -o .libs/axconfig.o
axconfig.c: In function ‘ax25_config_load_ports’:
axconfig.c:315:25: warning: ‘strncpy’ output may be truncated copying 15 bytes from a string of length 255 [-Wstringop-truncation]
  315 |                         strncpy(ifr.ifr_name, s, IFNAMSIZ-1);
      |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[...]
libtool: compile:  gcc -DHAVE_CONFIG_H -I. -DAX25_SYSCONFDIR=\"/usr/local/etc/ax25/\" -DAX25_LOCALSTATEDIR=\"/usr/local/var/ax25/\" -g -O2 -Wall -MT nrconfig.lo -MD -MP -MF .deps/nrconfig.Tpo -c nrconfig.c  -fPIC -DPIC -o .libs/nrconfig.o
nrconfig.c: In function ‘nr_config_load_ports’:
nrconfig.c:294:25: warning: ‘strncpy’ output may be truncated copying 15 bytes from a string of length 255 [-Wstringop-truncation]
  294 |                         strncpy(ifr.ifr_name, s, IFNAMSIZ-1);
      |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[...]
libtool: compile:  gcc -DHAVE_CONFIG_H -I. -DAX25_SYSCONFDIR=\"/usr/local/etc/ax25/\" -DAX25_LOCALSTATEDIR=\"/usr/local/var/ax25/\" -g -O2 -Wall -MT rsconfig.lo -MD -MP -MF .deps/rsconfig.Tpo -c rsconfig.c  -fPIC -DPIC -o .libs/rsconfig.o
rsconfig.c: In function ‘rs_config_load_ports’:
rsconfig.c:240:25: warning: ‘strncpy’ output may be truncated copying 15 bytes from a string of length 255 [-Wstringop-truncation]
  240 |                         strncpy(ifr.ifr_name, s, IFNAMSIZ-1);
      |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/nrconfig.c b/nrconfig.c
index 003dfb2..18fb6e1 100644
--- a/nrconfig.c
+++ b/nrconfig.c
@@ -18,6 +18,8 @@
 #include <netax25/axlib.h>
 #include <netax25/nrconfig.h>
 
+#include "util.h"
+
 typedef struct _nrport
 {
 	struct _nrport *Next;
@@ -291,6 +293,8 @@ int nr_config_load_ports(void)
 			while (isspace(*s & 0xff)) ++s;
 
 			memset(&ifr, 0, sizeof(ifr));
+			if (strlen(s) >= IFNAMSIZ)
+				unreachable();
 			strncpy(ifr.ifr_name, s, IFNAMSIZ-1);
 			ifr.ifr_name[IFNAMSIZ-1] = 0;