GCC8 started emitting warning about using strncpy with number of bytes exactly equal destination size, which is generally unsafe, as can lead to non-zero terminated string being copied. Use IFNAMSIZ - 1 as number of bytes to ensure name is always zero-terminated. Cc: Magnus Karlsson <magnus.karlsson@xxxxxxxxx> Signed-off-by: Andrii Nakryiko <andriin@xxxxxx> --- tools/lib/bpf/xsk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c index bf15a80a37c2..9588e7f87d0b 100644 --- a/tools/lib/bpf/xsk.c +++ b/tools/lib/bpf/xsk.c @@ -327,7 +327,7 @@ static int xsk_get_max_queues(struct xsk_socket *xsk) channels.cmd = ETHTOOL_GCHANNELS; ifr.ifr_data = (void *)&channels; - strncpy(ifr.ifr_name, xsk->ifname, IFNAMSIZ); + strncpy(ifr.ifr_name, xsk->ifname, IFNAMSIZ - 1); err = ioctl(fd, SIOCETHTOOL, &ifr); if (err && errno != EOPNOTSUPP) { ret = -errno; -- 2.17.1