libbpf: fix another GCC8 warning for strncpy

[ Upstream commit 763ff0e7d9c72e7094b31e7fb84a859be9325635 ]

Similar issue was fixed in cdfc7f888c2a ("libbpf: fix GCC8 warning for
strncpy") already. This one was missed. Fixing now.

Cc: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c
index 1fe0e1eec7383bba9476dbbd3d9fb6ad266d7495..4ecd33ff46ecf9882efc7ea2d0396f7f639ee3a8 100644 (file)
--- a/tools/lib/bpf/xsk.c
+++ b/tools/lib/bpf/xsk.c
@@ -560,7 +560,8 @@ int xsk_socket__create(struct xsk_socket **xsk_ptr, const char *ifname,
                err = -errno;
                goto out_socket;
        }
-       strncpy(xsk->ifname, ifname, IFNAMSIZ);
+       strncpy(xsk->ifname, ifname, IFNAMSIZ - 1);
+       xsk->ifname[IFNAMSIZ - 1] = '\0';
 
        err = xsk_set_xdp_socket_config(&xsk->config, usr_config);
        if (err)