[PATCH bpf] libbpf: fix another GCC8 warning for strncpy

[PATCH bpf] libbpf: fix another GCC8 warning for strncpy

[Andrii Nakryiko]

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>
---
 tools/lib/bpf/xsk.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c
index b33740221b7e..5007b5d4fd2c 100644
--- a/tools/lib/bpf/xsk.c
+++ b/tools/lib/bpf/xsk.c
@@ -517,7 +517,8 @@ 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)
-- 
2.17.1

Re: [PATCH bpf] libbpf: fix another GCC8 warning for strncpy

[Magnus Karlsson]

On Tue, Jul 16, 2019 at 5:59 AM Andrii Nakryiko <andriin@fb.com> wrote:
>
> Similar issue was fixed in cdfc7f888c2a ("libbpf: fix GCC8 warning for
> strncpy") already. This one was missed. Fixing now.

Thanks Andrii.

Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>

> Cc: Magnus Karlsson <magnus.karlsson@intel.com>
> Signed-off-by: Andrii Nakryiko <andriin@fb.com>
> ---
>  tools/lib/bpf/xsk.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c
> index b33740221b7e..5007b5d4fd2c 100644
> --- a/tools/lib/bpf/xsk.c
> +++ b/tools/lib/bpf/xsk.c
> @@ -517,7 +517,8 @@ 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)
> --
> 2.17.1
>

Re: [PATCH bpf] libbpf: fix another GCC8 warning for strncpy

[Alexei Starovoitov]

On Tue, Jul 16, 2019 at 10:31 AM Magnus Karlsson
<magnus.karlsson@gmail.com> wrote:
>
> On Tue, Jul 16, 2019 at 5:59 AM Andrii Nakryiko <andriin@fb.com> wrote:
> >
> > Similar issue was fixed in cdfc7f888c2a ("libbpf: fix GCC8 warning for
> > strncpy") already. This one was missed. Fixing now.
>
> Thanks Andrii.
>
> Acked-by: Magnus Karlsson <magnus.karlsson@intel.com>

Applied. Thanks