From 5c9f7b04aadf79f783542d096dfbb8184e7c91f5 Mon Sep 17 00:00:00 2001 From: "justinstitt@google.com" Date: Tue, 18 Jul 2023 22:56:38 +0000 Subject: [PATCH] net: dsa: remove deprecated strncpy `strncpy` is deprecated for use on NUL-terminated destination strings [1]. Even call sites utilizing length-bounded destination buffers should switch over to using `strtomem` or `strtomem_pad`. In this case, however, the compiler is unable to determine the size of the `data` buffer which renders `strtomem` unusable. Due to this, `strscpy` should be used. It should be noted that most call sites already zero-initialize the destination buffer. However, I've opted to use `strscpy_pad` to maintain the same exact behavior that `strncpy` produced (zero-padded tail up to `len`). Also see [3]. [1]: www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [2]: elixir.bootlin.com/linux/v6.3/source/net/ethtool/ioctl.c#L1944 [3]: manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html Link: https://github.com/KSPP/linux/issues/90 Reviewed-by: Nick Desaulniers Reviewed-by: Kees Cook Signed-off-by: Justin Stitt Signed-off-by: David S. Miller --- net/dsa/slave.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/net/dsa/slave.c b/net/dsa/slave.c index 527b1d5..48db91b 100644 --- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -21,6 +21,7 @@ #include #include #include +#include #include "dsa.h" #include "port.h" @@ -1056,10 +1057,10 @@ static void dsa_slave_get_strings(struct net_device *dev, if (stringset == ETH_SS_STATS) { int len = ETH_GSTRING_LEN; - strncpy(data, "tx_packets", len); - strncpy(data + len, "tx_bytes", len); - strncpy(data + 2 * len, "rx_packets", len); - strncpy(data + 3 * len, "rx_bytes", len); + strscpy_pad(data, "tx_packets", len); + strscpy_pad(data + len, "tx_bytes", len); + strscpy_pad(data + 2 * len, "rx_packets", len); + strscpy_pad(data + 3 * len, "rx_bytes", len); if (ds->ops->get_strings) ds->ops->get_strings(ds, dp->index, stringset, data + 4 * len); -- 2.7.4