| Message ID | 20240408-strncpy-drivers-net-dsa-lan9303-core-c-v3-1-0c313694d25b@google.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v3] net: dsa: lan9303: use ethtool_puts() for lan9303_get_strings() | expand |
On Mon, Apr 08, 2024 at 09:01:57PM +0000, Justin Stitt wrote: > This pattern of strncpy with some pointer arithmetic setting fixed-sized > intervals with string literal data is a bit weird so let's use > ethtool_puts() as this has more obvious behavior and is less-error > prone. > > Nicely, we also get to drop a usage of the now deprecated strncpy() [1]. > > Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] > Link: https://github.com/KSPP/linux/issues/90 > Cc: linux-hardening@vger.kernel.org > Cc: Kees Cook <keescook@chromium.org> > Signed-off-by: Justin Stitt <justinstitt@google.com> Reviewed-by: Kees Cook <keescook@chromium.org>
From: Justin Stitt <justinstitt@google.com> Date: Mon, 08 Apr 2024 21:01:57 +0000 > This pattern of strncpy with some pointer arithmetic setting fixed-sized > intervals with string literal data is a bit weird so let's use > ethtool_puts() as this has more obvious behavior and is less-error > prone. > > Nicely, we also get to drop a usage of the now deprecated strncpy() [1]. > > Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] > Link: https://github.com/KSPP/linux/issues/90 > Cc: linux-hardening@vger.kernel.org > Cc: Kees Cook <keescook@chromium.org> > Signed-off-by: Justin Stitt <justinstitt@google.com> > Suggested-by: Alexander Lobakin <aleksander.lobakin@intel.com> > --- > Changes in v3: > - use ethtool_puts over ethtool_sprintf > - Link to v2: https://lore.kernel.org/r/20231005-strncpy-drivers-net-dsa-lan9303-core-c-v2-1-feb452a532db@google.com > > Changes in v2: > - use ethtool_sprintf (thanks Alexander) > - Link to v1: https://lore.kernel.org/r/20231005-strncpy-drivers-net-dsa-lan9303-core-c-v1-1-5a66c538147e@google.com > --- > drivers/net/dsa/lan9303-core.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/dsa/lan9303-core.c b/drivers/net/dsa/lan9303-core.c > index fcb20eac332a..04d3af0eb28e 100644 > --- a/drivers/net/dsa/lan9303-core.c > +++ b/drivers/net/dsa/lan9303-core.c > @@ -1007,14 +1007,14 @@ static const struct lan9303_mib_desc lan9303_mib[] = { > static void lan9303_get_strings(struct dsa_switch *ds, int port, > u32 stringset, uint8_t *data) > { > + u8 *buf = data; > unsigned int u; > > if (stringset != ETH_SS_STATS) > return; > > for (u = 0; u < ARRAY_SIZE(lan9303_mib); u++) { > - strncpy(data + u * ETH_GSTRING_LEN, lan9303_mib[u].name, > - ETH_GSTRING_LEN); > + ethtool_puts(&buf, lan9303_mib[u].name); > } The braces { } around ethtool_puts() aren't needed anymore. > } > > > --- > base-commit: c85af715cac0a951eea97393378e84bb49384734 > change-id: 20231005-strncpy-drivers-net-dsa-lan9303-core-c-6386858e5c22 > > Best regards, > -- > Justin Stitt <justinstitt@google.com> Thanks, Olek
diff --git a/drivers/net/dsa/lan9303-core.c b/drivers/net/dsa/lan9303-core.c index fcb20eac332a..04d3af0eb28e 100644 --- a/drivers/net/dsa/lan9303-core.c +++ b/drivers/net/dsa/lan9303-core.c @@ -1007,14 +1007,14 @@ static const struct lan9303_mib_desc lan9303_mib[] = { static void lan9303_get_strings(struct dsa_switch *ds, int port, u32 stringset, uint8_t *data) { + u8 *buf = data; unsigned int u; if (stringset != ETH_SS_STATS) return; for (u = 0; u < ARRAY_SIZE(lan9303_mib); u++) { - strncpy(data + u * ETH_GSTRING_LEN, lan9303_mib[u].name, - ETH_GSTRING_LEN); + ethtool_puts(&buf, lan9303_mib[u].name); } }
This pattern of strncpy with some pointer arithmetic setting fixed-sized intervals with string literal data is a bit weird so let's use ethtool_puts() as this has more obvious behavior and is less-error prone. Nicely, we also get to drop a usage of the now deprecated strncpy() [1]. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Link: https://github.com/KSPP/linux/issues/90 Cc: linux-hardening@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Justin Stitt <justinstitt@google.com> Suggested-by: Alexander Lobakin <aleksander.lobakin@intel.com> --- Changes in v3: - use ethtool_puts over ethtool_sprintf - Link to v2: https://lore.kernel.org/r/20231005-strncpy-drivers-net-dsa-lan9303-core-c-v2-1-feb452a532db@google.com Changes in v2: - use ethtool_sprintf (thanks Alexander) - Link to v1: https://lore.kernel.org/r/20231005-strncpy-drivers-net-dsa-lan9303-core-c-v1-1-5a66c538147e@google.com --- drivers/net/dsa/lan9303-core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- base-commit: c85af715cac0a951eea97393378e84bb49384734 change-id: 20231005-strncpy-drivers-net-dsa-lan9303-core-c-6386858e5c22 Best regards, -- Justin Stitt <justinstitt@google.com>