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: [email protected]
Cc: Kees Cook <[email protected]>
Signed-off-by: Justin Stitt <[email protected]>
Suggested-by: Alexander Lobakin <[email protected]>
---
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);
}
}
---
base-commit: c85af715cac0a951eea97393378e84bb49384734
change-id: 20231005-strncpy-drivers-net-dsa-lan9303-core-c-6386858e5c22
Best regards,
--
Justin Stitt <[email protected]>
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: [email protected]
> Cc: Kees Cook <[email protected]>
> Signed-off-by: Justin Stitt <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
--
Kees Cook
From: Justin Stitt <[email protected]>
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: [email protected]
> Cc: Kees Cook <[email protected]>
> Signed-off-by: Justin Stitt <[email protected]>
> Suggested-by: Alexander Lobakin <[email protected]>
> ---
> 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 <[email protected]>
Thanks,
Olek