Re: [PATCH v2] drm/gma500: refactor deprecated strncpy
On Tue, Sep 19, 2023 at 04:41:16AM +, Justin Stitt wrote: > `strncpy` is deprecated for use on NUL-terminated destination strings [1]. > > We should prefer more robust and less ambiguous string interfaces. > > Since `chan->base.name` is expected to be NUL-terminated, a suitable > replacement is `strscpy` [2] due to the fact that it guarantees > NUL-termination on the destination buffer without also unnecessarily > NUL-padding (since `chan` is kzalloc'd already). > > Link: > https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings > [1] > Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html > [2] > Link: https://github.com/KSPP/linux/issues/90 > Cc: linux-harden...@vger.kernel.org > Signed-off-by: Justin Stitt Applied to drm-misc-next. Thanks Patrik > --- > Changes in v2: > - use sizeof() instead of I2C_NAME_SIZE (thanks Kees, Patrik) > - Link to v1: > https://lore.kernel.org/r/20230914-drivers-gpu-drm-gma500-oaktrail_lvds_i2c-c-v1-1-0a53a076c...@google.com > --- > drivers/gpu/drm/gma500/oaktrail_lvds_i2c.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/gma500/oaktrail_lvds_i2c.c > b/drivers/gpu/drm/gma500/oaktrail_lvds_i2c.c > index 06b5b2d70d48..939c53fd09e8 100644 > --- a/drivers/gpu/drm/gma500/oaktrail_lvds_i2c.c > +++ b/drivers/gpu/drm/gma500/oaktrail_lvds_i2c.c > @@ -141,7 +141,7 @@ struct gma_i2c_chan *oaktrail_lvds_i2c_init(struct > drm_device *dev) > > chan->drm_dev = dev; > chan->reg = dev_priv->lpc_gpio_base; > - strncpy(chan->base.name, "gma500 LPC", I2C_NAME_SIZE - 1); > + strscpy(chan->base.name, "gma500 LPC", sizeof(chan->base.name)); > chan->base.owner = THIS_MODULE; > chan->base.algo_data = &chan->algo; > chan->base.dev.parent = dev->dev; > > --- > base-commit: 3669558bdf354cd352be955ef2764cde6a9bf5ec > change-id: 20230914-drivers-gpu-drm-gma500-oaktrail_lvds_i2c-c-a53c6d8bd62f > > Best regards, > -- > Justin Stitt >
Re: [PATCH v2] drm/gma500: refactor deprecated strncpy
On Tue, Sep 19, 2023 at 04:41:16AM +, Justin Stitt wrote: > `strncpy` is deprecated for use on NUL-terminated destination strings [1]. > > We should prefer more robust and less ambiguous string interfaces. > > Since `chan->base.name` is expected to be NUL-terminated, a suitable > replacement is `strscpy` [2] due to the fact that it guarantees > NUL-termination on the destination buffer without also unnecessarily > NUL-padding (since `chan` is kzalloc'd already). > > Link: > https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings > [1] > Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html > [2] > Link: https://github.com/KSPP/linux/issues/90 > Cc: linux-harden...@vger.kernel.org > Signed-off-by: Justin Stitt Thanks, looks good. If a v3 is needed, Subject can be improved to be "...: Replace strncpy with strscpy". Reviewed-by: Kees Cook -- Kees Cook
[PATCH v2] drm/gma500: refactor deprecated strncpy
`strncpy` is deprecated for use on NUL-terminated destination strings [1]. We should prefer more robust and less ambiguous string interfaces. Since `chan->base.name` is expected to be NUL-terminated, a suitable replacement is `strscpy` [2] due to the fact that it guarantees NUL-termination on the destination buffer without also unnecessarily NUL-padding (since `chan` is kzalloc'd already). Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2] Link: https://github.com/KSPP/linux/issues/90 Cc: linux-harden...@vger.kernel.org Signed-off-by: Justin Stitt --- Changes in v2: - use sizeof() instead of I2C_NAME_SIZE (thanks Kees, Patrik) - Link to v1: https://lore.kernel.org/r/20230914-drivers-gpu-drm-gma500-oaktrail_lvds_i2c-c-v1-1-0a53a076c...@google.com --- drivers/gpu/drm/gma500/oaktrail_lvds_i2c.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/gma500/oaktrail_lvds_i2c.c b/drivers/gpu/drm/gma500/oaktrail_lvds_i2c.c index 06b5b2d70d48..939c53fd09e8 100644 --- a/drivers/gpu/drm/gma500/oaktrail_lvds_i2c.c +++ b/drivers/gpu/drm/gma500/oaktrail_lvds_i2c.c @@ -141,7 +141,7 @@ struct gma_i2c_chan *oaktrail_lvds_i2c_init(struct drm_device *dev) chan->drm_dev = dev; chan->reg = dev_priv->lpc_gpio_base; - strncpy(chan->base.name, "gma500 LPC", I2C_NAME_SIZE - 1); + strscpy(chan->base.name, "gma500 LPC", sizeof(chan->base.name)); chan->base.owner = THIS_MODULE; chan->base.algo_data = &chan->algo; chan->base.dev.parent = dev->dev; --- base-commit: 3669558bdf354cd352be955ef2764cde6a9bf5ec change-id: 20230914-drivers-gpu-drm-gma500-oaktrail_lvds_i2c-c-a53c6d8bd62f Best regards, -- Justin Stitt
