[PATCH 0/3] leds/class: Fix string handling

[PATCH 0/3] leds/class: Fix string handling

[Ricardo Ribalda Delgado]

Fix errors reported by Geert Uytterhoeven.

I didn't have the chance to test the changes it in real hardware.


Ricardo Ribalda Delgado (3):
  leds/class: Use strlcpy instead of strncpy
  leds/class: Check snprintf return value
  leds/class: Set naming index as unsigned

 drivers/leds/led-class.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

-- 
2.1.4

[PATCH 1/3] leds/class: Use strlcpy instead of strncpy

[Ricardo Ribalda Delgado]

Strncpy does not guarantee a zero terminated string. Use strlcpy
instead.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
---
 drivers/leds/led-class.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index ebf6dad4f..294d6d6 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -224,7 +224,7 @@ static int led_classdev_next_name(const char *init_name, char *name,
 {
 	int i = 0;
 
-	strncpy(name, init_name, len);
+	strlcpy(name, init_name, len);
 
 	while (class_find_device(leds_class, NULL, name, match_name))
 		snprintf(name, len, "%s_%d", init_name, ++i);
-- 
2.1.4

[PATCH 2/3] leds/class: Check snprintf return value

[Ricardo Ribalda Delgado]

If the final name does not fit the string there is a potential
endless-loop.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
---
 drivers/leds/led-class.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 294d6d6..2ffe8b1 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -223,12 +223,17 @@ static int led_classdev_next_name(const char *init_name, char *name,
 				  size_t len)
 {
 	int i = 0;
+	int ret = 0;
 
 	strlcpy(name, init_name, len);
 
-	while (class_find_device(leds_class, NULL, name, match_name))
+	while (class_find_device(leds_class, NULL, name, match_name) &&
+	       (ret < len))
 		snprintf(name, len, "%s_%d", init_name, ++i);
 
+	if (ret >= len)
+		return -ENOMEM;
+
 	return i;
 }
 
@@ -243,6 +248,9 @@ int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
 	int ret;
 
 	ret = led_classdev_next_name(led_cdev->name, name, sizeof(name));
+	if (ret < 0)
+		return ret;
+
 	led_cdev->dev = device_create_with_groups(leds_class, parent, 0,
 				led_cdev, led_cdev->groups, "%s", name);
 	if (IS_ERR(led_cdev->dev))
-- 
2.1.4

Re: [PATCH 2/3] leds/class: Check snprintf return value

[Geert Uytterhoeven]

On Mon, Mar 30, 2015 at 10:55 AM, Ricardo Ribalda Delgado
<ricardo.ribalda@gmail.com> wrote:
> --- a/drivers/leds/led-class.c
> +++ b/drivers/leds/led-class.c
> @@ -223,12 +223,17 @@ static int led_classdev_next_name(const char *init_name, char *name,
>                                   size_t len)
>  {
>         int i = 0;
> +       int ret = 0;
>
>         strlcpy(name, init_name, len);
>
> -       while (class_find_device(leds_class, NULL, name, match_name))
> +       while (class_find_device(leds_class, NULL, name, match_name) &&
> +              (ret < len))
>                 snprintf(name, len, "%s_%d", init_name, ++i);

Missing "ret = "

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

[PATCH 3/3] leds/class: Set naming index as unsigned

[Ricardo Ribalda Delgado]

Avoid weird names (led_-65537) on overflows.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
---
 drivers/leds/led-class.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 2ffe8b1..2be1ba3 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -222,7 +222,7 @@ static int match_name(struct device *dev, const void *data)
 static int led_classdev_next_name(const char *init_name, char *name,
 				  size_t len)
 {
-	int i = 0;
+	unsigned int i = 0;
 	int ret = 0;
 
 	strlcpy(name, init_name, len);
-- 
2.1.4

Re: [PATCH 3/3] leds/class: Set naming index as unsigned

[Geert Uytterhoeven]

On Mon, Mar 30, 2015 at 10:55 AM, Ricardo Ribalda Delgado
<ricardo.ribalda@gmail.com> wrote:
> -       int i = 0;
> +       unsigned int i = 0;

That won't help, as you forgot to replace "%d" by "%u" in the snprintf()
call.

>         int ret = 0;

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH 0/3] leds/class: Fix string handling

[Bryan Wu]

On Mon, Mar 30, 2015 at 1:55 AM, Ricardo Ribalda Delgado
<ricardo.ribalda@gmail.com> wrote:
> Fix errors reported by Geert Uytterhoeven.
>
> I didn't have the chance to test the changes it in real hardware.
>
>

Thanks, Geert and Ricardo.
Ricardo, do you mind folding your fixing patches with original one
together and send it out again? I will use the new one to replace that
one in my tree, since this patch is not merged into Linus tree yet.

-Bryan


> Ricardo Ribalda Delgado (3):
>   leds/class: Use strlcpy instead of strncpy
>   leds/class: Check snprintf return value
>   leds/class: Set naming index as unsigned
>
>  drivers/leds/led-class.c | 14 +++++++++++---
>  1 file changed, 11 insertions(+), 3 deletions(-)
>
> --
> 2.1.4
>

Re: [PATCH 0/3] leds/class: Fix string handling

[Ricardo Ribalda Delgado]

Hello Bryan

On Mon, Mar 30, 2015 at 7:15 PM, Bryan Wu <cooloney@gmail.com> wrote:
> Thanks, Geert and Ricardo.
> Ricardo, do you mind folding your fixing patches with original one
> together and send it out again? I will use the new one to replace that
> one in my tree, since this patch is not merged into Linus tree yet.

Not at all, I have also added sakaris patches to my patchset so you
wont have any problem with them.
I dont know what are the conventions with s-o-b in this cases, so I
have left the defaults from git rebase

Thanks!

Re: [PATCH 0/3] leds/class: Fix string handling

[Bryan Wu]

On Mon, Mar 30, 2015 at 10:46 AM, Ricardo Ribalda Delgado
<ricardo.ribalda@gmail.com> wrote:
> Hello Bryan
>
> On Mon, Mar 30, 2015 at 7:15 PM, Bryan Wu <cooloney@gmail.com> wrote:
>> Thanks, Geert and Ricardo.
>> Ricardo, do you mind folding your fixing patches with original one
>> together and send it out again? I will use the new one to replace that
>> one in my tree, since this patch is not merged into Linus tree yet.
>
> Not at all, I have also added sakaris patches to my patchset so you
> wont have any problem with them.
> I dont know what are the conventions with s-o-b in this cases, so I
> have left the defaults from git rebase
>
> Thanks!

Good, I will handle that.
Thanks,
-Bryan