2019-09-05 23:02:59

by J. Bruce Fields

Subject: [PATCH 2/9] thunderbolt: show key using %*s not %*pE

From: "J. Bruce Fields" <[email protected]>

%*pEp (without "h" or "o") is a no-op. This string could contain
arbitrary (non-NULL) characters, so we do want escaping. Use %*pE like
every other caller.

Signed-off-by: J. Bruce Fields <[email protected]>
---
drivers/thunderbolt/xdomain.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c
index 5118d46702d5..4e17a7c7bf0a 100644
--- a/drivers/thunderbolt/xdomain.c
+++ b/drivers/thunderbolt/xdomain.c
@@ -636,7 +636,7 @@ static ssize_t key_show(struct device *dev, struct device_attribute *attr,
* It should be null terminated but anything else is pretty much
* allowed.
*/
- return sprintf(buf, "%*pEp\n", (int)strlen(svc->key), svc->key);
+ return sprintf(buf, "%*pE\n", (int)strlen(svc->key), svc->key);
}
static DEVICE_ATTR_RO(key);

--
2.21.0

2019-09-06 08:46:25

by Kees Cook

Subject: Re: [PATCH 2/9] thunderbolt: show key using %*s not %*pE

On Thu, Sep 05, 2019 at 03:44:26PM -0400, J. Bruce Fields wrote:
> From: "J. Bruce Fields" <[email protected]>
>
> %*pEp (without "h" or "o") is a no-op. This string could contain
> arbitrary (non-NULL) characters, so we do want escaping. Use %*pE like
> every other caller.

Agreed on all counts. pEp is actively resulting in NO escaping, which is
a bug here.

Acked-by: Kees Cook <[email protected]>

-Kees

>
> Signed-off-by: J. Bruce Fields <[email protected]>
> ---
> drivers/thunderbolt/xdomain.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c
> index 5118d46702d5..4e17a7c7bf0a 100644
> --- a/drivers/thunderbolt/xdomain.c
> +++ b/drivers/thunderbolt/xdomain.c
> @@ -636,7 +636,7 @@ static ssize_t key_show(struct device *dev, struct device_attribute *attr,
> * It should be null terminated but anything else is pretty much
> * allowed.
> */
> - return sprintf(buf, "%*pEp\n", (int)strlen(svc->key), svc->key);
> + return sprintf(buf, "%*pE\n", (int)strlen(svc->key), svc->key);
> }
> static DEVICE_ATTR_RO(key);
>
> --
> 2.21.0
>

--
Kees Cook

2019-09-10 18:39:00

by Joe Perches

Subject: Re: [PATCH 2/9] thunderbolt: show key using %*s not %*pE

On Thu, 2019-09-05 at 15:44 -0400, J. Bruce Fields wrote:
> From: "J. Bruce Fields" <[email protected]>
>
> %*pEp (without "h" or "o") is a no-op. This string could contain
> arbitrary (non-NULL) characters, so we do want escaping. Use %*pE like
> every other caller.
[]
> diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c
[]
> @@ -636,7 +636,7 @@ static ssize_t key_show(struct device *dev, struct device_attribute *attr,
> * It should be null terminated but anything else is pretty much
> * allowed.
> */
> - return sprintf(buf, "%*pEp\n", (int)strlen(svc->key), svc->key);
> + return sprintf(buf, "%*pE\n", (int)strlen(svc->key), svc->key);

The code does not match the patch subject / commit title.