Greg, I assume you'll deal with this one? Just let me know if I
should do something with it.
On Mon, Sep 11, 2017 at 09:45:42AM +0200, Nicolai Stange wrote:
> When printing the driver_override parameter when it is 4095 and 4094 bytes
> long, the printing code would access invalid memory because we need count+1
> bytes for printing.
>
> Reject driver_override values of these lengths in driver_override_store().
>
> This is in close analogy to commit 4efe874aace5 ("PCI: Don't read past the
> end of sysfs "driver_override" buffer") from Sasha Levin.
>
> Fixes: 3d713e0e382e ("driver core: platform: add device binding path 'driver_override'")
> Cc: stable@xxxxxxxxxxxxxxx # v3.17+
> Signed-off-by: Nicolai Stange <nstange@xxxxxxx>
> ---
> drivers/base/platform.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/base/platform.c b/drivers/base/platform.c
> index d1bd99271066..9045c5f3734e 100644
> --- a/drivers/base/platform.c
> +++ b/drivers/base/platform.c
> @@ -868,7 +868,8 @@ static ssize_t driver_override_store(struct device *dev,
> struct platform_device *pdev = to_platform_device(dev);
> char *driver_override, *old, *cp;
>
> - if (count > PATH_MAX)
> + /* We need to keep extra room for a newline */
> + if (count >= (PAGE_SIZE - 1))
> return -EINVAL;
>
> driver_override = kstrndup(buf, count, GFP_KERNEL);
> --
> 2.13.5
>
