Re: [PATCH v2 1/6] leds: netdev trigger: use memcpy in device_name_store

[Pavel Machek]

On Thu 2019-03-14 15:06:14, Rasmus Villemoes wrote:
> If userspace doesn't end the input with a newline (which can easily
> happen if the write happens from a C program that does write(fd,
> iface, strlen(iface))), we may end up including garbage from a
> previous, longer value in the device_name. For example
> 
> # cat device_name
> 
> # printf 'eth12' > device_name
> # cat device_name
> eth12
> # printf 'eth3' > device_name
> # cat device_name
> eth32
> 
> I highly doubt anybody is relying on this behaviour, so switch to
> simply copying the bytes (we've already checked that size is <
> IFNAMSIZ) and unconditionally zero-terminate it; of course, we also
> still have to strip a trailing newline.
> 
> This is also preparation for future patches.
> 
> Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>

Acked-by: Pavel Machek <pavel@xxxxxx>

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