On Wed, 2012-06-06 at 02:13 +0200, Kay Sievers wrote:

The question is what happens if you inject your new binary two-byte prefix, like: echo -e "\x01\x02Hello" > /dev/kmsg

It's not a 2 byte binary. It's a leading ascii SOH and a standard ascii char '0' ... '7' or 'd'.

#define KERN_EMERG KERN_SOH "0" /* system is unusable */ #define KERN_ALERT KERN_SOH "1" /* action must be taken immediately */ etc...

And if that changes the log-level to "2" instead of the default "4"?

No it doesn't.

It's not triggering that because devkmsg_writev does prefix parsing only on the old "<n>" form.