Re: [kernel-hardening] Re: [PATCH v2] kernel: escape non-ASCII andcontrol characters in printk()

From: Alan Cox
Date: Fri Jul 01 2011 - 10:18:55 EST


> $ dmesg | tail
> ...
> [16291.982492] init[21579]: segfault at 0 ip 00007f527186028a sp 00007fff08251dd8 error 4 in libc-2.11.1.so[7f52717d8000+17a000]
> [16379.001357] fail[21586]: segfault at 0 ip 00007f332831028a sp 00007fffc52de568 error 4 in libc-2.11.1.so[7f3328288000+17a000]
> $
> (see 1234 => init change)
>
> As you see here, the previous log entry was showed not as it was
> initally logged. Core dump message was chosen fully arbitrary, just to
> show that some specific part of it can be "edited".

Your syslog daemon appears to need improvement and that would be the
right fix for dmesg etc.

The other case is the actual printk direct to console case, particularly
on a serial port. That one actually has more potential for actual
annoyance.



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