Question about /proc/kmsg semantics..

Question about /proc/kmsg semantics..

[Michael Bacarella]

Two pronged:

I've seen a couple of patches in the archives to make open()/close()
on /proc/kmsg do more than NOP. As of 2.4.4, klogd still needs to
run as root since access is checked on read() rather than once at
open(). I can't find the rationale as to why they're rejected.

Also, why is reading /proc/kmsg a privileged operation, yet dmesg
can happily print out the entire ring via (do_)syslog() ?

Thanks

-- 
Michael Bacarella <mbac@nyct.net>
Technical Staff / System Development,
New York Connect.Net, Ltd.

Re: Question about /proc/kmsg semantics..

[H. Peter Anvin]

Followup to:  <20010501005237.A2776@sync.nyct.net>
By author:    Michael Bacarella <mbac@nyct.net>
In newsgroup: linux.dev.kernel
> 
> I've seen a couple of patches in the archives to make open()/close()
> on /proc/kmsg do more than NOP. As of 2.4.4, klogd still needs to
> run as root since access is checked on read() rather than once at
> open(). I can't find the rationale as to why they're rejected.
> 
> Also, why is reading /proc/kmsg a privileged operation, yet dmesg
> can happily print out the entire ring via (do_)syslog() ?
> 

Probably because reading /proc/kmsg may cause syslogd to miss
messages.

	-hpa
-- 
<hpa@transmeta.com> at work, <hpa@zytor.com> in private!
"Unix gives you enough rope to shoot yourself in the foot."
http://www.zytor.com/~hpa/puzzle.txt