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Date: Fri, 13 Mar 2015 11:37:45 +0000
From: Marek Kroemeke <>
Subject: Re: Disabling reading of kernel log buffer reading
 for user

echo 1 > /proc/sys/kernel/dmesg_restrict

> Hash: SHA1
> Hello List,
> After years working on Linux, I just found out, that any user not only root can read the kernel log buffer - I never even considered that this could be the case.
> As this behavior is documented and expected, this is not a security vulnerability. But to avoid things like in [1], I would like to disable that on my machines.
> Questions:
> * What would be the side effects of making /dev/kmesg only root accessible? Maybe syslog not able to write kmessages to log?
> * Would it be safe to disable the syslog syscall for action SYSLOG_ACTION_READ_* and all users except root and syslog? Does someone have tested selinux config for that?
> hd
> [1]
> - -- 
> PGP: 156A AE98 B91F 0114 FE88  2BD8 C459 9386 feed a bee
> Version: GnuPG v1
> VusAnRUCtETL9IGmaeSyQUt2dyCQgCpV
> =Krnc

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