Re: [PATCH v3 04/11] syslog_ns: make syslog handling per namespace

On Wed, 2013-08-07 at 15:37 +0800, Rui Xiang wrote:

This patch makes syslog buf and other fields per
namespace.

Here use ns->log_buf(log_buf_len, logbuf_lock,
log_first_seq, logbuf_lock, and so on) fields
instead of global ones to handle syslog.

[...]

[...]

 }
 
-#ifdef CONFIG_SECURITY_DMESG_RESTRICT
-int dmesg_restrict = 1;
-#else
-int dmesg_restrict;
-#endif
-
-static int syslog_action_restricted(int type)
+static int syslog_action_restricted(int type,
+			struct syslog_namespace *ns)
 {
-	if (dmesg_restrict)
+	if (ns->dmesg_restrict)
 		return 1;
 	/*
 	 * Unless restricted, we allow "read all" and "get buffer size"

[...]

I don't think this should be a per-namespace setting.  And it certainly
should not be possible for child namespaces to disable dmesg_restrict if
it is enabled by a parent namespace.

In later patches, it appears to be copied into child namespaces but not
made visible or controllable there.  So if an administrator enables
dmesg_restrict in the initial syslog namespace after another syslog
namespace has been created, she won't be able to tell that it is still
disabled in that other namespace.

Ben.

-- 
Ben Hutchings, Staff Engineer, Solarflare
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They asked us to note that Solarflare product names are trademarked.