Re: file caps: permit unsafe signaling when CONFIG_FS_CAPS=n

["Serge E. Hallyn" <serue@us.ibm.com>]

Quoting Serge E. Hallyn (serue@us.ibm.com):
> Ok, the following patch restores the CONFIG_FS_CAPS=n signaling
> behavior, but I'm having a config problem.  When
> CONFIG_SECURITY_CAPABILITIES=n, and I toggle
> CONFIG_SECURITY_FS_CAPABILITIES between y and n, security/commoncap.o
> does not recompile.  However since capabilities are now the default
> security module, commoncap.o is in fact included in the kernel build,
> and therefore should be recompiled.
> 
> Looking into why, but maybe someone knows offhand what would be going
> wrong?

Uh, never mind.  It does the right thing.  CONFIG_SECURITY=n means we
use capabilities, but CONFIG_SECURITY=y and CONFIG_SECURITY_CAPABILITIES=n 
means we use dummy.  The following patch fixes the Kconfig accordingly.

From: Serge E. Hallyn <serue@us.ibm.com>
Subject: [PATCH 1/1] file caps: don't show FILE_CAPABILITIES option when not relevant

FILE_CAPABILITIES are relevant when CONFIG_SECURITY=n, but not when
CONFIG_SECURITY=y && CONFIG_SECURITY_CAPABILITIES=n.  So make
CONFIG_SECURITY_FS_CAPABILITIES depend on the right conditions.

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
---
 security/Kconfig |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/security/Kconfig b/security/Kconfig
index 6c9d69e..1b47f01 100644
--- a/security/Kconfig
+++ b/security/Kconfig
@@ -82,6 +82,7 @@ config SECURITY_CAPABILITIES
 
 config SECURITY_FS_CAPABILITIES
 	bool "File POSIX Capabilities"
+	depends on SECURITY=n || SECURITY_CAPABILITIES=y
 	default n
 	help
 	  This enables filesystem capabilities, allowing you to give
-- 
1.4.1