Subject: Re: BUG at security/selinux/avc.c:883 (was: Re: linux-next: Tree for July 17: early crash on x86-64)

From: Al Viro <[email-masked]>
Date: Sun, 20 Jul 2008 13:15:59 +0100

On Sun, Jul 20, 2008 at 11:42:53AM +0200, Thomas Meyer wrote:
> Am Sonntag, den 20.07.2008, 05:54 +1000 schrieb James Morris:
> > On Sat, 19 Jul 2008, Rafael J. Wysocki wrote:
> > 
> > > > vfs-next/net-next conflict; apply the patch below on top of the
> > merge.
> > > 
> > > That helped, thanks.
> > > 
> > > But next it ran into the BUG_ON() in line 883 of
> > security/selinux/avc.c .
> > > Disabling selinux made the kernel boot, finally.
> > 
> > Ugh, that's not supposed to happen.  Where was this in the boot?  Do
> > you 
> > have a console log?

Argh...  Fallout from ->permission() patch series.  I've folded that into
rebase (along with Randy's compile fixes and missing bit in capability.c
in ->inode_permission() patch; AFAICS takes care of all mismerges as well).
In the meanwhile, see the patch below on top of next-20080718:

diff --git a/fs/namei.c b/fs/namei.c
index a15c155..c0a64e2 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -286,7 +286,8 @@ int permission(struct inode *inode, int mask, struct nameidata *nd)
 	if (retval)
 		return retval;
 
-	return security_inode_permission(inode, mask);
+	return security_inode_permission(inode,
+					mask & (MAY_READ|MAY_WRITE|MAY_EXEC));
 }
 
 /**