Commit b197367e authored by Andreas Gruenbacher's avatar Andreas Gruenbacher Committed by Paul Moore
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selinux: Inode label revalidation performance fix 



Commit 5d226df4 has introduced a performance regression of about
10% in the UnixBench pipe benchmark.  It turns out that the call
to inode_security in selinux_file_permission can be moved below
the zero-mask test and that inode_security_revalidate can be
removed entirely, which brings us back to roughly the original
performance.

Signed-off-by: default avatarAndreas Gruenbacher <agruenba@redhat.com>
Acked-by: default avatarStephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: default avatarPaul Moore <paul@paul-moore.com>
parent 76319946

security/selinux/hooks.c

+2 −8
Original line number Diff line number Diff line
@@ -273,11 +273,6 @@ static int __inode_security_revalidate(struct inode *inode, 
	return 0;

}



static void inode_security_revalidate(struct inode *inode)

{

	__inode_security_revalidate(inode, NULL, true);

}



static struct inode_security_struct *inode_security_novalidate(struct inode *inode)

{

	return inode->i_security;
@@ -3277,19 +3272,19 @@ static int selinux_file_permission(struct file *file, int mask) 
{

	struct inode *inode = file_inode(file);

	struct file_security_struct *fsec = file->f_security;

	struct inode_security_struct *isec = inode_security(inode);

	struct inode_security_struct *isec;

	u32 sid = current_sid();



	if (!mask)

		/* No permission to check.  Existence test. */

		return 0;



	isec = inode_security(inode);

	if (sid == fsec->sid && fsec->isid == isec->sid &&

	    fsec->pseqno == avc_policy_seqno())

		/* No change since file_open check. */

		return 0;



	inode_security_revalidate(inode);

	return selinux_revalidate_file_permission(file, mask);

}
@@ -3595,7 +3590,6 @@ static int selinux_file_open(struct file *file, const struct cred *cred) 
	 * new inode label or new policy.

	 * This check is not redundant - do not remove.

	 */

	inode_security_revalidate(file_inode(file));

	return file_path_has_perm(cred, file, open_file_to_av(file));

}

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