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Commit 84088ba2 authored by Jarkko Sakkinen's avatar Jarkko Sakkinen Committed by Casey Schaufler
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Smack: domain transition protections (v3)



Protections for domain transition:

- BPRM unsafe flags
- Secureexec
- Clear unsafe personality bits.
- Clear parent death signal

Signed-off-by: default avatarJarkko Sakkinen <jarkko.sakkinen@intel.com>
parent 975d5e55
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+42 −11
Original line number Diff line number Diff line
@@ -5,12 +5,13 @@
 *
 *  Authors:
 *	Casey Schaufler <casey@schaufler-ca.com>
 *	Jarkko Sakkinen <ext-jarkko.2.sakkinen@nokia.com>
 *	Jarkko Sakkinen <jarkko.sakkinen@intel.com>
 *
 *  Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com>
 *  Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
 *                Paul Moore <paul@paul-moore.com>
 *  Copyright (C) 2010 Nokia Corporation
 *  Copyright (C) 2011 Intel Corporation.
 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
@@ -449,9 +450,9 @@ static int smack_sb_umount(struct vfsmount *mnt, int flags)
 */
static int smack_bprm_set_creds(struct linux_binprm *bprm)
{
	struct task_smack *tsp = bprm->cred->security;
	struct inode *inode = bprm->file->f_path.dentry->d_inode;
	struct task_smack *bsp = bprm->cred->security;
	struct inode_smack *isp;
	struct dentry *dp;
	int rc;

	rc = cap_bprm_set_creds(bprm);
@@ -461,20 +462,48 @@ static int smack_bprm_set_creds(struct linux_binprm *bprm)
	if (bprm->cred_prepared)
		return 0;

	if (bprm->file == NULL || bprm->file->f_dentry == NULL)
	isp = inode->i_security;
	if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task)
		return 0;

	dp = bprm->file->f_dentry;
	if (bprm->unsafe)
		return -EPERM;

	bsp->smk_task = isp->smk_task;
	bprm->per_clear |= PER_CLEAR_ON_SETID;

	if (dp->d_inode == NULL)
	return 0;
}

	isp = dp->d_inode->i_security;
/**
 * smack_bprm_committing_creds - Prepare to install the new credentials
 * from bprm.
 *
 * @bprm: binprm for exec
 */
static void smack_bprm_committing_creds(struct linux_binprm *bprm)
{
	struct task_smack *bsp = bprm->cred->security;

	if (isp->smk_task != NULL)
		tsp->smk_task = isp->smk_task;
	if (bsp->smk_task != bsp->smk_forked)
		current->pdeath_signal = 0;
}

	return 0;
/**
 * smack_bprm_secureexec - Return the decision to use secureexec.
 * @bprm: binprm for exec
 *
 * Returns 0 on success.
 */
static int smack_bprm_secureexec(struct linux_binprm *bprm)
{
	struct task_smack *tsp = current_security();
	int ret = cap_bprm_secureexec(bprm);

	if (!ret && (tsp->smk_task != tsp->smk_forked))
		ret = 1;

	return ret;
}

/*
@@ -3467,6 +3496,8 @@ struct security_operations smack_ops = {
	.sb_umount = 			smack_sb_umount,

	.bprm_set_creds =		smack_bprm_set_creds,
	.bprm_committing_creds =	smack_bprm_committing_creds,
	.bprm_secureexec =		smack_bprm_secureexec,

	.inode_alloc_security = 	smack_inode_alloc_security,
	.inode_free_security = 		smack_inode_free_security,