diff options
| author | Jarkko Sakkinen <jarkko.sakkinen@intel.com> | 2011-10-07 09:27:53 +0300 |
|---|---|---|
| committer | Casey Schaufler <cschaufler@cschaufler-intel.(none)> | 2011-10-12 14:28:15 -0700 |
| commit | 84088ba239293abb24260c6c36d86e8775b6707f (patch) | |
| tree | 7a8936d22156d108241725fae705979316fc6350 /security/smack | |
| parent | 975d5e55c2e78b755bd0b92b71db1c241c5a2665 (diff) | |
| download | lwn-84088ba239293abb24260c6c36d86e8775b6707f.tar.gz lwn-84088ba239293abb24260c6c36d86e8775b6707f.zip | |
Smack: domain transition protections (v3)
Protections for domain transition:
- BPRM unsafe flags
- Secureexec
- Clear unsafe personality bits.
- Clear parent death signal
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Diffstat (limited to 'security/smack')
| -rw-r--r-- | security/smack/smack_lsm.c | 53 |
1 files changed, 42 insertions, 11 deletions
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index dab8af17ef38..d55b991268d5 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -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; - if (dp->d_inode == NULL) - return 0; + bsp->smk_task = isp->smk_task; + bprm->per_clear |= PER_CLEAR_ON_SETID; - isp = dp->d_inode->i_security; + return 0; +} - if (isp->smk_task != NULL) - tsp->smk_task = isp->smk_task; +/** + * 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; - return 0; + if (bsp->smk_task != bsp->smk_forked) + current->pdeath_signal = 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, |