[06/25] Smack: Abstract the cred security blob

Message ID	eded2e70-e5dc-fa67-cd0b-6bf41bd07bc3@schaufler-ca.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <linux-security-module-owner@kernel.org> Subject: [PATCH 06/25] Smack: Abstract the cred security blob To: LSM <linux-security-module@vger.kernel.org>, James Morris <jmorris@namei.org> References: <801ef9a9-e594-387c-f285-8d90879ee2bf@schaufler-ca.com> Cc: John Johansen <john.johansen@canonical.com>, Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>, Paul Moore <paul@paul-moore.com>, Stephen Smalley <sds@tycho.nsa.gov> From: Casey Schaufler <casey@schaufler-ca.com> Message-ID: <eded2e70-e5dc-fa67-cd0b-6bf41bd07bc3@schaufler-ca.com> Date: Sat, 13 Aug 2016 13:35:53 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: <801ef9a9-e594-387c-f285-8d90879ee2bf@schaufler-ca.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk

diff --git a/security/smack/smack.h b/security/smack/smack.h index 26e58f1..8849706 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -24,6 +24,7 @@ #include <linux/list.h> #include <linux/rculist.h> #include <linux/lsm_audit.h> +#include <linux/msg.h> /* * Use IPv6 port labeling if IPv6 is enabled and secmarks @@ -343,6 +344,11 @@ extern struct list_head smack_onlycap_list; #define SMACK_HASH_SLOTS 16 extern struct hlist_head smack_known_hash[SMACK_HASH_SLOTS]; +static inline struct task_smack *smack_cred(const struct cred *cred) +{ + return cred->security; +} + /* * Is the directory transmuting? */ @@ -369,13 +375,16 @@ static inline struct smack_known *smk_of_task(const struct task_smack *tsp) return tsp->smk_task; } -static inline struct smack_known *smk_of_task_struct(const struct task_struct *t) +static inline struct smack_known *smk_of_task_struct( + const struct task_struct *t) { struct smack_known *skp; + const struct cred *cred; rcu_read_lock(); - skp = smk_of_task(__task_cred(t)->security); + cred = __task_cred(t); rcu_read_unlock(); + skp = smk_of_task(smack_cred(cred)); return skp; } @@ -392,7 +401,7 @@ static inline struct smack_known *smk_of_forked(const struct task_smack *tsp) */ static inline struct smack_known *smk_of_current(void) { - return smk_of_task(current_security()); + return smk_of_task(smack_cred(current_cred())); } /* diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c index 23e5808..9393ef4 100644 --- a/security/smack/smack_access.c +++ b/security/smack/smack_access.c @@ -280,7 +280,7 @@ out_audit: int smk_curacc(struct smack_known *obj_known, u32 mode, struct smk_audit_info *a) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); return smk_tskacc(tsp, obj_known, mode, a); } diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 7cbc72e..bc4126e 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -120,7 +120,7 @@ static int smk_bu_note(char *note, struct smack_known *sskp, static int smk_bu_current(char *note, struct smack_known *oskp, int mode, int rc) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); char acc[SMK_NUM_ACCESS_TYPE + 1]; if (rc <= 0) @@ -141,7 +141,7 @@ static int smk_bu_current(char *note, struct smack_known *oskp, #ifdef CONFIG_SECURITY_SMACK_BRINGUP static int smk_bu_task(struct task_struct *otp, int mode, int rc) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); struct smack_known *smk_task = smk_of_task_struct(otp); char acc[SMK_NUM_ACCESS_TYPE + 1]; @@ -163,7 +163,7 @@ static int smk_bu_task(struct task_struct *otp, int mode, int rc) #ifdef CONFIG_SECURITY_SMACK_BRINGUP static int smk_bu_inode(struct inode *inode, int mode, int rc) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); struct inode_smack *isp = inode->i_security; char acc[SMK_NUM_ACCESS_TYPE + 1]; @@ -193,7 +193,7 @@ static int smk_bu_inode(struct inode *inode, int mode, int rc) #ifdef CONFIG_SECURITY_SMACK_BRINGUP static int smk_bu_file(struct file *file, int mode, int rc) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); struct smack_known *sskp = tsp->smk_task; struct inode *inode = file_inode(file); struct inode_smack *isp = inode->i_security; @@ -223,7 +223,7 @@ static int smk_bu_file(struct file *file, int mode, int rc) static int smk_bu_credfile(const struct cred *cred, struct file *file, int mode, int rc) { - struct task_smack *tsp = cred->security; + struct task_smack *tsp = smack_cred(cred); struct smack_known *sskp = tsp->smk_task; struct inode *inode = file->f_inode; struct inode_smack *isp = inode->i_security; @@ -307,6 +307,23 @@ static struct inode_smack *new_inode_smack(struct smack_known *skp) } /** + * init_task_smack - initialize a task security blob + * @tsp: blob to initialize + * @task: a pointer to the Smack label for the running task + * @forked: a pointer to the Smack label for the forked task + * + */ +static void init_task_smack(struct task_smack *tsp, struct smack_known *task, + struct smack_known *forked) +{ + tsp->smk_task = task; + tsp->smk_forked = forked; + INIT_LIST_HEAD(&tsp->smk_rules); + INIT_LIST_HEAD(&tsp->smk_relabel); + mutex_init(&tsp->smk_rules_lock); +} + +/** * new_task_smack - allocate a task security blob * @task: a pointer to the Smack label for the running task * @forked: a pointer to the Smack label for the forked task @@ -323,12 +340,7 @@ static struct task_smack *new_task_smack(struct smack_known *task, if (tsp == NULL) return NULL; - tsp->smk_task = task; - tsp->smk_forked = forked; - INIT_LIST_HEAD(&tsp->smk_rules); - INIT_LIST_HEAD(&tsp->smk_relabel); - mutex_init(&tsp->smk_rules_lock); - + init_task_smack(tsp, task, forked); return tsp; } @@ -431,7 +443,7 @@ static int smk_ptrace_rule_check(struct task_struct *tracer, } rcu_read_lock(); - tsp = __task_cred(tracer)->security; + tsp = smack_cred(__task_cred(tracer)); tracer_known = smk_of_task(tsp); if ((mode & PTRACE_MODE_ATTACH) && @@ -498,7 +510,7 @@ static int smack_ptrace_traceme(struct task_struct *ptp) int rc; struct smack_known *skp; - skp = smk_of_task(current_security()); + skp = smk_of_task(smack_cred(current_cred())); rc = smk_ptrace_rule_check(ptp, skp, PTRACE_MODE_ATTACH, __func__); return rc; @@ -917,7 +929,7 @@ static int smack_sb_statfs(struct dentry *dentry) static int smack_bprm_set_creds(struct linux_binprm *bprm) { struct inode *inode = file_inode(bprm->file); - struct task_smack *bsp = bprm->cred->security; + struct task_smack *bsp = smack_cred(bprm->cred); struct inode_smack *isp; struct superblock_smack *sbsp; int rc; @@ -966,7 +978,7 @@ static int smack_bprm_set_creds(struct linux_binprm *bprm) */ static void smack_bprm_committing_creds(struct linux_binprm *bprm) { - struct task_smack *bsp = bprm->cred->security; + struct task_smack *bsp = smack_cred(bprm->cred); if (bsp->smk_task != bsp->smk_forked) current->pdeath_signal = 0; @@ -980,7 +992,7 @@ static void smack_bprm_committing_creds(struct linux_binprm *bprm) */ static int smack_bprm_secureexec(struct linux_binprm *bprm) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); if (tsp->smk_task != tsp->smk_forked) return 1; @@ -1749,7 +1761,7 @@ static int smack_mmap_file(struct file *file, return -EACCES; mkp = isp->smk_mmap; - tsp = current_security(); + tsp = smack_cred(current_cred()); skp = smk_of_current(); rc = 0; @@ -1845,7 +1857,7 @@ static int smack_file_send_sigiotask(struct task_struct *tsk, struct fown_struct *fown, int signum) { struct smack_known *skp; - struct smack_known *tkp = smk_of_task(tsk->cred->security); + struct smack_known *tkp = smk_of_task(smack_cred(tsk->cred)); struct file *file; int rc; struct smk_audit_info ad; @@ -1893,7 +1905,7 @@ static int smack_file_receive(struct file *file) if (S_ISSOCK(inode->i_mode)) { sock = SOCKET_I(inode); ssp = sock->sk->sk_security; - tsp = current_security(); + tsp = smack_cred(current_cred()); /* * If the receiving process can't write to the * passed socket or if the passed socket can't @@ -1935,7 +1947,7 @@ static int smack_file_receive(struct file *file) */ static int smack_file_open(struct file *file, const struct cred *cred) { - struct task_smack *tsp = cred->security; + struct task_smack *tsp = smack_cred(cred); struct inode *inode = file_inode(file); struct smk_audit_info ad; int rc; @@ -1966,9 +1978,8 @@ static int smack_file_open(struct file *file, const struct cred *cred) */ static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp) { - struct task_smack *tsp; + struct task_smack *tsp = new_task_smack(NULL, NULL, gfp); - tsp = new_task_smack(NULL, NULL, gfp); if (tsp == NULL) return -ENOMEM; @@ -1985,7 +1996,7 @@ static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp) */ static void smack_cred_free(struct cred *cred) { - struct task_smack *tsp = cred->security; + struct task_smack *tsp = smack_cred(cred); struct smack_rule *rp; struct list_head *l; struct list_head *n; @@ -2015,7 +2026,7 @@ static void smack_cred_free(struct cred *cred) static int smack_cred_prepare(struct cred *new, const struct cred *old, gfp_t gfp) { - struct task_smack *old_tsp = old->security; + struct task_smack *old_tsp = smack_cred(old); struct task_smack *new_tsp; int rc; @@ -2045,8 +2056,8 @@ static int smack_cred_prepare(struct cred *new, const struct cred *old, */ static void smack_cred_transfer(struct cred *new, const struct cred *old) { - struct task_smack *old_tsp = old->security; - struct task_smack *new_tsp = new->security; + struct task_smack *old_tsp = smack_cred(old); + struct task_smack *new_tsp = smack_cred(new); new_tsp->smk_task = old_tsp->smk_task; new_tsp->smk_forked = old_tsp->smk_task; @@ -2066,7 +2077,7 @@ static void smack_cred_transfer(struct cred *new, const struct cred *old) */ static int smack_kernel_act_as(struct cred *new, u32 secid) { - struct task_smack *new_tsp = new->security; + struct task_smack *new_tsp = smack_cred(new); struct smack_known *skp = smack_from_secid(secid); if (skp == NULL) @@ -2088,7 +2099,7 @@ static int smack_kernel_create_files_as(struct cred *new, struct inode *inode) { struct inode_smack *isp = inode->i_security; - struct task_smack *tsp = new->security; + struct task_smack *tsp = smack_cred(new); tsp->smk_forked = isp->smk_inode; tsp->smk_task = tsp->smk_forked; @@ -3633,10 +3644,10 @@ static int smack_getprocattr(struct task_struct *p, char *name, char **value) * * Returns the length of the smack label or an error code */ -static int smack_setprocattr(struct task_struct *p, char *name, - void *value, size_t size) +static int smack_setprocattr(struct task_struct *p, char *name, void *value, + size_t size) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); struct cred *new; struct smack_known *skp; struct smack_known_list_elem *sklep; @@ -3683,7 +3694,7 @@ static int smack_setprocattr(struct task_struct *p, char *name, if (new == NULL) return -ENOMEM; - tsp = new->security; + tsp = smack_cred(new); tsp->smk_task = skp; /* * process can change its label only once @@ -4329,7 +4340,7 @@ static void smack_inet_csk_clone(struct sock *sk, static int smack_key_alloc(struct key *key, const struct cred *cred, unsigned long flags) { - struct smack_known *skp = smk_of_task(cred->security); + struct smack_known *skp = smk_of_task(smack_cred(cred)); key->security = skp; return 0; @@ -4360,7 +4371,7 @@ static int smack_key_permission(key_ref_t key_ref, { struct key *keyp; struct smk_audit_info ad; - struct smack_known *tkp = smk_of_task(cred->security); + struct smack_known *tkp = smk_of_task(smack_cred(cred)); int request = 0; int rc; @@ -4792,7 +4803,7 @@ static __init void init_smack_known_list(void) */ static __init int smack_init(void) { - struct cred *cred; + struct cred *cred = (struct cred *) current->cred; struct task_smack *tsp; if (!security_module_enable("smack")) @@ -4808,7 +4819,15 @@ static __init int smack_init(void) kmem_cache_destroy(smack_inode_cache); return -ENOMEM; } + /* + * Set the security state for the initial task. + */ + cred->security = tsp; + /* + * Register with LSM + */ + security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack"); smack_enabled = 1; pr_info("Smack: Initializing.\n"); @@ -4831,11 +4850,6 @@ static __init int smack_init(void) /* initialize the smack_known_list */ init_smack_known_list(); - /* - * Register with LSM - */ - security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack"); - return 0; } diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c index e249a66..6218bf7 100644 --- a/security/smack/smackfs.c +++ b/security/smack/smackfs.c @@ -2203,14 +2203,14 @@ static const struct file_operations smk_logging_ops = { static void *load_self_seq_start(struct seq_file *s, loff_t *pos) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); return smk_seq_start(s, pos, &tsp->smk_rules); } static void *load_self_seq_next(struct seq_file *s, void *v, loff_t *pos) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); return smk_seq_next(s, v, pos, &tsp->smk_rules); } @@ -2257,7 +2257,7 @@ static int smk_open_load_self(struct inode *inode, struct file *file) static ssize_t smk_write_load_self(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules, &tsp->smk_rules_lock, SMK_FIXED24_FMT); @@ -2409,14 +2409,14 @@ static const struct file_operations smk_load2_ops = { static void *load_self2_seq_start(struct seq_file *s, loff_t *pos) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); return smk_seq_start(s, pos, &tsp->smk_rules); } static void *load_self2_seq_next(struct seq_file *s, void *v, loff_t *pos) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); return smk_seq_next(s, v, pos, &tsp->smk_rules); } @@ -2462,7 +2462,7 @@ static int smk_open_load_self2(struct inode *inode, struct file *file) static ssize_t smk_write_load_self2(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); return smk_write_rules_list(file, buf, count, ppos, &tsp->smk_rules, &tsp->smk_rules_lock, SMK_LONG_FMT); @@ -2681,14 +2681,14 @@ static const struct file_operations smk_syslog_ops = { static void *relabel_self_seq_start(struct seq_file *s, loff_t *pos) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); return smk_seq_start(s, pos, &tsp->smk_relabel); } static void *relabel_self_seq_next(struct seq_file *s, void *v, loff_t *pos) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); return smk_seq_next(s, v, pos, &tsp->smk_relabel); } @@ -2736,7 +2736,7 @@ static int smk_open_relabel_self(struct inode *inode, struct file *file) static ssize_t smk_write_relabel_self(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { - struct task_smack *tsp = current_security(); + struct task_smack *tsp = smack_cred(current_cred()); char *data; int rc; LIST_HEAD(list_tmp);

[06/25] Smack: Abstract the cred security blob

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