return (atomic_read(&selinux_secmark_refcount) > 0);
}
-/* Allocate and free functions for each kind of security blob. */
-
-static int cred_alloc_security(struct cred *cred)
+/*
+ * initialise the security for the init task
+ */
+static void cred_init_security(void)
{
+ struct cred *cred = (struct cred *) current->cred;
struct task_security_struct *tsec;
tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
if (!tsec)
- return -ENOMEM;
+ panic("SELinux: Failed to initialize initial task.\n");
- tsec->osid = tsec->sid = SECINITSID_UNLABELED;
+ tsec->osid = tsec->sid = SECINITSID_KERNEL;
cred->security = tsec;
-
- return 0;
}
/*
return perm;
}
+/*
+ * Check permission between a pair of credentials
+ * fork check, ptrace check, etc.
+ */
+static int cred_has_perm(const struct cred *actor,
+ const struct cred *target,
+ u32 perms)
+{
+ u32 asid = cred_sid(actor), tsid = cred_sid(target);
+
+ return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
+}
+
/*
* Check permission between a pair of tasks, e.g. signal checks,
* fork check, ptrace check, etc.
return secondary_ops->capget(target, effective, inheritable, permitted);
}
-static int selinux_capset_check(const kernel_cap_t *effective,
- const kernel_cap_t *inheritable,
- const kernel_cap_t *permitted)
+static int selinux_capset(struct cred *new, const struct cred *old,
+ const kernel_cap_t *effective,
+ const kernel_cap_t *inheritable,
+ const kernel_cap_t *permitted)
{
int error;
- error = secondary_ops->capset_check(effective, inheritable, permitted);
+ error = secondary_ops->capset(new, old,
+ effective, inheritable, permitted);
if (error)
return error;
- return task_has_perm(current, current, PROCESS__SETCAP);
-}
-
-static void selinux_capset_set(const kernel_cap_t *effective,
- const kernel_cap_t *inheritable,
- const kernel_cap_t *permitted)
-{
- secondary_ops->capset_set(effective, inheritable, permitted);
+ return cred_has_perm(old, new, PROCESS__SETCAP);
}
static int selinux_capable(struct task_struct *tsk, int cap, int audit)
spin_unlock(&files->file_lock);
}
-static void selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
+static int selinux_bprm_apply_creds(struct linux_binprm *bprm, int unsafe)
{
struct task_security_struct *tsec;
struct bprm_security_struct *bsec;
+ struct cred *new;
u32 sid;
int rc;
- secondary_ops->bprm_apply_creds(bprm, unsafe);
+ rc = secondary_ops->bprm_apply_creds(bprm, unsafe);
+ if (rc < 0)
+ return rc;
- tsec = current_security();
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
+ tsec = new->security;
bsec = bprm->security;
sid = bsec->sid;
PROCESS__SHARE, NULL);
if (rc) {
bsec->unsafe = 1;
- return;
+ goto out;
}
}
PROCESS__PTRACE, NULL);
if (rc) {
bsec->unsafe = 1;
- return;
+ goto out;
}
}
}
tsec->sid = sid;
}
+
+out:
+ commit_creds(new);
+ return 0;
}
/*
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
const struct cred *cred = current_cred();
+ int rc = 0;
#ifndef CONFIG_PPC32
if ((prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
* private file mapping that will also be writable.
* This has an additional check.
*/
- int rc = task_has_perm(current, current, PROCESS__EXECMEM);
+ rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
if (rc)
- return rc;
+ goto error;
}
#endif
return file_has_perm(cred, file, av);
}
- return 0;
+
+error:
+ return rc;
}
static int selinux_file_mmap(struct file *file, unsigned long reqprot,
rc = 0;
if (vma->vm_start >= vma->vm_mm->start_brk &&
vma->vm_end <= vma->vm_mm->brk) {
- rc = task_has_perm(current, current,
- PROCESS__EXECHEAP);
+ rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
} else if (!vma->vm_file &&
vma->vm_start <= vma->vm_mm->start_stack &&
vma->vm_end >= vma->vm_mm->start_stack) {
* modified content. This typically should only
* occur for text relocations.
*/
- rc = file_has_perm(cred, vma->vm_file,
- FILE__EXECMOD);
+ rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
}
if (rc)
return rc;
struct file_security_struct *fsec;
struct inode *inode;
struct inode_security_struct *isec;
+
inode = file->f_path.dentry->d_inode;
fsec = file->f_security;
isec = inode->i_security;
return task_has_perm(current, current, PROCESS__FORK);
}
-static int selinux_cred_alloc_security(struct cred *cred)
+/*
+ * detach and free the LSM part of a set of credentials
+ */
+static void selinux_cred_free(struct cred *cred)
{
- struct task_security_struct *tsec1, *tsec2;
- int rc;
-
- tsec1 = current_security();
+ struct task_security_struct *tsec = cred->security;
+ cred->security = NULL;
+ kfree(tsec);
+}
- rc = cred_alloc_security(cred);
- if (rc)
- return rc;
- tsec2 = cred->security;
+/*
+ * prepare a new set of credentials for modification
+ */
+static int selinux_cred_prepare(struct cred *new, const struct cred *old,
+ gfp_t gfp)
+{
+ const struct task_security_struct *old_tsec;
+ struct task_security_struct *tsec;
- tsec2->osid = tsec1->osid;
- tsec2->sid = tsec1->sid;
+ old_tsec = old->security;
- /* Retain the exec, fs, key, and sock SIDs across fork */
- tsec2->exec_sid = tsec1->exec_sid;
- tsec2->create_sid = tsec1->create_sid;
- tsec2->keycreate_sid = tsec1->keycreate_sid;
- tsec2->sockcreate_sid = tsec1->sockcreate_sid;
+ tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
+ if (!tsec)
+ return -ENOMEM;
+ new->security = tsec;
return 0;
}
/*
- * detach and free the LSM part of a set of credentials
+ * commit new credentials
*/
-static void selinux_cred_free(struct cred *cred)
+static void selinux_cred_commit(struct cred *new, const struct cred *old)
{
- struct task_security_struct *tsec = cred->security;
- cred->security = NULL;
- kfree(tsec);
+ secondary_ops->cred_commit(new, old);
}
static int selinux_task_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
return 0;
}
-static int selinux_task_post_setuid(uid_t id0, uid_t id1, uid_t id2, int flags)
+static int selinux_task_fix_setuid(struct cred *new, const struct cred *old,
+ int flags)
{
- return secondary_ops->task_post_setuid(id0, id1, id2, flags);
+ return secondary_ops->task_fix_setuid(new, old, flags);
}
static int selinux_task_setgid(gid_t id0, gid_t id1, gid_t id2, int flags)
/* Control the ability to change the hard limit (whether
lowering or raising it), so that the hard limit can
later be used as a safe reset point for the soft limit
- upon context transitions. See selinux_bprm_apply_creds. */
+ upon context transitions. See selinux_bprm_committing_creds. */
if (old_rlim->rlim_max != new_rlim->rlim_max)
return task_has_perm(current, current, PROCESS__SETRLIMIT);
unsigned long arg2,
unsigned long arg3,
unsigned long arg4,
- unsigned long arg5,
- long *rc_p)
+ unsigned long arg5)
{
/* The current prctl operations do not appear to require
any SELinux controls since they merely observe or modify
the state of the current process. */
- return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5, rc_p);
+ return secondary_ops->task_prctl(option, arg2, arg3, arg4, arg5);
}
static int selinux_task_wait(struct task_struct *p)
return task_has_perm(p, current, PROCESS__SIGCHLD);
}
-static void selinux_task_reparent_to_init(struct task_struct *p)
-{
- struct task_security_struct *tsec;
-
- secondary_ops->task_reparent_to_init(p);
-
- tsec = p->cred->security;
- tsec->osid = tsec->sid;
- tsec->sid = SECINITSID_KERNEL;
- return;
-}
-
static void selinux_task_to_inode(struct task_struct *p,
struct inode *inode)
{
{
struct task_security_struct *tsec;
struct task_struct *tracer;
- u32 sid = 0;
+ struct cred *new;
+ u32 sid = 0, ptsid;
int error;
char *str = value;
return error;
}
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
/* Permission checking based on the specified context is
performed during the actual operation (execve,
open/mkdir/...), when we know the full context of the
- operation. See selinux_bprm_set_security for the execve
+ operation. See selinux_bprm_set_creds for the execve
checks and may_create for the file creation checks. The
operation will then fail if the context is not permitted. */
- tsec = p->cred->security;
- if (!strcmp(name, "exec"))
+ tsec = new->security;
+ if (!strcmp(name, "exec")) {
tsec->exec_sid = sid;
- else if (!strcmp(name, "fscreate"))
+ } else if (!strcmp(name, "fscreate")) {
tsec->create_sid = sid;
- else if (!strcmp(name, "keycreate")) {
+ } else if (!strcmp(name, "keycreate")) {
error = may_create_key(sid, p);
if (error)
- return error;
+ goto abort_change;
tsec->keycreate_sid = sid;
- } else if (!strcmp(name, "sockcreate"))
+ } else if (!strcmp(name, "sockcreate")) {
tsec->sockcreate_sid = sid;
- else if (!strcmp(name, "current")) {
- struct av_decision avd;
-
+ } else if (!strcmp(name, "current")) {
+ error = -EINVAL;
if (sid == 0)
- return -EINVAL;
- /*
- * SELinux allows to change context in the following case only.
- * - Single threaded processes.
- * - Multi threaded processes intend to change its context into
- * more restricted domain (defined by TYPEBOUNDS statement).
- */
- if (atomic_read(&p->mm->mm_users) != 1) {
- struct task_struct *g, *t;
- struct mm_struct *mm = p->mm;
- read_lock(&tasklist_lock);
- do_each_thread(g, t) {
- if (t->mm == mm && t != p) {
- read_unlock(&tasklist_lock);
- error = security_bounded_transition(tsec->sid, sid);
- if (!error)
- goto boundary_ok;
-
- return error;
- }
- } while_each_thread(g, t);
- read_unlock(&tasklist_lock);
+ goto abort_change;
+
+ /* Only allow single threaded processes to change context */
+ error = -EPERM;
+ if (!is_single_threaded(p)) {
+ error = security_bounded_transition(tsec->sid, sid);
+ if (error)
+ goto abort_change;
}
-boundary_ok:
/* Check permissions for the transition. */
error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
PROCESS__DYNTRANSITION, NULL);
if (error)
- return error;
+ goto abort_change;
/* Check for ptracing, and update the task SID if ok.
Otherwise, leave SID unchanged and fail. */
+ ptsid = 0;
task_lock(p);
- rcu_read_lock();
tracer = tracehook_tracer_task(p);
- if (tracer != NULL) {
- u32 ptsid = task_sid(tracer);
- rcu_read_unlock();
- error = avc_has_perm_noaudit(ptsid, sid,
- SECCLASS_PROCESS,
- PROCESS__PTRACE, 0, &avd);
- if (!error)
- tsec->sid = sid;
- task_unlock(p);
- avc_audit(ptsid, sid, SECCLASS_PROCESS,
- PROCESS__PTRACE, &avd, error, NULL);
+ if (tracer)
+ ptsid = task_sid(tracer);
+ task_unlock(p);
+
+ if (tracer) {
+ error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
+ PROCESS__PTRACE, NULL);
if (error)
- return error;
- } else {
- rcu_read_unlock();
- tsec->sid = sid;
- task_unlock(p);
+ goto abort_change;
}
- } else
- return -EINVAL;
+ tsec->sid = sid;
+ } else {
+ error = -EINVAL;
+ goto abort_change;
+ }
+
+ commit_creds(new);
return size;
+
+abort_change:
+ abort_creds(new);
+ return error;
}
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
#ifdef CONFIG_KEYS
-static int selinux_key_alloc(struct key *k, struct task_struct *tsk,
+static int selinux_key_alloc(struct key *k, const struct cred *cred,
unsigned long flags)
{
- const struct task_security_struct *__tsec;
+ const struct task_security_struct *tsec;
struct key_security_struct *ksec;
ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
if (!ksec)
return -ENOMEM;
- rcu_read_lock();
- __tsec = __task_cred(tsk)->security;
- if (__tsec->keycreate_sid)
- ksec->sid = __tsec->keycreate_sid;
+ tsec = cred->security;
+ if (tsec->keycreate_sid)
+ ksec->sid = tsec->keycreate_sid;
else
- ksec->sid = __tsec->sid;
- rcu_read_unlock();
+ ksec->sid = tsec->sid;
k->security = ksec;
return 0;
}
static int selinux_key_permission(key_ref_t key_ref,
- struct task_struct *ctx,
- key_perm_t perm)
+ const struct cred *cred,
+ key_perm_t perm)
{
struct key *key;
struct key_security_struct *ksec;
if (perm == 0)
return 0;
- sid = task_sid(ctx);
+ sid = cred_sid(cred);
key = key_ref_to_ptr(key_ref);
ksec = key->security;
.ptrace_may_access = selinux_ptrace_may_access,
.ptrace_traceme = selinux_ptrace_traceme,
.capget = selinux_capget,
- .capset_check = selinux_capset_check,
- .capset_set = selinux_capset_set,
+ .capset = selinux_capset,
.sysctl = selinux_sysctl,
.capable = selinux_capable,
.quotactl = selinux_quotactl,
.dentry_open = selinux_dentry_open,
.task_create = selinux_task_create,
- .cred_alloc_security = selinux_cred_alloc_security,
.cred_free = selinux_cred_free,
+ .cred_prepare = selinux_cred_prepare,
+ .cred_commit = selinux_cred_commit,
.task_setuid = selinux_task_setuid,
- .task_post_setuid = selinux_task_post_setuid,
+ .task_fix_setuid = selinux_task_fix_setuid,
.task_setgid = selinux_task_setgid,
.task_setpgid = selinux_task_setpgid,
.task_getpgid = selinux_task_getpgid,
.task_kill = selinux_task_kill,
.task_wait = selinux_task_wait,
.task_prctl = selinux_task_prctl,
- .task_reparent_to_init = selinux_task_reparent_to_init,
.task_to_inode = selinux_task_to_inode,
.ipc_permission = selinux_ipc_permission,
static __init int selinux_init(void)
{
- struct task_security_struct *tsec;
-
if (!security_module_enable(&selinux_ops)) {
selinux_enabled = 0;
return 0;
printk(KERN_INFO "SELinux: Initializing.\n");
/* Set the security state for the initial task. */
- if (cred_alloc_security(current->cred))
- panic("SELinux: Failed to initialize initial task.\n");
- tsec = current->cred->security;
- tsec->osid = tsec->sid = SECINITSID_KERNEL;
+ cred_init_security();
sel_inode_cache = kmem_cache_create("selinux_inode_security",
sizeof(struct inode_security_struct),
projects / linux-2.6-omap-h63xx.git / blobdiff