Exemple #1
0
/* Set the cred info into the current task */
void
crset(cred_t * cr)
{
#if defined(STRUCT_TASK_STRUCT_HAS_CRED)
    struct cred *new_creds;

    /* If our current task doesn't have identical real and effective
     * credentials, commit_cred won't let us change them, so we just
     * bail here.
     */
    if (current->cred != current->real_cred)
        return;
    new_creds = prepare_creds();
    /* Drop the reference to group_info - we'll overwrite it in afs_copy_creds */
    put_group_info(new_creds->group_info);
    afs_copy_creds(new_creds, current_cred());

    commit_creds(new_creds);
#else
    struct group_info *old_info;

    current->fsuid = afs_cr_uid(cr);
    current->uid = afs_cr_ruid(cr);
    current->fsgid = afs_cr_gid(cr);
    current->gid = afs_cr_rgid(cr);

    get_group_info(afs_cr_group_info(cr));
    task_lock(current);
    old_info = current->group_info;
    current->group_info = afs_cr_group_info(cr);
    task_unlock(current);
    put_group_info(old_info);
#endif
}
Exemple #2
0
asmlinkage long sys_getgroups(int gidsetsize, gid_t __user *grouplist)
{
	int i = 0;

	/*
	 *	SMP: Nobody else can change our grouplist. Thus we are
	 *	safe.
	 */

	if (gidsetsize < 0)
		return -EINVAL;

	/* no need to grab task_lock here; it cannot change */
	get_group_info(current->group_info);
	i = current->group_info->ngroups;
	if (gidsetsize) {
		if (i > gidsetsize) {
			i = -EINVAL;
			goto out;
		}
		if (groups_to_user(grouplist, current->group_info)) {
			i = -EFAULT;
			goto out;
		}
	}
out:
	put_group_info(current->group_info);
	return i;
}
Exemple #3
0
int in_egroup_p(gid_t grp)
{
	int retval = 1;
	if (grp != current->egid) {
		get_group_info(current->group_info);
		retval = groups_search(current->group_info, grp);
		put_group_info(current->group_info);
	}
	return retval;
}
Exemple #4
0
/*
 * Return an array of supplemental gids.  The returned address is safe
 * to use as long as the caller has taken a reference with crhold().
 * The caller is responsible for releasing the reference with crfree().
 */
gid_t *
crgetgroups(const cred_t *cr)
{
	struct group_info *gi;
	gid_t *gids;

	gi = get_group_info(cr->group_info);
	gids = gi->blocks[0];
	put_group_info(gi);

	return gids;
}
Exemple #5
0
void
crfree(cred_t * cr)
{
#if defined(STRUCT_TASK_STRUCT_HAS_CRED)
    put_cred(cr);
#else
    if (atomic_dec_and_test(&cr->cr_ref)) {
        put_group_info(afs_cr_group_info(cr));
        kfree(cr);
    }
#endif
}
Exemple #6
0
/* Check if the passed gid is available is in supplied credential. */
int
groupmember(gid_t gid, const cred_t *cr)
{
	struct group_info *gi;
	int rc;

	gi = get_group_info(cr->group_info);
	rc = cr_groups_search(cr->group_info, gid);
	put_group_info(gi);

	return rc;
}
Exemple #7
0
/* Return the number of supplemental groups */
int
crgetngroups(const cred_t *cr)
{
	struct group_info *gi;
	int rc;

	gi = get_group_info(cr->group_info);
	rc = gi->ngroups;
	put_group_info(gi);

	return rc;
}
Exemple #8
0
void __put_task_struct(struct task_struct *tsk)
{
	WARN_ON(!(tsk->state & (TASK_DEAD | TASK_ZOMBIE)));
	WARN_ON(atomic_read(&tsk->usage));
	WARN_ON(tsk == current);

	if (unlikely(tsk->audit_context))
		audit_free(tsk);
	security_task_free(tsk);
	free_uid(tsk->user);
	put_group_info(tsk->group_info);
	free_task(tsk);
}
Exemple #9
0
static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
				struct pid *pid, struct task_struct *p)
{
	struct group_info *group_info;
	int g;
	struct fdtable *fdt = NULL;
	pid_t ppid, tpid;

	rcu_read_lock();
	ppid = pid_alive(p) ?
		task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
	tpid = 0;
	if (pid_alive(p)) {
		struct task_struct *tracer = tracehook_tracer_task(p);
		if (tracer)
			tpid = task_pid_nr_ns(tracer, ns);
	}
	seq_printf(m,
		"State:\t%s\n"
		"Tgid:\t%d\n"
		"Pid:\t%d\n"
		"PPid:\t%d\n"
		"TracerPid:\t%d\n"
		"Uid:\t%d\t%d\t%d\t%d\n"
		"Gid:\t%d\t%d\t%d\t%d\n",
		get_task_state(p),
		task_tgid_nr_ns(p, ns),
		pid_nr_ns(pid, ns),
		ppid, tpid,
		p->uid, p->euid, p->suid, p->fsuid,
		p->gid, p->egid, p->sgid, p->fsgid);

	task_lock(p);
	if (p->files)
		fdt = files_fdtable(p->files);
	seq_printf(m,
		"FDSize:\t%d\n"
		"Groups:\t",
		fdt ? fdt->max_fds : 0);
	rcu_read_unlock();

	group_info = p->group_info;
	get_group_info(group_info);
	task_unlock(p);

	for (g = 0; g < min(group_info->ngroups, NGROUPS_SMALL); g++)
		seq_printf(m, "%d ", GROUP_AT(group_info, g));
	put_group_info(group_info);

	seq_printf(m, "\n");
}
Exemple #10
0
void
crfree(cred_t * cr)
{
    if (cr->cr_ref > 1) {
	cr->cr_ref--;
	return;
    }

#if defined(AFS_LINUX26_ENV)
    put_group_info(cr->cr_group_info);
#endif

    kfree(cr);
}
Exemple #11
0
void __put_task_struct(struct task_struct *tsk)
{
	WARN_ON(!tsk->exit_state);
	WARN_ON(atomic_read(&tsk->usage));
	WARN_ON(tsk == current);

	security_task_free(tsk);
	free_uid(tsk->user);
	put_group_info(tsk->group_info);
	delayacct_tsk_free(tsk);

	if (!profile_handoff_task(tsk))
		free_task(tsk);
}
Exemple #12
0
SYSCALL_DEFINE2(setgroups16, int, gidsetsize, old_gid_t __user *, grouplist)
{
	struct group_info *group_info;
	int retval;

	if (!nsown_capable(CAP_SETGID))
		return -EPERM;
	if ((unsigned)gidsetsize > NGROUPS_MAX)
		return -EINVAL;

	group_info = groups_alloc(gidsetsize);
	if (!group_info)
		return -ENOMEM;
	retval = groups16_from_user(group_info, grouplist);
	if (retval) {
		put_group_info(group_info);
		return retval;
	}

	retval = set_current_groups(group_info);
	put_group_info(group_info);

	return retval;
}
Exemple #13
0
void __put_task_struct(struct task_struct *tsk)
{
	WARN_ON(!(tsk->exit_state & (EXIT_DEAD | EXIT_ZOMBIE)));
	WARN_ON(atomic_read(&tsk->usage));
	WARN_ON(tsk == current);

	if (unlikely(tsk->audit_context))
		audit_free(tsk);
	security_task_free(tsk);
	free_uid(tsk->user);
	put_group_info(tsk->group_info);

	if (!profile_handoff_task(tsk))
		free_task(tsk);
}
Exemple #14
0
asmlinkage long sys_setgroups16(int gidsetsize, old_gid_t __user *grouplist)
{
    struct group_info *group_info;
    int retval;

    if (!capable(CAP_SETGID))
        return -EPERM;
    if ((unsigned)gidsetsize > NGROUPS_MAX)
        return -EINVAL;

    group_info = groups_alloc(gidsetsize);
    if (!group_info)
        return -ENOMEM;
    retval = groups16_from_user(group_info, grouplist);
    if (retval) {
        put_group_info(group_info);
        return retval;
    }

    retval = set_current_groups(group_info);
    put_group_info(group_info);

    return retval;
}
Exemple #15
0
static void mdt_identity_entry_free(struct upcall_cache *cache,
				    struct upcall_cache_entry *entry)
{
	struct md_identity *identity = &entry->u.identity;

	if (identity->mi_ginfo) {
		put_group_info(identity->mi_ginfo);
		identity->mi_ginfo = NULL;
	}

	if (identity->mi_nperms) {
		LASSERT(identity->mi_perms);
		OBD_FREE(identity->mi_perms,
			 identity->mi_nperms * sizeof(struct md_perm));
		identity->mi_nperms = 0;
	}
}
static inline char * task_state(struct task_struct *p, char *buffer)
{
	struct group_info *group_info;
	int g;
	struct fdtable *fdt = NULL;

	read_lock(&tasklist_lock);
	buffer += sprintf(buffer,
		"State:\t%s\n"
		"SleepAVG:\t%lu%%\n"
		"Tgid:\t%d\n"
		"Pid:\t%d\n"
		"PPid:\t%d\n"
		"TracerPid:\t%d\n"
		"Uid:\t%d\t%d\t%d\t%d\n"
		"Gid:\t%d\t%d\t%d\t%d\n",
		get_task_state(p),
		(p->sleep_avg/1024)*100/(1020000000/1024),
	       	p->tgid,
		p->pid, pid_alive(p) ? p->group_leader->real_parent->tgid : 0,
		pid_alive(p) && p->ptrace ? p->parent->pid : 0,
		p->uid, p->euid, p->suid, p->fsuid,
		p->gid, p->egid, p->sgid, p->fsgid);
	read_unlock(&tasklist_lock);
	task_lock(p);
	rcu_read_lock();
	if (p->files)
		fdt = files_fdtable(p->files);
	buffer += sprintf(buffer,
		"FDSize:\t%d\n"
		"Groups:\t",
		fdt ? fdt->max_fds : 0);
	rcu_read_unlock();

	group_info = p->group_info;
	get_group_info(group_info);
	task_unlock(p);

	for (g = 0; g < min(group_info->ngroups,NGROUPS_SMALL); g++)
		buffer += sprintf(buffer, "%d ", GROUP_AT(group_info,g));
	put_group_info(group_info);

	buffer += sprintf(buffer, "\n");
	return buffer;
}
Exemple #17
0
/* Check if the passed gid is available is in supplied credential. */
int
groupmember(gid_t gid, const cred_t *cr)
{
	int lock, rc;

	lock = (cr != current);
	if (lock)
		task_lock((struct task_struct *)cr);

	get_group_info(cr->group_info);
	rc = cr_groups_search(cr->group_info, gid);
	put_group_info(cr->group_info);

	if (lock)
		task_unlock((struct task_struct *)cr);

	return rc;
}
Exemple #18
0
/*
 * Use the SETCLIENTID credential
 */
static struct rpc_cred *
nfsd4_lookupcred(struct nfs4_client *clp, int taskflags)
{
        struct auth_cred acred;
	struct rpc_clnt *clnt = clp->cl_callback.cb_client;
	struct rpc_cred *ret;

        get_group_info(clp->cl_cred.cr_group_info);
        acred.uid = clp->cl_cred.cr_uid;
        acred.gid = clp->cl_cred.cr_gid;
        acred.group_info = clp->cl_cred.cr_group_info;

        dprintk("NFSD:     looking up %s cred\n",
                clnt->cl_auth->au_ops->au_name);
        ret = rpcauth_lookup_credcache(clnt->cl_auth, &acred, taskflags);
        put_group_info(clp->cl_cred.cr_group_info);
        return ret;
}
Exemple #19
0
/* Return the number of supplemental groups */
int
crgetngroups(const cred_t *cr)
{
	int lock, rc;

	lock = (cr != current);
	if (lock)
		task_lock((struct task_struct *)cr);

	get_group_info(cr->group_info);
	rc = cr->group_info->ngroups;
	put_group_info(cr->group_info);

	if (lock)
		task_unlock((struct task_struct *)cr);

	return rc;
}
Exemple #20
0
static inline void task_state(struct seq_file *m, struct pid *pid,
				struct task_struct *p)
{
	struct group_info *group_info;
	int g;
	struct fdtable *fdt = NULL;

	rcu_read_lock();
	seq_printf(m,
		"State:\t%s\n"
		"SleepAVG:\t%lu%%\n"
		"Tgid:\t%d\n"
		"Pid:\t%d\n"
		"PPid:\t%d\n"
		"TracerPid:\t%d\n"
		"Uid:\t%d\t%d\t%d\t%d\n"
		"Gid:\t%d\t%d\t%d\t%d\n",
		get_task_state(p),
		(p->sleep_avg/1024)*100/(1020000000/1024),
	       	p->tgid, p->pid,
	       	pid_alive(p) ? rcu_dereference(p->real_parent)->tgid : 0,
		pid_alive(p) && p->ptrace ? rcu_dereference(p->parent)->pid : 0,
		p->uid, p->euid, p->suid, p->fsuid,
		p->gid, p->egid, p->sgid, p->fsgid);

	task_lock(p);
	if (p->files)
		fdt = files_fdtable(p->files);
	seq_printf(m,
		"FDSize:\t%d\n"
		"Groups:\t",
		fdt ? fdt->max_fds : 0);
	rcu_read_unlock();

	group_info = p->group_info;
	get_group_info(group_info);
	task_unlock(p);

	for (g = 0; g < min(group_info->ngroups, NGROUPS_SMALL); g++)
		seq_printf(m, "%d ", GROUP_AT(group_info, g));
	put_group_info(group_info);

	seq_printf(m, "\n");
}
Exemple #21
0
/*
 * Return an array of supplemental gids.  The returned address is safe
 * to use as long as the caller has taken a reference with crhold().
 * The caller is responsible for releasing the reference with crfree().
 */
gid_t *
crgetgroups(const cred_t *cr)
{
	gid_t *gids;
	int lock;

	lock = (cr != current);
	if (lock)
		task_lock((struct task_struct *)cr);

	get_group_info(cr->group_info);
	gids = cr->group_info->blocks[0];
	put_group_info(cr->group_info);

	if (lock)
		task_unlock((struct task_struct *)cr);

	return gids;
}
Exemple #22
0
/* Set the cred info into the current task */
void
crset(cred_t * cr)
{
#if defined(STRUCT_TASK_HAS_CRED)
    struct cred *new_creds;

    new_creds = prepare_creds();
    new_creds->fsuid = cr->cr_uid;
    new_creds->uid = cr->cr_ruid;
    new_creds->fsgid = cr->cr_gid;
    new_creds->gid = cr->cr_rgid;
#else
    current->fsuid = cr->cr_uid;
    current->uid = cr->cr_ruid;
    current->fsgid = cr->cr_gid;
    current->gid = cr->cr_rgid;
#endif
#if defined(AFS_LINUX26_ENV)
{
    struct group_info *old_info;

    /* using set_current_groups() will sort the groups */
    get_group_info(cr->cr_group_info);

    task_lock(current);
#if defined(STRUCT_TASK_HAS_CRED)
    old_info = current->cred->group_info;
    new_creds->group_info = cr->cr_group_info;
    commit_creds(new_creds);
#else
    old_info = current->group_info;
    current->group_info = cr->cr_group_info;
#endif
    task_unlock(current);

    put_group_info(old_info);
}
#else
    memcpy(current->groups, cr->cr_groups, NGROUPS * sizeof(gid_t));
    current->ngroups = cr->cr_ngroups;
#endif
}
Exemple #23
0
void mdt_exit_ucred(struct mdt_thread_info *info)
{
	struct lu_ucred   *uc  = mdt_ucred(info);
	struct mdt_device *mdt = info->mti_mdt;

	LASSERT(uc != NULL);
	if (uc->uc_valid != UCRED_INIT) {
		uc->uc_suppgids[0] = uc->uc_suppgids[1] = -1;
		if (uc->uc_ginfo) {
			put_group_info(uc->uc_ginfo);
			uc->uc_ginfo = NULL;
		}
		if (uc->uc_identity) {
			mdt_identity_put(mdt->mdt_identity_cache,
					 uc->uc_identity);
			uc->uc_identity = NULL;
		}
		uc->uc_valid = UCRED_INIT;
	}
}
Exemple #24
0
/* validate and set current->group_info */
int set_current_groups(struct group_info *group_info)
{
	int retval;
	struct group_info *old_info;

	retval = security_task_setgroups(group_info);
	if (retval)
		return retval;

	groups_sort(group_info);
	get_group_info(group_info);

	task_lock(current);
	old_info = current->group_info;
	current->group_info = group_info;
	task_unlock(current);

	put_group_info(old_info);

	return 0;
}
Exemple #25
0
asmlinkage long sys_getgroups16(int gidsetsize, old_gid_t __user *grouplist)
{
    int i = 0;

    if (gidsetsize < 0)
        return -EINVAL;

    get_group_info(current->group_info);
    i = current->group_info->ngroups;
    if (gidsetsize) {
        if (i > gidsetsize) {
            i = -EINVAL;
            goto out;
        }
        if (groups16_to_user(grouplist, current->group_info)) {
            i = -EFAULT;
            goto out;
        }
    }
out:
    put_group_info(current->group_info);
    return i;
}
Exemple #26
0
/*
 * This creates a new process as a copy of the old one,
 * but does not actually start it yet.
 *
 * It copies the registers, and all the appropriate
 * parts of the process environment (as per the clone
 * flags). The actual kick-off is left to the caller.
 */
static task_t *copy_process(unsigned long clone_flags,
				 unsigned long stack_start,
				 struct pt_regs *regs,
				 unsigned long stack_size,
				 int __user *parent_tidptr,
				 int __user *child_tidptr,
				 int pid)
{
	int retval;
	struct task_struct *p = NULL;

	if ((clone_flags & (CLONE_NEWNS|CLONE_FS)) == (CLONE_NEWNS|CLONE_FS))
		return ERR_PTR(-EINVAL);

	/*
	 * Thread groups must share signals as well, and detached threads
	 * can only be started up within the thread group.
	 */
	if ((clone_flags & CLONE_THREAD) && !(clone_flags & CLONE_SIGHAND))
		return ERR_PTR(-EINVAL);

	/*
	 * Shared signal handlers imply shared VM. By way of the above,
	 * thread groups also imply shared VM. Blocking this case allows
	 * for various simplifications in other code.
	 */
	if ((clone_flags & CLONE_SIGHAND) && !(clone_flags & CLONE_VM))
		return ERR_PTR(-EINVAL);

	retval = security_task_create(clone_flags);
	if (retval)
		goto fork_out;

	retval = -ENOMEM;
	p = dup_task_struct(current);
	if (!p)
		goto fork_out;

	retval = -EAGAIN;
	if (atomic_read(&p->user->processes) >=
			p->signal->rlim[RLIMIT_NPROC].rlim_cur) {
		if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_RESOURCE) &&
				p->user != &root_user)
			goto bad_fork_free;
	}

	atomic_inc(&p->user->__count);
	atomic_inc(&p->user->processes);
	get_group_info(p->group_info);

	/*
	 * If multiple threads are within copy_process(), then this check
	 * triggers too late. This doesn't hurt, the check is only there
	 * to stop root fork bombs.
	 */
	if (nr_threads >= max_threads)
		goto bad_fork_cleanup_count;

	if (!try_module_get(p->thread_info->exec_domain->module))
		goto bad_fork_cleanup_count;

	if (p->binfmt && !try_module_get(p->binfmt->module))
		goto bad_fork_cleanup_put_domain;

	p->did_exec = 0;
	copy_flags(clone_flags, p);
	p->pid = pid;
	retval = -EFAULT;
	if (clone_flags & CLONE_PARENT_SETTID)
		if (put_user(p->pid, parent_tidptr))
			goto bad_fork_cleanup;

	p->proc_dentry = NULL;

	INIT_LIST_HEAD(&p->children);
	INIT_LIST_HEAD(&p->sibling);
	p->vfork_done = NULL;
	spin_lock_init(&p->alloc_lock);
	spin_lock_init(&p->proc_lock);

	clear_tsk_thread_flag(p, TIF_SIGPENDING);
	init_sigpending(&p->pending);

	p->it_real_value = 0;
	p->it_real_incr = 0;
	p->it_virt_value = cputime_zero;
	p->it_virt_incr = cputime_zero;
	p->it_prof_value = cputime_zero;
	p->it_prof_incr = cputime_zero;
	init_timer(&p->real_timer);
	p->real_timer.data = (unsigned long) p;

	p->utime = cputime_zero;
	p->stime = cputime_zero;
	p->rchar = 0;		/* I/O counter: bytes read */
	p->wchar = 0;		/* I/O counter: bytes written */
	p->syscr = 0;		/* I/O counter: read syscalls */
	p->syscw = 0;		/* I/O counter: write syscalls */
	acct_clear_integrals(p);

	p->lock_depth = -1;		/* -1 = no lock */
	do_posix_clock_monotonic_gettime(&p->start_time);
	p->security = NULL;
	p->io_context = NULL;
	p->io_wait = NULL;
	p->audit_context = NULL;
#ifdef CONFIG_NUMA
 	p->mempolicy = mpol_copy(p->mempolicy);
 	if (IS_ERR(p->mempolicy)) {
 		retval = PTR_ERR(p->mempolicy);
 		p->mempolicy = NULL;
 		goto bad_fork_cleanup;
 	}
#endif

	p->tgid = p->pid;
	if (clone_flags & CLONE_THREAD)
		p->tgid = current->tgid;

	if ((retval = security_task_alloc(p)))
		goto bad_fork_cleanup_policy;
	if ((retval = audit_alloc(p)))
		goto bad_fork_cleanup_security;
	/* copy all the process information */
	if ((retval = copy_semundo(clone_flags, p)))
		goto bad_fork_cleanup_audit;
	if ((retval = copy_files(clone_flags, p)))
		goto bad_fork_cleanup_semundo;
	if ((retval = copy_fs(clone_flags, p)))
		goto bad_fork_cleanup_files;
	if ((retval = copy_sighand(clone_flags, p)))
		goto bad_fork_cleanup_fs;
	if ((retval = copy_signal(clone_flags, p)))
		goto bad_fork_cleanup_sighand;
	if ((retval = copy_mm(clone_flags, p)))
		goto bad_fork_cleanup_signal;
	if ((retval = copy_keys(clone_flags, p)))
		goto bad_fork_cleanup_mm;
	if ((retval = copy_namespace(clone_flags, p)))
		goto bad_fork_cleanup_keys;
	retval = copy_thread(0, clone_flags, stack_start, stack_size, p, regs);
	if (retval)
		goto bad_fork_cleanup_namespace;

	p->set_child_tid = (clone_flags & CLONE_CHILD_SETTID) ? child_tidptr : NULL;
	/*
	 * Clear TID on mm_release()?
	 */
	p->clear_child_tid = (clone_flags & CLONE_CHILD_CLEARTID) ? child_tidptr: NULL;

	/*
	 * Syscall tracing should be turned off in the child regardless
	 * of CLONE_PTRACE.
	 */
	clear_tsk_thread_flag(p, TIF_SYSCALL_TRACE);

	/* Our parent execution domain becomes current domain
	   These must match for thread signalling to apply */
	   
	p->parent_exec_id = p->self_exec_id;

	/* ok, now we should be set up.. */
	p->exit_signal = (clone_flags & CLONE_THREAD) ? -1 : (clone_flags & CSIGNAL);
	p->pdeath_signal = 0;
	p->exit_state = 0;

	/* Perform scheduler related setup */
	sched_fork(p);

	/*
	 * Ok, make it visible to the rest of the system.
	 * We dont wake it up yet.
	 */
	p->group_leader = p;
	INIT_LIST_HEAD(&p->ptrace_children);
	INIT_LIST_HEAD(&p->ptrace_list);

	/* Need tasklist lock for parent etc handling! */
	write_lock_irq(&tasklist_lock);

	/*
	 * The task hasn't been attached yet, so cpus_allowed mask cannot
	 * have changed. The cpus_allowed mask of the parent may have
	 * changed after it was copied first time, and it may then move to
	 * another CPU - so we re-copy it here and set the child's CPU to
	 * the parent's CPU. This avoids alot of nasty races.
	 */
	p->cpus_allowed = current->cpus_allowed;
	set_task_cpu(p, smp_processor_id());

	/*
	 * Check for pending SIGKILL! The new thread should not be allowed
	 * to slip out of an OOM kill. (or normal SIGKILL.)
	 */
	if (sigismember(&current->pending.signal, SIGKILL)) {
		write_unlock_irq(&tasklist_lock);
		retval = -EINTR;
		goto bad_fork_cleanup_namespace;
	}

	/* CLONE_PARENT re-uses the old parent */
	if (clone_flags & (CLONE_PARENT|CLONE_THREAD))
		p->real_parent = current->real_parent;
	else
		p->real_parent = current;
	p->parent = p->real_parent;

	if (clone_flags & CLONE_THREAD) {
		spin_lock(&current->sighand->siglock);
		/*
		 * Important: if an exit-all has been started then
		 * do not create this new thread - the whole thread
		 * group is supposed to exit anyway.
		 */
		if (current->signal->flags & SIGNAL_GROUP_EXIT) {
			spin_unlock(&current->sighand->siglock);
			write_unlock_irq(&tasklist_lock);
			retval = -EAGAIN;
			goto bad_fork_cleanup_namespace;
		}
		p->group_leader = current->group_leader;

		if (current->signal->group_stop_count > 0) {
			/*
			 * There is an all-stop in progress for the group.
			 * We ourselves will stop as soon as we check signals.
			 * Make the new thread part of that group stop too.
			 */
			current->signal->group_stop_count++;
			set_tsk_thread_flag(p, TIF_SIGPENDING);
		}

		spin_unlock(&current->sighand->siglock);
	}

	SET_LINKS(p);
	if (unlikely(p->ptrace & PT_PTRACED))
		__ptrace_link(p, current->parent);

	attach_pid(p, PIDTYPE_PID, p->pid);
	attach_pid(p, PIDTYPE_TGID, p->tgid);
	if (thread_group_leader(p)) {
		attach_pid(p, PIDTYPE_PGID, process_group(p));
		attach_pid(p, PIDTYPE_SID, p->signal->session);
		if (p->pid)
			__get_cpu_var(process_counts)++;
	}

	nr_threads++;
	total_forks++;
	write_unlock_irq(&tasklist_lock);
	retval = 0;

fork_out:
	if (retval)
		return ERR_PTR(retval);
	return p;

bad_fork_cleanup_namespace:
	exit_namespace(p);
bad_fork_cleanup_keys:
	exit_keys(p);
bad_fork_cleanup_mm:
	if (p->mm)
		mmput(p->mm);
bad_fork_cleanup_signal:
	exit_signal(p);
bad_fork_cleanup_sighand:
	exit_sighand(p);
bad_fork_cleanup_fs:
	exit_fs(p); /* blocking */
bad_fork_cleanup_files:
	exit_files(p); /* blocking */
bad_fork_cleanup_semundo:
	exit_sem(p);
bad_fork_cleanup_audit:
	audit_free(p);
bad_fork_cleanup_security:
	security_task_free(p);
bad_fork_cleanup_policy:
#ifdef CONFIG_NUMA
	mpol_free(p->mempolicy);
#endif
bad_fork_cleanup:
	if (p->binfmt)
		module_put(p->binfmt->module);
bad_fork_cleanup_put_domain:
	module_put(p->thread_info->exec_domain->module);
bad_fork_cleanup_count:
	put_group_info(p->group_info);
	atomic_dec(&p->user->processes);
	free_uid(p->user);
bad_fork_free:
	free_task(p);
	goto fork_out;
}
Exemple #27
0
/*
 * This creates a new process as a copy of the old one,
 * but does not actually start it yet.
 *
 * It copies the registers, and all the appropriate
 * parts of the process environment (as per the clone
 * flags). The actual kick-off is left to the caller.
 */
static struct task_struct *copy_process(unsigned long clone_flags,
					unsigned long stack_start,
					struct pt_regs *regs,
					unsigned long stack_size,
					int __user *child_tidptr,
					struct pid *pid,
					int trace)
{
	int retval;
	struct task_struct *p;
	int cgroup_callbacks_done = 0;

	if ((clone_flags & (CLONE_NEWNS|CLONE_FS)) == (CLONE_NEWNS|CLONE_FS))
		return ERR_PTR(-EINVAL);

	/*
	 * Thread groups must share signals as well, and detached threads
	 * can only be started up within the thread group.
	 */
	if ((clone_flags & CLONE_THREAD) && !(clone_flags & CLONE_SIGHAND))
		return ERR_PTR(-EINVAL);

	/*
	 * Shared signal handlers imply shared VM. By way of the above,
	 * thread groups also imply shared VM. Blocking this case allows
	 * for various simplifications in other code.
	 */
	if ((clone_flags & CLONE_SIGHAND) && !(clone_flags & CLONE_VM))
		return ERR_PTR(-EINVAL);

	retval = security_task_create(clone_flags);
	if (retval)
		goto fork_out;

	retval = -ENOMEM;
	p = dup_task_struct(current);
	if (!p)
		goto fork_out;

	rt_mutex_init_task(p);

#ifdef CONFIG_PROVE_LOCKING
	DEBUG_LOCKS_WARN_ON(!p->hardirqs_enabled);
	DEBUG_LOCKS_WARN_ON(!p->softirqs_enabled);
#endif
	retval = -EAGAIN;
	if (atomic_read(&p->user->processes) >=
			p->signal->rlim[RLIMIT_NPROC].rlim_cur) {
		if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_RESOURCE) &&
		    p->user != current->nsproxy->user_ns->root_user)
			goto bad_fork_free;
	}

	atomic_inc(&p->user->__count);
	atomic_inc(&p->user->processes);
	get_group_info(p->group_info);

	/*
	 * If multiple threads are within copy_process(), then this check
	 * triggers too late. This doesn't hurt, the check is only there
	 * to stop root fork bombs.
	 */
	if (nr_threads >= max_threads)
		goto bad_fork_cleanup_count;

	if (!try_module_get(task_thread_info(p)->exec_domain->module))
		goto bad_fork_cleanup_count;

	if (p->binfmt && !try_module_get(p->binfmt->module))
		goto bad_fork_cleanup_put_domain;

	p->did_exec = 0;
	delayacct_tsk_init(p);	/* Must remain after dup_task_struct() */
	copy_flags(clone_flags, p);
	INIT_LIST_HEAD(&p->children);
	INIT_LIST_HEAD(&p->sibling);
#ifdef CONFIG_PREEMPT_RCU
	p->rcu_read_lock_nesting = 0;
	p->rcu_flipctr_idx = 0;
#endif /* #ifdef CONFIG_PREEMPT_RCU */
	p->vfork_done = NULL;
	spin_lock_init(&p->alloc_lock);

	clear_tsk_thread_flag(p, TIF_SIGPENDING);
	init_sigpending(&p->pending);

	p->utime = cputime_zero;
	p->stime = cputime_zero;
	p->gtime = cputime_zero;
	p->utimescaled = cputime_zero;
	p->stimescaled = cputime_zero;
	p->prev_utime = cputime_zero;
	p->prev_stime = cputime_zero;

#ifdef CONFIG_DETECT_SOFTLOCKUP
	p->last_switch_count = 0;
	p->last_switch_timestamp = 0;
#endif

	task_io_accounting_init(&p->ioac);
	acct_clear_integrals(p);

	p->it_virt_expires = cputime_zero;
	p->it_prof_expires = cputime_zero;
	p->it_sched_expires = 0;
	INIT_LIST_HEAD(&p->cpu_timers[0]);
	INIT_LIST_HEAD(&p->cpu_timers[1]);
	INIT_LIST_HEAD(&p->cpu_timers[2]);

	p->lock_depth = -1;		/* -1 = no lock */
	do_posix_clock_monotonic_gettime(&p->start_time);
	p->real_start_time = p->start_time;
	monotonic_to_bootbased(&p->real_start_time);
#ifdef CONFIG_SECURITY
	p->security = NULL;
#endif
	p->cap_bset = current->cap_bset;
	p->io_context = NULL;
	p->audit_context = NULL;
	cgroup_fork(p);
#ifdef CONFIG_NUMA
	p->mempolicy = mpol_dup(p->mempolicy);
 	if (IS_ERR(p->mempolicy)) {
 		retval = PTR_ERR(p->mempolicy);
 		p->mempolicy = NULL;
 		goto bad_fork_cleanup_cgroup;
 	}
	mpol_fix_fork_child_flag(p);
#endif
#ifdef CONFIG_TRACE_IRQFLAGS
	p->irq_events = 0;
#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
	p->hardirqs_enabled = 1;
#else
	p->hardirqs_enabled = 0;
#endif
	p->hardirq_enable_ip = 0;
	p->hardirq_enable_event = 0;
	p->hardirq_disable_ip = _THIS_IP_;
	p->hardirq_disable_event = 0;
	p->softirqs_enabled = 1;
	p->softirq_enable_ip = _THIS_IP_;
	p->softirq_enable_event = 0;
	p->softirq_disable_ip = 0;
	p->softirq_disable_event = 0;
	p->hardirq_context = 0;
	p->softirq_context = 0;
#endif
#ifdef CONFIG_LOCKDEP
	p->lockdep_depth = 0; /* no locks held yet */
	p->curr_chain_key = 0;
	p->lockdep_recursion = 0;
#endif

#ifdef CONFIG_DEBUG_MUTEXES
	p->blocked_on = NULL; /* not blocked yet */
#endif

	/* Perform scheduler related setup. Assign this task to a CPU. */
	sched_fork(p, clone_flags);

	if ((retval = security_task_alloc(p)))
		goto bad_fork_cleanup_policy;
	if ((retval = audit_alloc(p)))
		goto bad_fork_cleanup_security;
	/* copy all the process information */
	if ((retval = copy_semundo(clone_flags, p)))
		goto bad_fork_cleanup_audit;
	if ((retval = copy_files(clone_flags, p)))
		goto bad_fork_cleanup_semundo;
	if ((retval = copy_fs(clone_flags, p)))
		goto bad_fork_cleanup_files;
	if ((retval = copy_sighand(clone_flags, p)))
		goto bad_fork_cleanup_fs;
	if ((retval = copy_signal(clone_flags, p)))
		goto bad_fork_cleanup_sighand;
	if ((retval = copy_mm(clone_flags, p)))
		goto bad_fork_cleanup_signal;
	if ((retval = copy_keys(clone_flags, p)))
		goto bad_fork_cleanup_mm;
	if ((retval = copy_namespaces(clone_flags, p)))
		goto bad_fork_cleanup_keys;
	if ((retval = copy_io(clone_flags, p)))
		goto bad_fork_cleanup_namespaces;
	retval = copy_thread(0, clone_flags, stack_start, stack_size, p, regs);
	if (retval)
		goto bad_fork_cleanup_io;

	if (pid != &init_struct_pid) {
		retval = -ENOMEM;
		pid = alloc_pid(task_active_pid_ns(p));
		if (!pid)
			goto bad_fork_cleanup_io;

		if (clone_flags & CLONE_NEWPID) {
			retval = pid_ns_prepare_proc(task_active_pid_ns(p));
			if (retval < 0)
				goto bad_fork_free_pid;
		}
	}

	p->pid = pid_nr(pid);
	p->tgid = p->pid;
	if (clone_flags & CLONE_THREAD)
		p->tgid = current->tgid;

	if (current->nsproxy != p->nsproxy) {
		retval = ns_cgroup_clone(p, pid);
		if (retval)
			goto bad_fork_free_pid;
	}

	p->set_child_tid = (clone_flags & CLONE_CHILD_SETTID) ? child_tidptr : NULL;
	/*
	 * Clear TID on mm_release()?
	 */
	p->clear_child_tid = (clone_flags & CLONE_CHILD_CLEARTID) ? child_tidptr: NULL;
#ifdef CONFIG_FUTEX
	p->robust_list = NULL;
#ifdef CONFIG_COMPAT
	p->compat_robust_list = NULL;
#endif
	INIT_LIST_HEAD(&p->pi_state_list);
	p->pi_state_cache = NULL;
#endif
	/*
	 * sigaltstack should be cleared when sharing the same VM
	 */
	if ((clone_flags & (CLONE_VM|CLONE_VFORK)) == CLONE_VM)
		p->sas_ss_sp = p->sas_ss_size = 0;

	/*
	 * Syscall tracing should be turned off in the child regardless
	 * of CLONE_PTRACE.
	 */
	clear_tsk_thread_flag(p, TIF_SYSCALL_TRACE);
#ifdef TIF_SYSCALL_EMU
	clear_tsk_thread_flag(p, TIF_SYSCALL_EMU);
#endif
	clear_all_latency_tracing(p);

	/* ok, now we should be set up.. */
	p->exit_signal = (clone_flags & CLONE_THREAD) ? -1 : (clone_flags & CSIGNAL);
	p->pdeath_signal = 0;
	p->exit_state = 0;

	/*
	 * Ok, make it visible to the rest of the system.
	 * We dont wake it up yet.
	 */
	p->group_leader = p;
	INIT_LIST_HEAD(&p->thread_group);

	/* Now that the task is set up, run cgroup callbacks if
	 * necessary. We need to run them before the task is visible
	 * on the tasklist. */
	cgroup_fork_callbacks(p);
	cgroup_callbacks_done = 1;

	/* Need tasklist lock for parent etc handling! */
	write_lock_irq(&tasklist_lock);

	/*
	 * The task hasn't been attached yet, so its cpus_allowed mask will
	 * not be changed, nor will its assigned CPU.
	 *
	 * The cpus_allowed mask of the parent may have changed after it was
	 * copied first time - so re-copy it here, then check the child's CPU
	 * to ensure it is on a valid CPU (and if not, just force it back to
	 * parent's CPU). This avoids alot of nasty races.
	 */
	p->cpus_allowed = current->cpus_allowed;
	if (unlikely(!cpu_isset(task_cpu(p), p->cpus_allowed) ||
			!cpu_online(task_cpu(p))))
		set_task_cpu(p, smp_processor_id());

	/* CLONE_PARENT re-uses the old parent */
	if (clone_flags & (CLONE_PARENT|CLONE_THREAD)) {
		p->real_parent = current->real_parent;
		p->parent_exec_id = current->parent_exec_id;
	} else {
		p->real_parent = current;
		p->parent_exec_id = current->self_exec_id;
	}

	spin_lock(&current->sighand->siglock);

	/*
	 * Process group and session signals need to be delivered to just the
	 * parent before the fork or both the parent and the child after the
	 * fork. Restart if a signal comes in before we add the new process to
	 * it's process group.
	 * A fatal signal pending means that current will exit, so the new
	 * thread can't slip out of an OOM kill (or normal SIGKILL).
 	 */
	recalc_sigpending();
	if (signal_pending(current)) {
		spin_unlock(&current->sighand->siglock);
		write_unlock_irq(&tasklist_lock);
		retval = -ERESTARTNOINTR;
		goto bad_fork_free_pid;
	}

	if (clone_flags & CLONE_THREAD) {
		atomic_inc(&current->signal->count);
		atomic_inc(&current->signal->live);
		p->group_leader = current->group_leader;
		list_add_tail_rcu(&p->thread_group, &p->group_leader->thread_group);

		if (!cputime_eq(current->signal->it_virt_expires,
				cputime_zero) ||
		    !cputime_eq(current->signal->it_prof_expires,
				cputime_zero) ||
		    current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY ||
		    !list_empty(&current->signal->cpu_timers[0]) ||
		    !list_empty(&current->signal->cpu_timers[1]) ||
		    !list_empty(&current->signal->cpu_timers[2])) {
			/*
			 * Have child wake up on its first tick to check
			 * for process CPU timers.
			 */
			p->it_prof_expires = jiffies_to_cputime(1);
		}
	}

	if (likely(p->pid)) {
		list_add_tail(&p->sibling, &p->real_parent->children);
		tracehook_finish_clone(p, clone_flags, trace);

		if (thread_group_leader(p)) {
			if (clone_flags & CLONE_NEWPID)
				p->nsproxy->pid_ns->child_reaper = p;

			p->signal->leader_pid = pid;
			p->signal->tty = current->signal->tty;
			set_task_pgrp(p, task_pgrp_nr(current));
			set_task_session(p, task_session_nr(current));
			attach_pid(p, PIDTYPE_PGID, task_pgrp(current));
			attach_pid(p, PIDTYPE_SID, task_session(current));
			list_add_tail_rcu(&p->tasks, &init_task.tasks);
			__get_cpu_var(process_counts)++;
		}
		attach_pid(p, PIDTYPE_PID, pid);
		nr_threads++;
	}

	total_forks++;
	spin_unlock(&current->sighand->siglock);
	write_unlock_irq(&tasklist_lock);
	proc_fork_connector(p);
	cgroup_post_fork(p);
	return p;

bad_fork_free_pid:
	if (pid != &init_struct_pid)
		free_pid(pid);
bad_fork_cleanup_io:
	put_io_context(p->io_context);
bad_fork_cleanup_namespaces:
	exit_task_namespaces(p);
bad_fork_cleanup_keys:
	exit_keys(p);
bad_fork_cleanup_mm:
	if (p->mm)
		mmput(p->mm);
bad_fork_cleanup_signal:
	if (!(clone_flags & CLONE_THREAD))
		__cleanup_signal(p->signal);
bad_fork_cleanup_sighand:
	__cleanup_sighand(p->sighand);
bad_fork_cleanup_fs:
	exit_fs(p); /* blocking */
bad_fork_cleanup_files:
	exit_files(p); /* blocking */
bad_fork_cleanup_semundo:
	exit_sem(p);
bad_fork_cleanup_audit:
	audit_free(p);
bad_fork_cleanup_security:
	security_task_free(p);
bad_fork_cleanup_policy:
#ifdef CONFIG_NUMA
	mpol_put(p->mempolicy);
bad_fork_cleanup_cgroup:
#endif
	cgroup_exit(p, cgroup_callbacks_done);
	delayacct_tsk_free(p);
	if (p->binfmt)
		module_put(p->binfmt->module);
bad_fork_cleanup_put_domain:
	module_put(task_thread_info(p)->exec_domain->module);
bad_fork_cleanup_count:
	put_group_info(p->group_info);
	atomic_dec(&p->user->processes);
	free_uid(p->user);
bad_fork_free:
	free_task(p);
fork_out:
	return ERR_PTR(retval);
}
Exemple #28
0
/* Free a reference on the credential and group info */
void
crfree(cred_t *cr)
{
	put_group_info(cr->group_info);
	put_cred((const cred_t *)cr);
}
struct rpc_cred *rpc_lookup_machine_cred(void)
{
	struct auth_cred acred = {
		.uid = RPC_MACHINE_CRED_USERID,
		.gid = RPC_MACHINE_CRED_GROUPID,
		.machine_cred = 1,
	};

	dprintk("RPC:       looking up machine cred\n");
	return generic_auth.au_ops->lookup_cred(&generic_auth, &acred, 0);
}
EXPORT_SYMBOL_GPL(rpc_lookup_machine_cred);

static void
generic_bind_cred(struct rpc_task *task, struct rpc_cred *cred, int lookupflags)
{
	struct rpc_auth *auth = task->tk_client->cl_auth;
	struct auth_cred *acred = &container_of(cred, struct generic_cred, gc_base)->acred;
	struct rpc_cred *ret;

	ret = auth->au_ops->lookup_cred(auth, acred, lookupflags);
	if (!IS_ERR(ret))
		task->tk_msg.rpc_cred = ret;
	else
		task->tk_status = PTR_ERR(ret);
}

static struct rpc_cred *
generic_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
{
	return rpcauth_lookup_credcache(&generic_auth, acred, flags);
}

static struct rpc_cred *
generic_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
{
	struct generic_cred *gcred;

	gcred = kmalloc(sizeof(*gcred), GFP_KERNEL);
	if (gcred == NULL)
		return ERR_PTR(-ENOMEM);

	rpcauth_init_cred(&gcred->gc_base, acred, &generic_auth, &generic_credops);
	gcred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE;

	gcred->acred.uid = acred->uid;
	gcred->acred.gid = acred->gid;
	gcred->acred.group_info = acred->group_info;
	if (gcred->acred.group_info != NULL)
		get_group_info(gcred->acred.group_info);
	gcred->acred.machine_cred = acred->machine_cred;

	dprintk("RPC:       allocated %s cred %p for uid %d gid %d\n",
			gcred->acred.machine_cred ? "machine" : "generic",
			gcred, acred->uid, acred->gid);
	return &gcred->gc_base;
}

static void
generic_free_cred(struct rpc_cred *cred)
{
	struct generic_cred *gcred = container_of(cred, struct generic_cred, gc_base);

	dprintk("RPC:       generic_free_cred %p\n", gcred);
	if (gcred->acred.group_info != NULL)
		put_group_info(gcred->acred.group_info);
	kfree(gcred);
}

static void
generic_free_cred_callback(struct rcu_head *head)
{
	struct rpc_cred *cred = container_of(head, struct rpc_cred, cr_rcu);
	generic_free_cred(cred);
}

static void
generic_destroy_cred(struct rpc_cred *cred)
{
	call_rcu(&cred->cr_rcu, generic_free_cred_callback);
}
int nfsd_setuser(struct svc_rqst *rqstp, struct svc_export *exp)
{
	struct svc_cred	cred = rqstp->rq_cred;
	int i;
	int flags = nfsexp_flags(rqstp, exp);
	int ret;

	if (flags & NFSEXP_ALLSQUASH) {
		cred.cr_uid = exp->ex_anon_uid;
		cred.cr_gid = exp->ex_anon_gid;
		cred.cr_group_info = groups_alloc(0);
	} else if (flags & NFSEXP_ROOTSQUASH) {
		struct group_info *gi;
		if (!cred.cr_uid)
			cred.cr_uid = exp->ex_anon_uid;
		if (!cred.cr_gid)
			cred.cr_gid = exp->ex_anon_gid;
		gi = groups_alloc(cred.cr_group_info->ngroups);
		if (gi)
			for (i = 0; i < cred.cr_group_info->ngroups; i++) {
				if (!GROUP_AT(cred.cr_group_info, i))
					GROUP_AT(gi, i) = exp->ex_anon_gid;
				else
					GROUP_AT(gi, i) = GROUP_AT(cred.cr_group_info, i);
			}
		cred.cr_group_info = gi;
	} else
		get_group_info(cred.cr_group_info);

	if (cred.cr_uid != (uid_t) -1)
		current->fsuid = cred.cr_uid;
	else
		current->fsuid = exp->ex_anon_uid;
	if (cred.cr_gid != (gid_t) -1)
		current->fsgid = cred.cr_gid;
	else
		current->fsgid = exp->ex_anon_gid;

	if (!cred.cr_group_info)
		return -ENOMEM;
	ret = set_current_groups(cred.cr_group_info);
	put_group_info(cred.cr_group_info);
	if ((cred.cr_uid)) {
		current->cap_effective =
			cap_drop_nfsd_set(current->cap_effective);
	} else {
		current->cap_effective =
			cap_raise_nfsd_set(current->cap_effective,
					   current->cap_permitted);
	}
	return ret;
}