906 строки
20 KiB
C
906 строки
20 KiB
C
/*
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* Copyright (C) 2002,2003 by Andreas Gruenbacher <a.gruenbacher@computer.org>
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*
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* Fixes from William Schumacher incorporated on 15 March 2001.
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* (Reported by Charles Bertsch, <CBertsch@microtest.com>).
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*/
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/*
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* This file contains generic functions for manipulating
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* POSIX 1003.1e draft standard 17 ACLs.
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*/
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/atomic.h>
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#include <linux/fs.h>
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#include <linux/sched.h>
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#include <linux/posix_acl.h>
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#include <linux/posix_acl_xattr.h>
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#include <linux/xattr.h>
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#include <linux/export.h>
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#include <linux/user_namespace.h>
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struct posix_acl **acl_by_type(struct inode *inode, int type)
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{
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switch (type) {
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case ACL_TYPE_ACCESS:
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return &inode->i_acl;
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case ACL_TYPE_DEFAULT:
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return &inode->i_default_acl;
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default:
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BUG();
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}
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}
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EXPORT_SYMBOL(acl_by_type);
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struct posix_acl *get_cached_acl(struct inode *inode, int type)
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{
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struct posix_acl **p = acl_by_type(inode, type);
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struct posix_acl *acl = ACCESS_ONCE(*p);
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if (acl) {
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spin_lock(&inode->i_lock);
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acl = *p;
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if (acl != ACL_NOT_CACHED)
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acl = posix_acl_dup(acl);
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spin_unlock(&inode->i_lock);
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}
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return acl;
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}
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EXPORT_SYMBOL(get_cached_acl);
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struct posix_acl *get_cached_acl_rcu(struct inode *inode, int type)
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{
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return rcu_dereference(*acl_by_type(inode, type));
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}
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EXPORT_SYMBOL(get_cached_acl_rcu);
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void set_cached_acl(struct inode *inode, int type, struct posix_acl *acl)
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{
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struct posix_acl **p = acl_by_type(inode, type);
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struct posix_acl *old;
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spin_lock(&inode->i_lock);
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old = *p;
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rcu_assign_pointer(*p, posix_acl_dup(acl));
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spin_unlock(&inode->i_lock);
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if (old != ACL_NOT_CACHED)
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posix_acl_release(old);
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}
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EXPORT_SYMBOL(set_cached_acl);
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void forget_cached_acl(struct inode *inode, int type)
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{
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struct posix_acl **p = acl_by_type(inode, type);
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struct posix_acl *old;
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spin_lock(&inode->i_lock);
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old = *p;
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*p = ACL_NOT_CACHED;
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spin_unlock(&inode->i_lock);
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if (old != ACL_NOT_CACHED)
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posix_acl_release(old);
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}
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EXPORT_SYMBOL(forget_cached_acl);
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void forget_all_cached_acls(struct inode *inode)
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{
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struct posix_acl *old_access, *old_default;
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spin_lock(&inode->i_lock);
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old_access = inode->i_acl;
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old_default = inode->i_default_acl;
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inode->i_acl = inode->i_default_acl = ACL_NOT_CACHED;
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spin_unlock(&inode->i_lock);
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if (old_access != ACL_NOT_CACHED)
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posix_acl_release(old_access);
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if (old_default != ACL_NOT_CACHED)
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posix_acl_release(old_default);
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}
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EXPORT_SYMBOL(forget_all_cached_acls);
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struct posix_acl *get_acl(struct inode *inode, int type)
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{
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struct posix_acl *acl;
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acl = get_cached_acl(inode, type);
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if (acl != ACL_NOT_CACHED)
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return acl;
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if (!IS_POSIXACL(inode))
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return NULL;
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/*
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* A filesystem can force a ACL callback by just never filling the
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* ACL cache. But normally you'd fill the cache either at inode
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* instantiation time, or on the first ->get_acl call.
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*
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* If the filesystem doesn't have a get_acl() function at all, we'll
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* just create the negative cache entry.
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*/
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if (!inode->i_op->get_acl) {
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set_cached_acl(inode, type, NULL);
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return NULL;
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}
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return inode->i_op->get_acl(inode, type);
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}
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EXPORT_SYMBOL(get_acl);
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/*
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* Init a fresh posix_acl
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*/
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void
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posix_acl_init(struct posix_acl *acl, int count)
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{
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atomic_set(&acl->a_refcount, 1);
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acl->a_count = count;
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}
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EXPORT_SYMBOL(posix_acl_init);
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/*
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* Allocate a new ACL with the specified number of entries.
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*/
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struct posix_acl *
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posix_acl_alloc(int count, gfp_t flags)
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{
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const size_t size = sizeof(struct posix_acl) +
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count * sizeof(struct posix_acl_entry);
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struct posix_acl *acl = kmalloc(size, flags);
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if (acl)
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posix_acl_init(acl, count);
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return acl;
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}
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EXPORT_SYMBOL(posix_acl_alloc);
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/*
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* Clone an ACL.
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*/
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static struct posix_acl *
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posix_acl_clone(const struct posix_acl *acl, gfp_t flags)
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{
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struct posix_acl *clone = NULL;
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if (acl) {
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int size = sizeof(struct posix_acl) + acl->a_count *
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sizeof(struct posix_acl_entry);
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clone = kmemdup(acl, size, flags);
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if (clone)
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atomic_set(&clone->a_refcount, 1);
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}
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return clone;
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}
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/*
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* Check if an acl is valid. Returns 0 if it is, or -E... otherwise.
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*/
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int
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posix_acl_valid(const struct posix_acl *acl)
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{
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const struct posix_acl_entry *pa, *pe;
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int state = ACL_USER_OBJ;
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int needs_mask = 0;
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FOREACH_ACL_ENTRY(pa, acl, pe) {
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if (pa->e_perm & ~(ACL_READ|ACL_WRITE|ACL_EXECUTE))
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return -EINVAL;
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switch (pa->e_tag) {
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case ACL_USER_OBJ:
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if (state == ACL_USER_OBJ) {
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state = ACL_USER;
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break;
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}
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return -EINVAL;
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case ACL_USER:
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if (state != ACL_USER)
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return -EINVAL;
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if (!uid_valid(pa->e_uid))
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return -EINVAL;
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needs_mask = 1;
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break;
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case ACL_GROUP_OBJ:
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if (state == ACL_USER) {
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state = ACL_GROUP;
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break;
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}
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return -EINVAL;
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case ACL_GROUP:
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if (state != ACL_GROUP)
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return -EINVAL;
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if (!gid_valid(pa->e_gid))
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return -EINVAL;
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needs_mask = 1;
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break;
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case ACL_MASK:
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if (state != ACL_GROUP)
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return -EINVAL;
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state = ACL_OTHER;
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break;
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case ACL_OTHER:
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if (state == ACL_OTHER ||
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(state == ACL_GROUP && !needs_mask)) {
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state = 0;
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break;
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}
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return -EINVAL;
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default:
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return -EINVAL;
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}
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}
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if (state == 0)
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return 0;
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return -EINVAL;
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}
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EXPORT_SYMBOL(posix_acl_valid);
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/*
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* Returns 0 if the acl can be exactly represented in the traditional
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* file mode permission bits, or else 1. Returns -E... on error.
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*/
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int
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posix_acl_equiv_mode(const struct posix_acl *acl, umode_t *mode_p)
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{
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const struct posix_acl_entry *pa, *pe;
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umode_t mode = 0;
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int not_equiv = 0;
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/*
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* A null ACL can always be presented as mode bits.
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*/
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if (!acl)
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return 0;
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FOREACH_ACL_ENTRY(pa, acl, pe) {
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switch (pa->e_tag) {
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case ACL_USER_OBJ:
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mode |= (pa->e_perm & S_IRWXO) << 6;
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break;
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case ACL_GROUP_OBJ:
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mode |= (pa->e_perm & S_IRWXO) << 3;
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break;
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case ACL_OTHER:
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mode |= pa->e_perm & S_IRWXO;
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break;
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case ACL_MASK:
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mode = (mode & ~S_IRWXG) |
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((pa->e_perm & S_IRWXO) << 3);
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not_equiv = 1;
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break;
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case ACL_USER:
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case ACL_GROUP:
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not_equiv = 1;
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break;
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default:
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return -EINVAL;
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}
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}
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if (mode_p)
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*mode_p = (*mode_p & ~S_IRWXUGO) | mode;
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return not_equiv;
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}
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EXPORT_SYMBOL(posix_acl_equiv_mode);
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/*
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* Create an ACL representing the file mode permission bits of an inode.
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*/
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struct posix_acl *
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posix_acl_from_mode(umode_t mode, gfp_t flags)
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{
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struct posix_acl *acl = posix_acl_alloc(3, flags);
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if (!acl)
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return ERR_PTR(-ENOMEM);
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acl->a_entries[0].e_tag = ACL_USER_OBJ;
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acl->a_entries[0].e_perm = (mode & S_IRWXU) >> 6;
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acl->a_entries[1].e_tag = ACL_GROUP_OBJ;
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acl->a_entries[1].e_perm = (mode & S_IRWXG) >> 3;
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acl->a_entries[2].e_tag = ACL_OTHER;
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acl->a_entries[2].e_perm = (mode & S_IRWXO);
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return acl;
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}
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EXPORT_SYMBOL(posix_acl_from_mode);
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/*
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* Return 0 if current is granted want access to the inode
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* by the acl. Returns -E... otherwise.
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*/
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int
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posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want)
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{
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const struct posix_acl_entry *pa, *pe, *mask_obj;
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int found = 0;
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want &= MAY_READ | MAY_WRITE | MAY_EXEC | MAY_NOT_BLOCK;
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FOREACH_ACL_ENTRY(pa, acl, pe) {
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switch(pa->e_tag) {
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case ACL_USER_OBJ:
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/* (May have been checked already) */
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if (uid_eq(inode->i_uid, current_fsuid()))
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goto check_perm;
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break;
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case ACL_USER:
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if (uid_eq(pa->e_uid, current_fsuid()))
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goto mask;
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break;
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case ACL_GROUP_OBJ:
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if (in_group_p(inode->i_gid)) {
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found = 1;
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if ((pa->e_perm & want) == want)
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goto mask;
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}
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break;
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case ACL_GROUP:
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if (in_group_p(pa->e_gid)) {
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found = 1;
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if ((pa->e_perm & want) == want)
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goto mask;
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}
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break;
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case ACL_MASK:
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break;
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case ACL_OTHER:
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if (found)
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return -EACCES;
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else
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goto check_perm;
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default:
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return -EIO;
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}
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}
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return -EIO;
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mask:
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for (mask_obj = pa+1; mask_obj != pe; mask_obj++) {
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if (mask_obj->e_tag == ACL_MASK) {
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if ((pa->e_perm & mask_obj->e_perm & want) == want)
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return 0;
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return -EACCES;
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}
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}
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check_perm:
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if ((pa->e_perm & want) == want)
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return 0;
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return -EACCES;
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}
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/*
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* Modify acl when creating a new inode. The caller must ensure the acl is
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* only referenced once.
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*
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* mode_p initially must contain the mode parameter to the open() / creat()
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* system calls. All permissions that are not granted by the acl are removed.
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* The permissions in the acl are changed to reflect the mode_p parameter.
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*/
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static int posix_acl_create_masq(struct posix_acl *acl, umode_t *mode_p)
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{
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struct posix_acl_entry *pa, *pe;
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struct posix_acl_entry *group_obj = NULL, *mask_obj = NULL;
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umode_t mode = *mode_p;
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int not_equiv = 0;
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/* assert(atomic_read(acl->a_refcount) == 1); */
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FOREACH_ACL_ENTRY(pa, acl, pe) {
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switch(pa->e_tag) {
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case ACL_USER_OBJ:
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pa->e_perm &= (mode >> 6) | ~S_IRWXO;
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mode &= (pa->e_perm << 6) | ~S_IRWXU;
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break;
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case ACL_USER:
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case ACL_GROUP:
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not_equiv = 1;
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break;
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case ACL_GROUP_OBJ:
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group_obj = pa;
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break;
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case ACL_OTHER:
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pa->e_perm &= mode | ~S_IRWXO;
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mode &= pa->e_perm | ~S_IRWXO;
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break;
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case ACL_MASK:
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mask_obj = pa;
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not_equiv = 1;
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break;
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default:
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return -EIO;
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}
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}
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if (mask_obj) {
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mask_obj->e_perm &= (mode >> 3) | ~S_IRWXO;
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mode &= (mask_obj->e_perm << 3) | ~S_IRWXG;
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} else {
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if (!group_obj)
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return -EIO;
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group_obj->e_perm &= (mode >> 3) | ~S_IRWXO;
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mode &= (group_obj->e_perm << 3) | ~S_IRWXG;
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}
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*mode_p = (*mode_p & ~S_IRWXUGO) | mode;
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return not_equiv;
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}
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/*
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* Modify the ACL for the chmod syscall.
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*/
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static int __posix_acl_chmod_masq(struct posix_acl *acl, umode_t mode)
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{
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struct posix_acl_entry *group_obj = NULL, *mask_obj = NULL;
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struct posix_acl_entry *pa, *pe;
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/* assert(atomic_read(acl->a_refcount) == 1); */
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FOREACH_ACL_ENTRY(pa, acl, pe) {
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switch(pa->e_tag) {
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case ACL_USER_OBJ:
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pa->e_perm = (mode & S_IRWXU) >> 6;
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break;
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case ACL_USER:
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case ACL_GROUP:
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break;
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case ACL_GROUP_OBJ:
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group_obj = pa;
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break;
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case ACL_MASK:
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mask_obj = pa;
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break;
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case ACL_OTHER:
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pa->e_perm = (mode & S_IRWXO);
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break;
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default:
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return -EIO;
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}
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}
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if (mask_obj) {
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mask_obj->e_perm = (mode & S_IRWXG) >> 3;
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} else {
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if (!group_obj)
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return -EIO;
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group_obj->e_perm = (mode & S_IRWXG) >> 3;
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}
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return 0;
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}
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int
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__posix_acl_create(struct posix_acl **acl, gfp_t gfp, umode_t *mode_p)
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{
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struct posix_acl *clone = posix_acl_clone(*acl, gfp);
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int err = -ENOMEM;
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if (clone) {
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err = posix_acl_create_masq(clone, mode_p);
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if (err < 0) {
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posix_acl_release(clone);
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clone = NULL;
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}
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}
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posix_acl_release(*acl);
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*acl = clone;
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return err;
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}
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EXPORT_SYMBOL(__posix_acl_create);
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int
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__posix_acl_chmod(struct posix_acl **acl, gfp_t gfp, umode_t mode)
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{
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struct posix_acl *clone = posix_acl_clone(*acl, gfp);
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int err = -ENOMEM;
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if (clone) {
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err = __posix_acl_chmod_masq(clone, mode);
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if (err) {
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posix_acl_release(clone);
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clone = NULL;
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}
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}
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posix_acl_release(*acl);
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*acl = clone;
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return err;
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}
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EXPORT_SYMBOL(__posix_acl_chmod);
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int
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posix_acl_chmod(struct inode *inode, umode_t mode)
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{
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struct posix_acl *acl;
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int ret = 0;
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if (!IS_POSIXACL(inode))
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return 0;
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if (!inode->i_op->set_acl)
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return -EOPNOTSUPP;
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acl = get_acl(inode, ACL_TYPE_ACCESS);
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if (IS_ERR_OR_NULL(acl)) {
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if (acl == ERR_PTR(-EOPNOTSUPP))
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return 0;
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return PTR_ERR(acl);
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}
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ret = __posix_acl_chmod(&acl, GFP_KERNEL, mode);
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if (ret)
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return ret;
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ret = inode->i_op->set_acl(inode, acl, ACL_TYPE_ACCESS);
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posix_acl_release(acl);
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return ret;
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}
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EXPORT_SYMBOL(posix_acl_chmod);
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int
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posix_acl_create(struct inode *dir, umode_t *mode,
|
|
struct posix_acl **default_acl, struct posix_acl **acl)
|
|
{
|
|
struct posix_acl *p;
|
|
int ret;
|
|
|
|
if (S_ISLNK(*mode) || !IS_POSIXACL(dir))
|
|
goto no_acl;
|
|
|
|
p = get_acl(dir, ACL_TYPE_DEFAULT);
|
|
if (IS_ERR(p)) {
|
|
if (p == ERR_PTR(-EOPNOTSUPP))
|
|
goto apply_umask;
|
|
return PTR_ERR(p);
|
|
}
|
|
|
|
if (!p)
|
|
goto apply_umask;
|
|
|
|
*acl = posix_acl_clone(p, GFP_NOFS);
|
|
if (!*acl)
|
|
goto no_mem;
|
|
|
|
ret = posix_acl_create_masq(*acl, mode);
|
|
if (ret < 0)
|
|
goto no_mem_clone;
|
|
|
|
if (ret == 0) {
|
|
posix_acl_release(*acl);
|
|
*acl = NULL;
|
|
}
|
|
|
|
if (!S_ISDIR(*mode)) {
|
|
posix_acl_release(p);
|
|
*default_acl = NULL;
|
|
} else {
|
|
*default_acl = p;
|
|
}
|
|
return 0;
|
|
|
|
apply_umask:
|
|
*mode &= ~current_umask();
|
|
no_acl:
|
|
*default_acl = NULL;
|
|
*acl = NULL;
|
|
return 0;
|
|
|
|
no_mem_clone:
|
|
posix_acl_release(*acl);
|
|
no_mem:
|
|
posix_acl_release(p);
|
|
return -ENOMEM;
|
|
}
|
|
EXPORT_SYMBOL_GPL(posix_acl_create);
|
|
|
|
/*
|
|
* Fix up the uids and gids in posix acl extended attributes in place.
|
|
*/
|
|
static void posix_acl_fix_xattr_userns(
|
|
struct user_namespace *to, struct user_namespace *from,
|
|
void *value, size_t size)
|
|
{
|
|
posix_acl_xattr_header *header = (posix_acl_xattr_header *)value;
|
|
posix_acl_xattr_entry *entry = (posix_acl_xattr_entry *)(header+1), *end;
|
|
int count;
|
|
kuid_t uid;
|
|
kgid_t gid;
|
|
|
|
if (!value)
|
|
return;
|
|
if (size < sizeof(posix_acl_xattr_header))
|
|
return;
|
|
if (header->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION))
|
|
return;
|
|
|
|
count = posix_acl_xattr_count(size);
|
|
if (count < 0)
|
|
return;
|
|
if (count == 0)
|
|
return;
|
|
|
|
for (end = entry + count; entry != end; entry++) {
|
|
switch(le16_to_cpu(entry->e_tag)) {
|
|
case ACL_USER:
|
|
uid = make_kuid(from, le32_to_cpu(entry->e_id));
|
|
entry->e_id = cpu_to_le32(from_kuid(to, uid));
|
|
break;
|
|
case ACL_GROUP:
|
|
gid = make_kgid(from, le32_to_cpu(entry->e_id));
|
|
entry->e_id = cpu_to_le32(from_kgid(to, gid));
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
void posix_acl_fix_xattr_from_user(void *value, size_t size)
|
|
{
|
|
struct user_namespace *user_ns = current_user_ns();
|
|
if (user_ns == &init_user_ns)
|
|
return;
|
|
posix_acl_fix_xattr_userns(&init_user_ns, user_ns, value, size);
|
|
}
|
|
|
|
void posix_acl_fix_xattr_to_user(void *value, size_t size)
|
|
{
|
|
struct user_namespace *user_ns = current_user_ns();
|
|
if (user_ns == &init_user_ns)
|
|
return;
|
|
posix_acl_fix_xattr_userns(user_ns, &init_user_ns, value, size);
|
|
}
|
|
|
|
/*
|
|
* Convert from extended attribute to in-memory representation.
|
|
*/
|
|
struct posix_acl *
|
|
posix_acl_from_xattr(struct user_namespace *user_ns,
|
|
const void *value, size_t size)
|
|
{
|
|
posix_acl_xattr_header *header = (posix_acl_xattr_header *)value;
|
|
posix_acl_xattr_entry *entry = (posix_acl_xattr_entry *)(header+1), *end;
|
|
int count;
|
|
struct posix_acl *acl;
|
|
struct posix_acl_entry *acl_e;
|
|
|
|
if (!value)
|
|
return NULL;
|
|
if (size < sizeof(posix_acl_xattr_header))
|
|
return ERR_PTR(-EINVAL);
|
|
if (header->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION))
|
|
return ERR_PTR(-EOPNOTSUPP);
|
|
|
|
count = posix_acl_xattr_count(size);
|
|
if (count < 0)
|
|
return ERR_PTR(-EINVAL);
|
|
if (count == 0)
|
|
return NULL;
|
|
|
|
acl = posix_acl_alloc(count, GFP_NOFS);
|
|
if (!acl)
|
|
return ERR_PTR(-ENOMEM);
|
|
acl_e = acl->a_entries;
|
|
|
|
for (end = entry + count; entry != end; acl_e++, entry++) {
|
|
acl_e->e_tag = le16_to_cpu(entry->e_tag);
|
|
acl_e->e_perm = le16_to_cpu(entry->e_perm);
|
|
|
|
switch(acl_e->e_tag) {
|
|
case ACL_USER_OBJ:
|
|
case ACL_GROUP_OBJ:
|
|
case ACL_MASK:
|
|
case ACL_OTHER:
|
|
break;
|
|
|
|
case ACL_USER:
|
|
acl_e->e_uid =
|
|
make_kuid(user_ns,
|
|
le32_to_cpu(entry->e_id));
|
|
if (!uid_valid(acl_e->e_uid))
|
|
goto fail;
|
|
break;
|
|
case ACL_GROUP:
|
|
acl_e->e_gid =
|
|
make_kgid(user_ns,
|
|
le32_to_cpu(entry->e_id));
|
|
if (!gid_valid(acl_e->e_gid))
|
|
goto fail;
|
|
break;
|
|
|
|
default:
|
|
goto fail;
|
|
}
|
|
}
|
|
return acl;
|
|
|
|
fail:
|
|
posix_acl_release(acl);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
EXPORT_SYMBOL (posix_acl_from_xattr);
|
|
|
|
/*
|
|
* Convert from in-memory to extended attribute representation.
|
|
*/
|
|
int
|
|
posix_acl_to_xattr(struct user_namespace *user_ns, const struct posix_acl *acl,
|
|
void *buffer, size_t size)
|
|
{
|
|
posix_acl_xattr_header *ext_acl = (posix_acl_xattr_header *)buffer;
|
|
posix_acl_xattr_entry *ext_entry;
|
|
int real_size, n;
|
|
|
|
real_size = posix_acl_xattr_size(acl->a_count);
|
|
if (!buffer)
|
|
return real_size;
|
|
if (real_size > size)
|
|
return -ERANGE;
|
|
|
|
ext_entry = ext_acl->a_entries;
|
|
ext_acl->a_version = cpu_to_le32(POSIX_ACL_XATTR_VERSION);
|
|
|
|
for (n=0; n < acl->a_count; n++, ext_entry++) {
|
|
const struct posix_acl_entry *acl_e = &acl->a_entries[n];
|
|
ext_entry->e_tag = cpu_to_le16(acl_e->e_tag);
|
|
ext_entry->e_perm = cpu_to_le16(acl_e->e_perm);
|
|
switch(acl_e->e_tag) {
|
|
case ACL_USER:
|
|
ext_entry->e_id =
|
|
cpu_to_le32(from_kuid(user_ns, acl_e->e_uid));
|
|
break;
|
|
case ACL_GROUP:
|
|
ext_entry->e_id =
|
|
cpu_to_le32(from_kgid(user_ns, acl_e->e_gid));
|
|
break;
|
|
default:
|
|
ext_entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID);
|
|
break;
|
|
}
|
|
}
|
|
return real_size;
|
|
}
|
|
EXPORT_SYMBOL (posix_acl_to_xattr);
|
|
|
|
static int
|
|
posix_acl_xattr_get(struct dentry *dentry, const char *name,
|
|
void *value, size_t size, int type)
|
|
{
|
|
struct posix_acl *acl;
|
|
int error;
|
|
|
|
if (!IS_POSIXACL(d_backing_inode(dentry)))
|
|
return -EOPNOTSUPP;
|
|
if (d_is_symlink(dentry))
|
|
return -EOPNOTSUPP;
|
|
|
|
acl = get_acl(d_backing_inode(dentry), type);
|
|
if (IS_ERR(acl))
|
|
return PTR_ERR(acl);
|
|
if (acl == NULL)
|
|
return -ENODATA;
|
|
|
|
error = posix_acl_to_xattr(&init_user_ns, acl, value, size);
|
|
posix_acl_release(acl);
|
|
|
|
return error;
|
|
}
|
|
|
|
static int
|
|
posix_acl_xattr_set(struct dentry *dentry, const char *name,
|
|
const void *value, size_t size, int flags, int type)
|
|
{
|
|
struct inode *inode = d_backing_inode(dentry);
|
|
struct posix_acl *acl = NULL;
|
|
int ret;
|
|
|
|
if (!IS_POSIXACL(inode))
|
|
return -EOPNOTSUPP;
|
|
if (!inode->i_op->set_acl)
|
|
return -EOPNOTSUPP;
|
|
|
|
if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode))
|
|
return value ? -EACCES : 0;
|
|
if (!inode_owner_or_capable(inode))
|
|
return -EPERM;
|
|
|
|
if (value) {
|
|
acl = posix_acl_from_xattr(&init_user_ns, value, size);
|
|
if (IS_ERR(acl))
|
|
return PTR_ERR(acl);
|
|
|
|
if (acl) {
|
|
ret = posix_acl_valid(acl);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
ret = inode->i_op->set_acl(inode, acl, type);
|
|
out:
|
|
posix_acl_release(acl);
|
|
return ret;
|
|
}
|
|
|
|
static size_t
|
|
posix_acl_xattr_list(struct dentry *dentry, char *list, size_t list_size,
|
|
const char *name, size_t name_len, int type)
|
|
{
|
|
const char *xname;
|
|
size_t size;
|
|
|
|
if (!IS_POSIXACL(d_backing_inode(dentry)))
|
|
return -EOPNOTSUPP;
|
|
if (d_is_symlink(dentry))
|
|
return -EOPNOTSUPP;
|
|
|
|
if (type == ACL_TYPE_ACCESS)
|
|
xname = POSIX_ACL_XATTR_ACCESS;
|
|
else
|
|
xname = POSIX_ACL_XATTR_DEFAULT;
|
|
|
|
size = strlen(xname) + 1;
|
|
if (list && size <= list_size)
|
|
memcpy(list, xname, size);
|
|
return size;
|
|
}
|
|
|
|
const struct xattr_handler posix_acl_access_xattr_handler = {
|
|
.prefix = POSIX_ACL_XATTR_ACCESS,
|
|
.flags = ACL_TYPE_ACCESS,
|
|
.list = posix_acl_xattr_list,
|
|
.get = posix_acl_xattr_get,
|
|
.set = posix_acl_xattr_set,
|
|
};
|
|
EXPORT_SYMBOL_GPL(posix_acl_access_xattr_handler);
|
|
|
|
const struct xattr_handler posix_acl_default_xattr_handler = {
|
|
.prefix = POSIX_ACL_XATTR_DEFAULT,
|
|
.flags = ACL_TYPE_DEFAULT,
|
|
.list = posix_acl_xattr_list,
|
|
.get = posix_acl_xattr_get,
|
|
.set = posix_acl_xattr_set,
|
|
};
|
|
EXPORT_SYMBOL_GPL(posix_acl_default_xattr_handler);
|
|
|
|
int simple_set_acl(struct inode *inode, struct posix_acl *acl, int type)
|
|
{
|
|
int error;
|
|
|
|
if (type == ACL_TYPE_ACCESS) {
|
|
error = posix_acl_equiv_mode(acl, &inode->i_mode);
|
|
if (error < 0)
|
|
return 0;
|
|
if (error == 0)
|
|
acl = NULL;
|
|
}
|
|
|
|
inode->i_ctime = CURRENT_TIME;
|
|
set_cached_acl(inode, type, acl);
|
|
return 0;
|
|
}
|
|
|
|
int simple_acl_create(struct inode *dir, struct inode *inode)
|
|
{
|
|
struct posix_acl *default_acl, *acl;
|
|
int error;
|
|
|
|
error = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
|
|
if (error)
|
|
return error;
|
|
|
|
set_cached_acl(inode, ACL_TYPE_DEFAULT, default_acl);
|
|
set_cached_acl(inode, ACL_TYPE_ACCESS, acl);
|
|
|
|
if (default_acl)
|
|
posix_acl_release(default_acl);
|
|
if (acl)
|
|
posix_acl_release(acl);
|
|
return 0;
|
|
}
|