diff options
Diffstat (limited to 'fs/f2fs/acl.c')
| -rw-r--r-- | fs/f2fs/acl.c | 443 |
1 files changed, 443 insertions, 0 deletions
diff --git a/fs/f2fs/acl.c b/fs/f2fs/acl.c new file mode 100644 index 0000000000..ec2aeccb69 --- /dev/null +++ b/fs/f2fs/acl.c @@ -0,0 +1,443 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * fs/f2fs/acl.c + * + * Copyright (c) 2012 Samsung Electronics Co., Ltd. + * http://www.samsung.com/ + * + * Portions of this code from linux/fs/ext2/acl.c + * + * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de> + */ +#include <linux/f2fs_fs.h> +#include "f2fs.h" +#include "xattr.h" +#include "acl.h" + +static inline size_t f2fs_acl_size(int count) +{ + if (count <= 4) { + return sizeof(struct f2fs_acl_header) + + count * sizeof(struct f2fs_acl_entry_short); + } else { + return sizeof(struct f2fs_acl_header) + + 4 * sizeof(struct f2fs_acl_entry_short) + + (count - 4) * sizeof(struct f2fs_acl_entry); + } +} + +static inline int f2fs_acl_count(size_t size) +{ + ssize_t s; + + size -= sizeof(struct f2fs_acl_header); + s = size - 4 * sizeof(struct f2fs_acl_entry_short); + if (s < 0) { + if (size % sizeof(struct f2fs_acl_entry_short)) + return -1; + return size / sizeof(struct f2fs_acl_entry_short); + } else { + if (s % sizeof(struct f2fs_acl_entry)) + return -1; + return s / sizeof(struct f2fs_acl_entry) + 4; + } +} + +static struct posix_acl *f2fs_acl_from_disk(const char *value, size_t size) +{ + int i, count; + struct posix_acl *acl; + struct f2fs_acl_header *hdr = (struct f2fs_acl_header *)value; + struct f2fs_acl_entry *entry = (struct f2fs_acl_entry *)(hdr + 1); + const char *end = value + size; + + if (size < sizeof(struct f2fs_acl_header)) + return ERR_PTR(-EINVAL); + + if (hdr->a_version != cpu_to_le32(F2FS_ACL_VERSION)) + return ERR_PTR(-EINVAL); + + count = f2fs_acl_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); + + for (i = 0; i < count; i++) { + + if ((char *)entry > end) + goto fail; + + acl->a_entries[i].e_tag = le16_to_cpu(entry->e_tag); + acl->a_entries[i].e_perm = le16_to_cpu(entry->e_perm); + + switch (acl->a_entries[i].e_tag) { + case ACL_USER_OBJ: + case ACL_GROUP_OBJ: + case ACL_MASK: + case ACL_OTHER: + entry = (struct f2fs_acl_entry *)((char *)entry + + sizeof(struct f2fs_acl_entry_short)); + break; + + case ACL_USER: + acl->a_entries[i].e_uid = + make_kuid(&init_user_ns, + le32_to_cpu(entry->e_id)); + entry = (struct f2fs_acl_entry *)((char *)entry + + sizeof(struct f2fs_acl_entry)); + break; + case ACL_GROUP: + acl->a_entries[i].e_gid = + make_kgid(&init_user_ns, + le32_to_cpu(entry->e_id)); + entry = (struct f2fs_acl_entry *)((char *)entry + + sizeof(struct f2fs_acl_entry)); + break; + default: + goto fail; + } + } + if ((char *)entry != end) + goto fail; + return acl; +fail: + posix_acl_release(acl); + return ERR_PTR(-EINVAL); +} + +static void *f2fs_acl_to_disk(struct f2fs_sb_info *sbi, + const struct posix_acl *acl, size_t *size) +{ + struct f2fs_acl_header *f2fs_acl; + struct f2fs_acl_entry *entry; + int i; + + f2fs_acl = f2fs_kmalloc(sbi, sizeof(struct f2fs_acl_header) + + acl->a_count * sizeof(struct f2fs_acl_entry), + GFP_NOFS); + if (!f2fs_acl) + return ERR_PTR(-ENOMEM); + + f2fs_acl->a_version = cpu_to_le32(F2FS_ACL_VERSION); + entry = (struct f2fs_acl_entry *)(f2fs_acl + 1); + + for (i = 0; i < acl->a_count; i++) { + + entry->e_tag = cpu_to_le16(acl->a_entries[i].e_tag); + entry->e_perm = cpu_to_le16(acl->a_entries[i].e_perm); + + switch (acl->a_entries[i].e_tag) { + case ACL_USER: + entry->e_id = cpu_to_le32( + from_kuid(&init_user_ns, + acl->a_entries[i].e_uid)); + entry = (struct f2fs_acl_entry *)((char *)entry + + sizeof(struct f2fs_acl_entry)); + break; + case ACL_GROUP: + entry->e_id = cpu_to_le32( + from_kgid(&init_user_ns, + acl->a_entries[i].e_gid)); + entry = (struct f2fs_acl_entry *)((char *)entry + + sizeof(struct f2fs_acl_entry)); + break; + case ACL_USER_OBJ: + case ACL_GROUP_OBJ: + case ACL_MASK: + case ACL_OTHER: + entry = (struct f2fs_acl_entry *)((char *)entry + + sizeof(struct f2fs_acl_entry_short)); + break; + default: + goto fail; + } + } + *size = f2fs_acl_size(acl->a_count); + return (void *)f2fs_acl; + +fail: + kfree(f2fs_acl); + return ERR_PTR(-EINVAL); +} + +static struct posix_acl *__f2fs_get_acl(struct inode *inode, int type, + struct page *dpage) +{ + int name_index = F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT; + void *value = NULL; + struct posix_acl *acl; + int retval; + + if (type == ACL_TYPE_ACCESS) + name_index = F2FS_XATTR_INDEX_POSIX_ACL_ACCESS; + + retval = f2fs_getxattr(inode, name_index, "", NULL, 0, dpage); + if (retval > 0) { + value = f2fs_kmalloc(F2FS_I_SB(inode), retval, GFP_F2FS_ZERO); + if (!value) + return ERR_PTR(-ENOMEM); + retval = f2fs_getxattr(inode, name_index, "", value, + retval, dpage); + } + + if (retval > 0) + acl = f2fs_acl_from_disk(value, retval); + else if (retval == -ENODATA) + acl = NULL; + else + acl = ERR_PTR(retval); + kfree(value); + + return acl; +} + +struct posix_acl *f2fs_get_acl(struct inode *inode, int type, bool rcu) +{ + if (rcu) + return ERR_PTR(-ECHILD); + + return __f2fs_get_acl(inode, type, NULL); +} + +static int f2fs_acl_update_mode(struct mnt_idmap *idmap, + struct inode *inode, umode_t *mode_p, + struct posix_acl **acl) +{ + umode_t mode = inode->i_mode; + int error; + + if (is_inode_flag_set(inode, FI_ACL_MODE)) + mode = F2FS_I(inode)->i_acl_mode; + + error = posix_acl_equiv_mode(*acl, &mode); + if (error < 0) + return error; + if (error == 0) + *acl = NULL; + if (!vfsgid_in_group_p(i_gid_into_vfsgid(idmap, inode)) && + !capable_wrt_inode_uidgid(idmap, inode, CAP_FSETID)) + mode &= ~S_ISGID; + *mode_p = mode; + return 0; +} + +static int __f2fs_set_acl(struct mnt_idmap *idmap, + struct inode *inode, int type, + struct posix_acl *acl, struct page *ipage) +{ + int name_index; + void *value = NULL; + size_t size = 0; + int error; + umode_t mode = inode->i_mode; + + switch (type) { + case ACL_TYPE_ACCESS: + name_index = F2FS_XATTR_INDEX_POSIX_ACL_ACCESS; + if (acl && !ipage) { + error = f2fs_acl_update_mode(idmap, inode, + &mode, &acl); + if (error) + return error; + set_acl_inode(inode, mode); + } + break; + + case ACL_TYPE_DEFAULT: + name_index = F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT; + if (!S_ISDIR(inode->i_mode)) + return acl ? -EACCES : 0; + break; + + default: + return -EINVAL; + } + + if (acl) { + value = f2fs_acl_to_disk(F2FS_I_SB(inode), acl, &size); + if (IS_ERR(value)) { + clear_inode_flag(inode, FI_ACL_MODE); + return PTR_ERR(value); + } + } + + error = f2fs_setxattr(inode, name_index, "", value, size, ipage, 0); + + kfree(value); + if (!error) + set_cached_acl(inode, type, acl); + + clear_inode_flag(inode, FI_ACL_MODE); + return error; +} + +int f2fs_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, + struct posix_acl *acl, int type) +{ + struct inode *inode = d_inode(dentry); + + if (unlikely(f2fs_cp_error(F2FS_I_SB(inode)))) + return -EIO; + + return __f2fs_set_acl(idmap, inode, type, acl, NULL); +} + +/* + * Most part of f2fs_acl_clone, f2fs_acl_create_masq, f2fs_acl_create + * are copied from posix_acl.c + */ +static struct posix_acl *f2fs_acl_clone(const struct posix_acl *acl, + gfp_t flags) +{ + struct posix_acl *clone = NULL; + + if (acl) { + int size = sizeof(struct posix_acl) + acl->a_count * + sizeof(struct posix_acl_entry); + clone = kmemdup(acl, size, flags); + if (clone) + refcount_set(&clone->a_refcount, 1); + } + return clone; +} + +static int f2fs_acl_create_masq(struct posix_acl *acl, umode_t *mode_p) +{ + struct posix_acl_entry *pa, *pe; + struct posix_acl_entry *group_obj = NULL, *mask_obj = NULL; + umode_t mode = *mode_p; + int not_equiv = 0; + + /* assert(atomic_read(acl->a_refcount) == 1); */ + + FOREACH_ACL_ENTRY(pa, acl, pe) { + switch (pa->e_tag) { + case ACL_USER_OBJ: + pa->e_perm &= (mode >> 6) | ~S_IRWXO; + mode &= (pa->e_perm << 6) | ~S_IRWXU; + break; + + case ACL_USER: + case ACL_GROUP: + not_equiv = 1; + break; + + case ACL_GROUP_OBJ: + group_obj = pa; + break; + + case ACL_OTHER: + pa->e_perm &= mode | ~S_IRWXO; + mode &= pa->e_perm | ~S_IRWXO; + break; + + case ACL_MASK: + mask_obj = pa; + not_equiv = 1; + break; + + default: + return -EIO; + } + } + + if (mask_obj) { + mask_obj->e_perm &= (mode >> 3) | ~S_IRWXO; + mode &= (mask_obj->e_perm << 3) | ~S_IRWXG; + } else { + if (!group_obj) + return -EIO; + group_obj->e_perm &= (mode >> 3) | ~S_IRWXO; + mode &= (group_obj->e_perm << 3) | ~S_IRWXG; + } + + *mode_p = (*mode_p & ~S_IRWXUGO) | mode; + return not_equiv; +} + +static int f2fs_acl_create(struct inode *dir, umode_t *mode, + struct posix_acl **default_acl, struct posix_acl **acl, + struct page *dpage) +{ + struct posix_acl *p; + struct posix_acl *clone; + int ret; + + *acl = NULL; + *default_acl = NULL; + + if (S_ISLNK(*mode) || !IS_POSIXACL(dir)) + return 0; + + p = __f2fs_get_acl(dir, ACL_TYPE_DEFAULT, dpage); + if (!p || p == ERR_PTR(-EOPNOTSUPP)) { + *mode &= ~current_umask(); + return 0; + } + if (IS_ERR(p)) + return PTR_ERR(p); + + clone = f2fs_acl_clone(p, GFP_NOFS); + if (!clone) { + ret = -ENOMEM; + goto release_acl; + } + + ret = f2fs_acl_create_masq(clone, mode); + if (ret < 0) + goto release_clone; + + if (ret == 0) + posix_acl_release(clone); + else + *acl = clone; + + if (!S_ISDIR(*mode)) + posix_acl_release(p); + else + *default_acl = p; + + return 0; + +release_clone: + posix_acl_release(clone); +release_acl: + posix_acl_release(p); + return ret; +} + +int f2fs_init_acl(struct inode *inode, struct inode *dir, struct page *ipage, + struct page *dpage) +{ + struct posix_acl *default_acl = NULL, *acl = NULL; + int error; + + error = f2fs_acl_create(dir, &inode->i_mode, &default_acl, &acl, dpage); + if (error) + return error; + + f2fs_mark_inode_dirty_sync(inode, true); + + if (default_acl) { + error = __f2fs_set_acl(NULL, inode, ACL_TYPE_DEFAULT, default_acl, + ipage); + posix_acl_release(default_acl); + } else { + inode->i_default_acl = NULL; + } + if (acl) { + if (!error) + error = __f2fs_set_acl(NULL, inode, ACL_TYPE_ACCESS, acl, + ipage); + posix_acl_release(acl); + } else { + inode->i_acl = NULL; + } + + return error; +} |