diff options
Diffstat (limited to 'fs/f2fs/xattr.c')
| -rw-r--r-- | fs/f2fs/xattr.c | 770 |
1 files changed, 770 insertions, 0 deletions
diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c new file mode 100644 index 000000000..64352d283 --- /dev/null +++ b/fs/f2fs/xattr.c @@ -0,0 +1,770 @@ +/* + * fs/f2fs/xattr.c + * + * Copyright (c) 2012 Samsung Electronics Co., Ltd. + * http://www.samsung.com/ + * + * Portions of this code from linux/fs/ext2/xattr.c + * + * Copyright (C) 2001-2003 Andreas Gruenbacher <agruen@suse.de> + * + * Fix by Harrison Xing <harrison@mountainviewdata.com>. + * Extended attributes for symlinks and special files added per + * suggestion of Luka Renko <luka.renko@hermes.si>. + * xattr consolidation Copyright (c) 2004 James Morris <jmorris@redhat.com>, + * Red Hat Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/rwsem.h> +#include <linux/f2fs_fs.h> +#include <linux/security.h> +#include <linux/posix_acl_xattr.h> +#include "f2fs.h" +#include "xattr.h" + +static int f2fs_xattr_generic_get(const struct xattr_handler *handler, + struct dentry *unused, struct inode *inode, + const char *name, void *buffer, size_t size) +{ + struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb); + + switch (handler->flags) { + case F2FS_XATTR_INDEX_USER: + if (!test_opt(sbi, XATTR_USER)) + return -EOPNOTSUPP; + break; + case F2FS_XATTR_INDEX_TRUSTED: + case F2FS_XATTR_INDEX_SECURITY: + break; + default: + return -EINVAL; + } + return f2fs_getxattr(inode, handler->flags, name, + buffer, size, NULL); +} + +static int f2fs_xattr_generic_set(const struct xattr_handler *handler, + struct dentry *unused, struct inode *inode, + const char *name, const void *value, + size_t size, int flags) +{ + struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb); + + switch (handler->flags) { + case F2FS_XATTR_INDEX_USER: + if (!test_opt(sbi, XATTR_USER)) + return -EOPNOTSUPP; + break; + case F2FS_XATTR_INDEX_TRUSTED: + case F2FS_XATTR_INDEX_SECURITY: + break; + default: + return -EINVAL; + } + return f2fs_setxattr(inode, handler->flags, name, + value, size, NULL, flags); +} + +static bool f2fs_xattr_user_list(struct dentry *dentry) +{ + struct f2fs_sb_info *sbi = F2FS_SB(dentry->d_sb); + + return test_opt(sbi, XATTR_USER); +} + +static bool f2fs_xattr_trusted_list(struct dentry *dentry) +{ + return capable(CAP_SYS_ADMIN); +} + +static int f2fs_xattr_advise_get(const struct xattr_handler *handler, + struct dentry *unused, struct inode *inode, + const char *name, void *buffer, size_t size) +{ + if (buffer) + *((char *)buffer) = F2FS_I(inode)->i_advise; + return sizeof(char); +} + +static int f2fs_xattr_advise_set(const struct xattr_handler *handler, + struct dentry *unused, struct inode *inode, + const char *name, const void *value, + size_t size, int flags) +{ + unsigned char old_advise = F2FS_I(inode)->i_advise; + unsigned char new_advise; + + if (!inode_owner_or_capable(inode)) + return -EPERM; + if (value == NULL) + return -EINVAL; + + new_advise = *(char *)value; + if (new_advise & ~FADVISE_MODIFIABLE_BITS) + return -EINVAL; + + new_advise = new_advise & FADVISE_MODIFIABLE_BITS; + new_advise |= old_advise & ~FADVISE_MODIFIABLE_BITS; + + F2FS_I(inode)->i_advise = new_advise; + f2fs_mark_inode_dirty_sync(inode, true); + return 0; +} + +#ifdef CONFIG_F2FS_FS_SECURITY +static int f2fs_initxattrs(struct inode *inode, const struct xattr *xattr_array, + void *page) +{ + const struct xattr *xattr; + int err = 0; + + for (xattr = xattr_array; xattr->name != NULL; xattr++) { + err = f2fs_setxattr(inode, F2FS_XATTR_INDEX_SECURITY, + xattr->name, xattr->value, + xattr->value_len, (struct page *)page, 0); + if (err < 0) + break; + } + return err; +} + +int f2fs_init_security(struct inode *inode, struct inode *dir, + const struct qstr *qstr, struct page *ipage) +{ + return security_inode_init_security(inode, dir, qstr, + &f2fs_initxattrs, ipage); +} +#endif + +const struct xattr_handler f2fs_xattr_user_handler = { + .prefix = XATTR_USER_PREFIX, + .flags = F2FS_XATTR_INDEX_USER, + .list = f2fs_xattr_user_list, + .get = f2fs_xattr_generic_get, + .set = f2fs_xattr_generic_set, +}; + +const struct xattr_handler f2fs_xattr_trusted_handler = { + .prefix = XATTR_TRUSTED_PREFIX, + .flags = F2FS_XATTR_INDEX_TRUSTED, + .list = f2fs_xattr_trusted_list, + .get = f2fs_xattr_generic_get, + .set = f2fs_xattr_generic_set, +}; + +const struct xattr_handler f2fs_xattr_advise_handler = { + .name = F2FS_SYSTEM_ADVISE_NAME, + .flags = F2FS_XATTR_INDEX_ADVISE, + .get = f2fs_xattr_advise_get, + .set = f2fs_xattr_advise_set, +}; + +const struct xattr_handler f2fs_xattr_security_handler = { + .prefix = XATTR_SECURITY_PREFIX, + .flags = F2FS_XATTR_INDEX_SECURITY, + .get = f2fs_xattr_generic_get, + .set = f2fs_xattr_generic_set, +}; + +static const struct xattr_handler *f2fs_xattr_handler_map[] = { + [F2FS_XATTR_INDEX_USER] = &f2fs_xattr_user_handler, +#ifdef CONFIG_F2FS_FS_POSIX_ACL + [F2FS_XATTR_INDEX_POSIX_ACL_ACCESS] = &posix_acl_access_xattr_handler, + [F2FS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &posix_acl_default_xattr_handler, +#endif + [F2FS_XATTR_INDEX_TRUSTED] = &f2fs_xattr_trusted_handler, +#ifdef CONFIG_F2FS_FS_SECURITY + [F2FS_XATTR_INDEX_SECURITY] = &f2fs_xattr_security_handler, +#endif + [F2FS_XATTR_INDEX_ADVISE] = &f2fs_xattr_advise_handler, +}; + +const struct xattr_handler *f2fs_xattr_handlers[] = { + &f2fs_xattr_user_handler, +#ifdef CONFIG_F2FS_FS_POSIX_ACL + &posix_acl_access_xattr_handler, + &posix_acl_default_xattr_handler, +#endif + &f2fs_xattr_trusted_handler, +#ifdef CONFIG_F2FS_FS_SECURITY + &f2fs_xattr_security_handler, +#endif + &f2fs_xattr_advise_handler, + NULL, +}; + +static inline const struct xattr_handler *f2fs_xattr_handler(int index) +{ + const struct xattr_handler *handler = NULL; + + if (index > 0 && index < ARRAY_SIZE(f2fs_xattr_handler_map)) + handler = f2fs_xattr_handler_map[index]; + return handler; +} + +static struct f2fs_xattr_entry *__find_xattr(void *base_addr, + void *last_base_addr, int index, + size_t len, const char *name) +{ + struct f2fs_xattr_entry *entry; + + list_for_each_xattr(entry, base_addr) { + if ((void *)(entry) + sizeof(__u32) > last_base_addr || + (void *)XATTR_NEXT_ENTRY(entry) > last_base_addr) + return NULL; + + if (entry->e_name_index != index) + continue; + if (entry->e_name_len != len) + continue; + if (!memcmp(entry->e_name, name, len)) + break; + } + return entry; +} + +static struct f2fs_xattr_entry *__find_inline_xattr(struct inode *inode, + void *base_addr, void **last_addr, int index, + size_t len, const char *name) +{ + struct f2fs_xattr_entry *entry; + unsigned int inline_size = inline_xattr_size(inode); + void *max_addr = base_addr + inline_size; + + list_for_each_xattr(entry, base_addr) { + if ((void *)entry + sizeof(__u32) > max_addr || + (void *)XATTR_NEXT_ENTRY(entry) > max_addr) { + *last_addr = entry; + return NULL; + } + if (entry->e_name_index != index) + continue; + if (entry->e_name_len != len) + continue; + if (!memcmp(entry->e_name, name, len)) + break; + } + + /* inline xattr header or entry across max inline xattr size */ + if (IS_XATTR_LAST_ENTRY(entry) && + (void *)entry + sizeof(__u32) > max_addr) { + *last_addr = entry; + return NULL; + } + return entry; +} + +static int read_inline_xattr(struct inode *inode, struct page *ipage, + void *txattr_addr) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + unsigned int inline_size = inline_xattr_size(inode); + struct page *page = NULL; + void *inline_addr; + + if (ipage) { + inline_addr = inline_xattr_addr(inode, ipage); + } else { + page = f2fs_get_node_page(sbi, inode->i_ino); + if (IS_ERR(page)) + return PTR_ERR(page); + + inline_addr = inline_xattr_addr(inode, page); + } + memcpy(txattr_addr, inline_addr, inline_size); + f2fs_put_page(page, 1); + + return 0; +} + +static int read_xattr_block(struct inode *inode, void *txattr_addr) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + nid_t xnid = F2FS_I(inode)->i_xattr_nid; + unsigned int inline_size = inline_xattr_size(inode); + struct page *xpage; + void *xattr_addr; + + /* The inode already has an extended attribute block. */ + xpage = f2fs_get_node_page(sbi, xnid); + if (IS_ERR(xpage)) + return PTR_ERR(xpage); + + xattr_addr = page_address(xpage); + memcpy(txattr_addr + inline_size, xattr_addr, VALID_XATTR_BLOCK_SIZE); + f2fs_put_page(xpage, 1); + + return 0; +} + +static int lookup_all_xattrs(struct inode *inode, struct page *ipage, + unsigned int index, unsigned int len, + const char *name, struct f2fs_xattr_entry **xe, + void **base_addr, int *base_size) +{ + void *cur_addr, *txattr_addr, *last_txattr_addr; + void *last_addr = NULL; + nid_t xnid = F2FS_I(inode)->i_xattr_nid; + unsigned int inline_size = inline_xattr_size(inode); + int err = 0; + + if (!xnid && !inline_size) + return -ENODATA; + + *base_size = XATTR_SIZE(xnid, inode) + XATTR_PADDING_SIZE; + txattr_addr = f2fs_kzalloc(F2FS_I_SB(inode), *base_size, GFP_NOFS); + if (!txattr_addr) + return -ENOMEM; + + last_txattr_addr = (void *)txattr_addr + XATTR_SIZE(xnid, inode); + + /* read from inline xattr */ + if (inline_size) { + err = read_inline_xattr(inode, ipage, txattr_addr); + if (err) + goto out; + + *xe = __find_inline_xattr(inode, txattr_addr, &last_addr, + index, len, name); + if (*xe) { + *base_size = inline_size; + goto check; + } + } + + /* read from xattr node block */ + if (xnid) { + err = read_xattr_block(inode, txattr_addr); + if (err) + goto out; + } + + if (last_addr) + cur_addr = XATTR_HDR(last_addr) - 1; + else + cur_addr = txattr_addr; + + *xe = __find_xattr(cur_addr, last_txattr_addr, index, len, name); + if (!*xe) { + err = -EFSCORRUPTED; + goto out; + } +check: + if (IS_XATTR_LAST_ENTRY(*xe)) { + err = -ENODATA; + goto out; + } + + *base_addr = txattr_addr; + return 0; +out: + kzfree(txattr_addr); + return err; +} + +static int read_all_xattrs(struct inode *inode, struct page *ipage, + void **base_addr) +{ + struct f2fs_xattr_header *header; + nid_t xnid = F2FS_I(inode)->i_xattr_nid; + unsigned int size = VALID_XATTR_BLOCK_SIZE; + unsigned int inline_size = inline_xattr_size(inode); + void *txattr_addr; + int err; + + txattr_addr = f2fs_kzalloc(F2FS_I_SB(inode), + inline_size + size + XATTR_PADDING_SIZE, GFP_NOFS); + if (!txattr_addr) + return -ENOMEM; + + /* read from inline xattr */ + if (inline_size) { + err = read_inline_xattr(inode, ipage, txattr_addr); + if (err) + goto fail; + } + + /* read from xattr node block */ + if (xnid) { + err = read_xattr_block(inode, txattr_addr); + if (err) + goto fail; + } + + header = XATTR_HDR(txattr_addr); + + /* never been allocated xattrs */ + if (le32_to_cpu(header->h_magic) != F2FS_XATTR_MAGIC) { + header->h_magic = cpu_to_le32(F2FS_XATTR_MAGIC); + header->h_refcount = cpu_to_le32(1); + } + *base_addr = txattr_addr; + return 0; +fail: + kzfree(txattr_addr); + return err; +} + +static inline int write_all_xattrs(struct inode *inode, __u32 hsize, + void *txattr_addr, struct page *ipage) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + size_t inline_size = inline_xattr_size(inode); + struct page *in_page = NULL; + void *xattr_addr; + void *inline_addr = NULL; + struct page *xpage; + nid_t new_nid = 0; + int err = 0; + + if (hsize > inline_size && !F2FS_I(inode)->i_xattr_nid) + if (!f2fs_alloc_nid(sbi, &new_nid)) + return -ENOSPC; + + /* write to inline xattr */ + if (inline_size) { + if (ipage) { + inline_addr = inline_xattr_addr(inode, ipage); + } else { + in_page = f2fs_get_node_page(sbi, inode->i_ino); + if (IS_ERR(in_page)) { + f2fs_alloc_nid_failed(sbi, new_nid); + return PTR_ERR(in_page); + } + inline_addr = inline_xattr_addr(inode, in_page); + } + + f2fs_wait_on_page_writeback(ipage ? ipage : in_page, + NODE, true); + /* no need to use xattr node block */ + if (hsize <= inline_size) { + err = f2fs_truncate_xattr_node(inode); + f2fs_alloc_nid_failed(sbi, new_nid); + if (err) { + f2fs_put_page(in_page, 1); + return err; + } + memcpy(inline_addr, txattr_addr, inline_size); + set_page_dirty(ipage ? ipage : in_page); + goto in_page_out; + } + } + + /* write to xattr node block */ + if (F2FS_I(inode)->i_xattr_nid) { + xpage = f2fs_get_node_page(sbi, F2FS_I(inode)->i_xattr_nid); + if (IS_ERR(xpage)) { + err = PTR_ERR(xpage); + f2fs_alloc_nid_failed(sbi, new_nid); + goto in_page_out; + } + f2fs_bug_on(sbi, new_nid); + f2fs_wait_on_page_writeback(xpage, NODE, true); + } else { + struct dnode_of_data dn; + set_new_dnode(&dn, inode, NULL, NULL, new_nid); + xpage = f2fs_new_node_page(&dn, XATTR_NODE_OFFSET); + if (IS_ERR(xpage)) { + err = PTR_ERR(xpage); + f2fs_alloc_nid_failed(sbi, new_nid); + goto in_page_out; + } + f2fs_alloc_nid_done(sbi, new_nid); + } + xattr_addr = page_address(xpage); + + if (inline_size) + memcpy(inline_addr, txattr_addr, inline_size); + memcpy(xattr_addr, txattr_addr + inline_size, VALID_XATTR_BLOCK_SIZE); + + if (inline_size) + set_page_dirty(ipage ? ipage : in_page); + set_page_dirty(xpage); + + f2fs_put_page(xpage, 1); +in_page_out: + f2fs_put_page(in_page, 1); + return err; +} + +int f2fs_getxattr(struct inode *inode, int index, const char *name, + void *buffer, size_t buffer_size, struct page *ipage) +{ + struct f2fs_xattr_entry *entry = NULL; + int error = 0; + unsigned int size, len; + void *base_addr = NULL; + int base_size; + + if (name == NULL) + return -EINVAL; + + len = strlen(name); + if (len > F2FS_NAME_LEN) + return -ERANGE; + + down_read(&F2FS_I(inode)->i_xattr_sem); + error = lookup_all_xattrs(inode, ipage, index, len, name, + &entry, &base_addr, &base_size); + up_read(&F2FS_I(inode)->i_xattr_sem); + if (error) + return error; + + size = le16_to_cpu(entry->e_value_size); + + if (buffer && size > buffer_size) { + error = -ERANGE; + goto out; + } + + if (buffer) { + char *pval = entry->e_name + entry->e_name_len; + + if (base_size - (pval - (char *)base_addr) < size) { + error = -ERANGE; + goto out; + } + memcpy(buffer, pval, size); + } + error = size; +out: + kzfree(base_addr); + return error; +} + +ssize_t f2fs_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) +{ + struct inode *inode = d_inode(dentry); + nid_t xnid = F2FS_I(inode)->i_xattr_nid; + struct f2fs_xattr_entry *entry; + void *base_addr, *last_base_addr; + int error = 0; + size_t rest = buffer_size; + + down_read(&F2FS_I(inode)->i_xattr_sem); + error = read_all_xattrs(inode, NULL, &base_addr); + up_read(&F2FS_I(inode)->i_xattr_sem); + if (error) + return error; + + last_base_addr = (void *)base_addr + XATTR_SIZE(xnid, inode); + + list_for_each_xattr(entry, base_addr) { + const struct xattr_handler *handler = + f2fs_xattr_handler(entry->e_name_index); + const char *prefix; + size_t prefix_len; + size_t size; + + if ((void *)(entry) + sizeof(__u32) > last_base_addr || + (void *)XATTR_NEXT_ENTRY(entry) > last_base_addr) { + f2fs_msg(dentry->d_sb, KERN_ERR, + "inode (%lu) has corrupted xattr", + inode->i_ino); + set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK); + error = -EFSCORRUPTED; + goto cleanup; + } + + if (!handler || (handler->list && !handler->list(dentry))) + continue; + + prefix = handler->prefix ?: handler->name; + prefix_len = strlen(prefix); + size = prefix_len + entry->e_name_len + 1; + if (buffer) { + if (size > rest) { + error = -ERANGE; + goto cleanup; + } + memcpy(buffer, prefix, prefix_len); + buffer += prefix_len; + memcpy(buffer, entry->e_name, entry->e_name_len); + buffer += entry->e_name_len; + *buffer++ = 0; + } + rest -= size; + } + error = buffer_size - rest; +cleanup: + kzfree(base_addr); + return error; +} + +static bool f2fs_xattr_value_same(struct f2fs_xattr_entry *entry, + const void *value, size_t size) +{ + void *pval = entry->e_name + entry->e_name_len; + + return (le16_to_cpu(entry->e_value_size) == size) && + !memcmp(pval, value, size); +} + +static int __f2fs_setxattr(struct inode *inode, int index, + const char *name, const void *value, size_t size, + struct page *ipage, int flags) +{ + struct f2fs_xattr_entry *here, *last; + void *base_addr, *last_base_addr; + nid_t xnid = F2FS_I(inode)->i_xattr_nid; + int found, newsize; + size_t len; + __u32 new_hsize; + int error = 0; + + if (name == NULL) + return -EINVAL; + + if (value == NULL) + size = 0; + + len = strlen(name); + + if (len > F2FS_NAME_LEN) + return -ERANGE; + + if (size > MAX_VALUE_LEN(inode)) + return -E2BIG; + + error = read_all_xattrs(inode, ipage, &base_addr); + if (error) + return error; + + last_base_addr = (void *)base_addr + XATTR_SIZE(xnid, inode); + + /* find entry with wanted name. */ + here = __find_xattr(base_addr, last_base_addr, index, len, name); + if (!here) { + error = -EFSCORRUPTED; + goto exit; + } + + found = IS_XATTR_LAST_ENTRY(here) ? 0 : 1; + + if (found) { + if ((flags & XATTR_CREATE)) { + error = -EEXIST; + goto exit; + } + + if (value && f2fs_xattr_value_same(here, value, size)) + goto exit; + } else if ((flags & XATTR_REPLACE)) { + error = -ENODATA; + goto exit; + } + + last = here; + while (!IS_XATTR_LAST_ENTRY(last)) { + if ((void *)(last) + sizeof(__u32) > last_base_addr || + (void *)XATTR_NEXT_ENTRY(last) > last_base_addr) { + set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_FSCK); + error = -EFSCORRUPTED; + goto exit; + } + last = XATTR_NEXT_ENTRY(last); + } + + newsize = XATTR_ALIGN(sizeof(struct f2fs_xattr_entry) + len + size); + + /* 1. Check space */ + if (value) { + int free; + /* + * If value is NULL, it is remove operation. + * In case of update operation, we calculate free. + */ + free = MIN_OFFSET(inode) - ((char *)last - (char *)base_addr); + if (found) + free = free + ENTRY_SIZE(here); + + if (unlikely(free < newsize)) { + error = -E2BIG; + goto exit; + } + } + + /* 2. Remove old entry */ + if (found) { + /* + * If entry is found, remove old entry. + * If not found, remove operation is not needed. + */ + struct f2fs_xattr_entry *next = XATTR_NEXT_ENTRY(here); + int oldsize = ENTRY_SIZE(here); + + memmove(here, next, (char *)last - (char *)next); + last = (struct f2fs_xattr_entry *)((char *)last - oldsize); + memset(last, 0, oldsize); + } + + new_hsize = (char *)last - (char *)base_addr; + + /* 3. Write new entry */ + if (value) { + char *pval; + /* + * Before we come here, old entry is removed. + * We just write new entry. + */ + last->e_name_index = index; + last->e_name_len = len; + memcpy(last->e_name, name, len); + pval = last->e_name + len; + memcpy(pval, value, size); + last->e_value_size = cpu_to_le16(size); + new_hsize += newsize; + } + + error = write_all_xattrs(inode, new_hsize, base_addr, ipage); + if (error) + goto exit; + + if (is_inode_flag_set(inode, FI_ACL_MODE)) { + inode->i_mode = F2FS_I(inode)->i_acl_mode; + inode->i_ctime = current_time(inode); + clear_inode_flag(inode, FI_ACL_MODE); + } + if (index == F2FS_XATTR_INDEX_ENCRYPTION && + !strcmp(name, F2FS_XATTR_NAME_ENCRYPTION_CONTEXT)) + f2fs_set_encrypted_inode(inode); + f2fs_mark_inode_dirty_sync(inode, true); + if (!error && S_ISDIR(inode->i_mode)) + set_sbi_flag(F2FS_I_SB(inode), SBI_NEED_CP); +exit: + kzfree(base_addr); + return error; +} + +int f2fs_setxattr(struct inode *inode, int index, const char *name, + const void *value, size_t size, + struct page *ipage, int flags) +{ + struct f2fs_sb_info *sbi = F2FS_I_SB(inode); + int err; + + err = dquot_initialize(inode); + if (err) + return err; + + /* this case is only from f2fs_init_inode_metadata */ + if (ipage) + return __f2fs_setxattr(inode, index, name, value, + size, ipage, flags); + f2fs_balance_fs(sbi, true); + + f2fs_lock_op(sbi); + /* protect xattr_ver */ + down_write(&F2FS_I(inode)->i_sem); + down_write(&F2FS_I(inode)->i_xattr_sem); + err = __f2fs_setxattr(inode, index, name, value, size, ipage, flags); + up_write(&F2FS_I(inode)->i_xattr_sem); + up_write(&F2FS_I(inode)->i_sem); + f2fs_unlock_op(sbi); + + f2fs_update_time(sbi, REQ_TIME); + return err; +} |