| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * |
| * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved. |
| * |
| */ |
| |
| #include <linux/fs.h> |
| |
| #include "debug.h" |
| #include "ntfs.h" |
| #include "ntfs_fs.h" |
| |
| /* |
| * al_is_valid_le |
| * |
| * Return: True if @le is valid. |
| */ |
| static inline bool al_is_valid_le(const struct ntfs_inode *ni, |
| struct ATTR_LIST_ENTRY *le) |
| { |
| if (!le || !ni->attr_list.le || !ni->attr_list.size) |
| return false; |
| |
| return PtrOffset(ni->attr_list.le, le) + le16_to_cpu(le->size) <= |
| ni->attr_list.size; |
| } |
| |
| void al_destroy(struct ntfs_inode *ni) |
| { |
| run_close(&ni->attr_list.run); |
| kfree(ni->attr_list.le); |
| ni->attr_list.le = NULL; |
| ni->attr_list.size = 0; |
| ni->attr_list.dirty = false; |
| } |
| |
| /* |
| * ntfs_load_attr_list |
| * |
| * This method makes sure that the ATTRIB list, if present, |
| * has been properly set up. |
| */ |
| int ntfs_load_attr_list(struct ntfs_inode *ni, struct ATTRIB *attr) |
| { |
| int err; |
| size_t lsize; |
| void *le = NULL; |
| |
| if (ni->attr_list.size) |
| return 0; |
| |
| if (!attr->non_res) { |
| lsize = le32_to_cpu(attr->res.data_size); |
| le = kmalloc(al_aligned(lsize), GFP_NOFS); |
| if (!le) { |
| err = -ENOMEM; |
| goto out; |
| } |
| memcpy(le, resident_data(attr), lsize); |
| } else if (attr->nres.svcn) { |
| err = -EINVAL; |
| goto out; |
| } else { |
| u16 run_off = le16_to_cpu(attr->nres.run_off); |
| |
| lsize = le64_to_cpu(attr->nres.data_size); |
| |
| run_init(&ni->attr_list.run); |
| |
| if (run_off > le32_to_cpu(attr->size)) { |
| err = -EINVAL; |
| goto out; |
| } |
| |
| err = run_unpack_ex(&ni->attr_list.run, ni->mi.sbi, ni->mi.rno, |
| 0, le64_to_cpu(attr->nres.evcn), 0, |
| Add2Ptr(attr, run_off), |
| le32_to_cpu(attr->size) - run_off); |
| if (err < 0) |
| goto out; |
| |
| le = kmalloc(al_aligned(lsize), GFP_NOFS); |
| if (!le) { |
| err = -ENOMEM; |
| goto out; |
| } |
| |
| err = ntfs_read_run_nb(ni->mi.sbi, &ni->attr_list.run, 0, le, |
| lsize, NULL); |
| if (err) |
| goto out; |
| } |
| |
| ni->attr_list.size = lsize; |
| ni->attr_list.le = le; |
| |
| return 0; |
| |
| out: |
| ni->attr_list.le = le; |
| al_destroy(ni); |
| |
| return err; |
| } |
| |
| /* |
| * al_enumerate |
| * |
| * Return: |
| * * The next list le. |
| * * If @le is NULL then return the first le. |
| */ |
| struct ATTR_LIST_ENTRY *al_enumerate(struct ntfs_inode *ni, |
| struct ATTR_LIST_ENTRY *le) |
| { |
| size_t off; |
| u16 sz; |
| |
| if (!le) { |
| le = ni->attr_list.le; |
| } else { |
| sz = le16_to_cpu(le->size); |
| if (sz < sizeof(struct ATTR_LIST_ENTRY)) { |
| /* Impossible 'cause we should not return such le. */ |
| return NULL; |
| } |
| le = Add2Ptr(le, sz); |
| } |
| |
| /* Check boundary. */ |
| off = PtrOffset(ni->attr_list.le, le); |
| if (off + sizeof(struct ATTR_LIST_ENTRY) > ni->attr_list.size) { |
| /* The regular end of list. */ |
| return NULL; |
| } |
| |
| sz = le16_to_cpu(le->size); |
| |
| /* Check le for errors. */ |
| if (sz < sizeof(struct ATTR_LIST_ENTRY) || |
| off + sz > ni->attr_list.size || |
| sz < le->name_off + le->name_len * sizeof(short)) { |
| return NULL; |
| } |
| |
| return le; |
| } |
| |
| /* |
| * al_find_le |
| * |
| * Find the first le in the list which matches type, name and VCN. |
| * |
| * Return: NULL if not found. |
| */ |
| struct ATTR_LIST_ENTRY *al_find_le(struct ntfs_inode *ni, |
| struct ATTR_LIST_ENTRY *le, |
| const struct ATTRIB *attr) |
| { |
| CLST svcn = attr_svcn(attr); |
| |
| return al_find_ex(ni, le, attr->type, attr_name(attr), attr->name_len, |
| &svcn); |
| } |
| |
| /* |
| * al_find_ex |
| * |
| * Find the first le in the list which matches type, name and VCN. |
| * |
| * Return: NULL if not found. |
| */ |
| struct ATTR_LIST_ENTRY *al_find_ex(struct ntfs_inode *ni, |
| struct ATTR_LIST_ENTRY *le, |
| enum ATTR_TYPE type, const __le16 *name, |
| u8 name_len, const CLST *vcn) |
| { |
| struct ATTR_LIST_ENTRY *ret = NULL; |
| u32 type_in = le32_to_cpu(type); |
| |
| while ((le = al_enumerate(ni, le))) { |
| u64 le_vcn; |
| int diff = le32_to_cpu(le->type) - type_in; |
| |
| /* List entries are sorted by type, name and VCN. */ |
| if (diff < 0) |
| continue; |
| |
| if (diff > 0) |
| return ret; |
| |
| if (le->name_len != name_len) |
| continue; |
| |
| le_vcn = le64_to_cpu(le->vcn); |
| if (!le_vcn) { |
| /* |
| * Compare entry names only for entry with vcn == 0. |
| */ |
| diff = ntfs_cmp_names(le_name(le), name_len, name, |
| name_len, ni->mi.sbi->upcase, |
| true); |
| if (diff < 0) |
| continue; |
| |
| if (diff > 0) |
| return ret; |
| } |
| |
| if (!vcn) |
| return le; |
| |
| if (*vcn == le_vcn) |
| return le; |
| |
| if (*vcn < le_vcn) |
| return ret; |
| |
| ret = le; |
| } |
| |
| return ret; |
| } |
| |
| /* |
| * al_find_le_to_insert |
| * |
| * Find the first list entry which matches type, name and VCN. |
| */ |
| static struct ATTR_LIST_ENTRY *al_find_le_to_insert(struct ntfs_inode *ni, |
| enum ATTR_TYPE type, |
| const __le16 *name, |
| u8 name_len, CLST vcn) |
| { |
| struct ATTR_LIST_ENTRY *le = NULL, *prev; |
| u32 type_in = le32_to_cpu(type); |
| |
| /* List entries are sorted by type, name and VCN. */ |
| while ((le = al_enumerate(ni, prev = le))) { |
| int diff = le32_to_cpu(le->type) - type_in; |
| |
| if (diff < 0) |
| continue; |
| |
| if (diff > 0) |
| return le; |
| |
| if (!le->vcn) { |
| /* |
| * Compare entry names only for entry with vcn == 0. |
| */ |
| diff = ntfs_cmp_names(le_name(le), le->name_len, name, |
| name_len, ni->mi.sbi->upcase, |
| true); |
| if (diff < 0) |
| continue; |
| |
| if (diff > 0) |
| return le; |
| } |
| |
| if (le64_to_cpu(le->vcn) >= vcn) |
| return le; |
| } |
| |
| return prev ? Add2Ptr(prev, le16_to_cpu(prev->size)) : ni->attr_list.le; |
| } |
| |
| /* |
| * al_add_le |
| * |
| * Add an "attribute list entry" to the list. |
| */ |
| int al_add_le(struct ntfs_inode *ni, enum ATTR_TYPE type, const __le16 *name, |
| u8 name_len, CLST svcn, __le16 id, const struct MFT_REF *ref, |
| struct ATTR_LIST_ENTRY **new_le) |
| { |
| int err; |
| struct ATTRIB *attr; |
| struct ATTR_LIST_ENTRY *le; |
| size_t off; |
| u16 sz; |
| size_t asize, new_asize, old_size; |
| u64 new_size; |
| typeof(ni->attr_list) *al = &ni->attr_list; |
| |
| /* |
| * Compute the size of the new 'le' |
| */ |
| sz = le_size(name_len); |
| old_size = al->size; |
| new_size = old_size + sz; |
| asize = al_aligned(old_size); |
| new_asize = al_aligned(new_size); |
| |
| /* Scan forward to the point at which the new 'le' should be inserted. */ |
| le = al_find_le_to_insert(ni, type, name, name_len, svcn); |
| off = PtrOffset(al->le, le); |
| |
| if (new_size > asize) { |
| void *ptr = kmalloc(new_asize, GFP_NOFS); |
| |
| if (!ptr) |
| return -ENOMEM; |
| |
| memcpy(ptr, al->le, off); |
| memcpy(Add2Ptr(ptr, off + sz), le, old_size - off); |
| le = Add2Ptr(ptr, off); |
| kfree(al->le); |
| al->le = ptr; |
| } else { |
| memmove(Add2Ptr(le, sz), le, old_size - off); |
| } |
| *new_le = le; |
| |
| al->size = new_size; |
| |
| le->type = type; |
| le->size = cpu_to_le16(sz); |
| le->name_len = name_len; |
| le->name_off = offsetof(struct ATTR_LIST_ENTRY, name); |
| le->vcn = cpu_to_le64(svcn); |
| le->ref = *ref; |
| le->id = id; |
| memcpy(le->name, name, sizeof(short) * name_len); |
| |
| err = attr_set_size(ni, ATTR_LIST, NULL, 0, &al->run, new_size, |
| &new_size, true, &attr); |
| if (err) { |
| /* Undo memmove above. */ |
| memmove(le, Add2Ptr(le, sz), old_size - off); |
| al->size = old_size; |
| return err; |
| } |
| |
| al->dirty = true; |
| |
| if (attr && attr->non_res) { |
| err = ntfs_sb_write_run(ni->mi.sbi, &al->run, 0, al->le, |
| al->size, 0); |
| if (err) |
| return err; |
| al->dirty = false; |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * al_remove_le - Remove @le from attribute list. |
| */ |
| bool al_remove_le(struct ntfs_inode *ni, struct ATTR_LIST_ENTRY *le) |
| { |
| u16 size; |
| size_t off; |
| typeof(ni->attr_list) *al = &ni->attr_list; |
| |
| if (!al_is_valid_le(ni, le)) |
| return false; |
| |
| /* Save on stack the size of 'le' */ |
| size = le16_to_cpu(le->size); |
| off = PtrOffset(al->le, le); |
| |
| memmove(le, Add2Ptr(le, size), al->size - (off + size)); |
| |
| al->size -= size; |
| al->dirty = true; |
| |
| return true; |
| } |
| |
| /* |
| * al_delete_le - Delete first le from the list which matches its parameters. |
| */ |
| bool al_delete_le(struct ntfs_inode *ni, enum ATTR_TYPE type, CLST vcn, |
| const __le16 *name, size_t name_len, |
| const struct MFT_REF *ref) |
| { |
| u16 size; |
| struct ATTR_LIST_ENTRY *le; |
| size_t off; |
| typeof(ni->attr_list) *al = &ni->attr_list; |
| |
| /* Scan forward to the first le that matches the input. */ |
| le = al_find_ex(ni, NULL, type, name, name_len, &vcn); |
| if (!le) |
| return false; |
| |
| off = PtrOffset(al->le, le); |
| |
| next: |
| if (off >= al->size) |
| return false; |
| if (le->type != type) |
| return false; |
| if (le->name_len != name_len) |
| return false; |
| if (name_len && ntfs_cmp_names(le_name(le), name_len, name, name_len, |
| ni->mi.sbi->upcase, true)) |
| return false; |
| if (le64_to_cpu(le->vcn) != vcn) |
| return false; |
| |
| /* |
| * The caller specified a segment reference, so we have to |
| * scan through the matching entries until we find that segment |
| * reference or we run of matching entries. |
| */ |
| if (ref && memcmp(ref, &le->ref, sizeof(*ref))) { |
| off += le16_to_cpu(le->size); |
| le = Add2Ptr(al->le, off); |
| goto next; |
| } |
| |
| /* Save on stack the size of 'le'. */ |
| size = le16_to_cpu(le->size); |
| /* Delete the le. */ |
| memmove(le, Add2Ptr(le, size), al->size - (off + size)); |
| |
| al->size -= size; |
| al->dirty = true; |
| |
| return true; |
| } |
| |
| int al_update(struct ntfs_inode *ni, int sync) |
| { |
| int err; |
| struct ATTRIB *attr; |
| typeof(ni->attr_list) *al = &ni->attr_list; |
| |
| if (!al->dirty || !al->size) |
| return 0; |
| |
| /* |
| * Attribute list increased on demand in al_add_le. |
| * Attribute list decreased here. |
| */ |
| err = attr_set_size(ni, ATTR_LIST, NULL, 0, &al->run, al->size, NULL, |
| false, &attr); |
| if (err) |
| goto out; |
| |
| if (!attr->non_res) { |
| memcpy(resident_data(attr), al->le, al->size); |
| } else { |
| err = ntfs_sb_write_run(ni->mi.sbi, &al->run, 0, al->le, |
| al->size, sync); |
| if (err) |
| goto out; |
| |
| attr->nres.valid_size = attr->nres.data_size; |
| } |
| |
| ni->mi.dirty = true; |
| al->dirty = false; |
| |
| out: |
| return err; |
| } |