// 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" static inline int compare_attr(const struct ATTRIB *left, enum ATTR_TYPE type, const __le16 *name, u8 name_len, const u16 *upcase) { /* First, compare the type codes. */ int diff = le32_to_cpu(left->type) - le32_to_cpu(type); if (diff) return diff; /* They have the same type code, so we have to compare the names. */ return ntfs_cmp_names(attr_name(left), left->name_len, name, name_len, upcase, true); } /* * mi_new_attt_id * * Return: Unused attribute id that is less than mrec->next_attr_id. */ static __le16 mi_new_attt_id(struct mft_inode *mi) { u16 free_id, max_id, t16; struct MFT_REC *rec = mi->mrec; struct ATTRIB *attr; __le16 id; id = rec->next_attr_id; free_id = le16_to_cpu(id); if (free_id < 0x7FFF) { rec->next_attr_id = cpu_to_le16(free_id + 1); return id; } /* One record can store up to 1024/24 ~= 42 attributes. */ free_id = 0; max_id = 0; attr = NULL; for (;;) { attr = mi_enum_attr(mi, attr); if (!attr) { rec->next_attr_id = cpu_to_le16(max_id + 1); mi->dirty = true; return cpu_to_le16(free_id); } t16 = le16_to_cpu(attr->id); if (t16 == free_id) { free_id += 1; attr = NULL; } else if (max_id < t16) max_id = t16; } } int mi_get(struct ntfs_sb_info *sbi, CLST rno, struct mft_inode **mi) { int err; struct mft_inode *m = kzalloc(sizeof(struct mft_inode), GFP_NOFS); if (!m) return -ENOMEM; err = mi_init(m, sbi, rno); if (err) { kfree(m); return err; } err = mi_read(m, false); if (err) { mi_put(m); return err; } *mi = m; return 0; } void mi_put(struct mft_inode *mi) { mi_clear(mi); kfree(mi); } int mi_init(struct mft_inode *mi, struct ntfs_sb_info *sbi, CLST rno) { mi->sbi = sbi; mi->rno = rno; mi->mrec = kmalloc(sbi->record_size, GFP_NOFS); if (!mi->mrec) return -ENOMEM; return 0; } /* * mi_read - Read MFT data. */ int mi_read(struct mft_inode *mi, bool is_mft) { int err; struct MFT_REC *rec = mi->mrec; struct ntfs_sb_info *sbi = mi->sbi; u32 bpr = sbi->record_size; u64 vbo = (u64)mi->rno << sbi->record_bits; struct ntfs_inode *mft_ni = sbi->mft.ni; struct runs_tree *run = mft_ni ? &mft_ni->file.run : NULL; struct rw_semaphore *rw_lock = NULL; if (is_mounted(sbi)) { if (!is_mft && mft_ni) { rw_lock = &mft_ni->file.run_lock; down_read(rw_lock); } } err = ntfs_read_bh(sbi, run, vbo, &rec->rhdr, bpr, &mi->nb); if (rw_lock) up_read(rw_lock); if (!err) goto ok; if (err == -E_NTFS_FIXUP) { mi->dirty = true; goto ok; } if (err != -ENOENT) goto out; if (rw_lock) { ni_lock(mft_ni); down_write(rw_lock); } err = attr_load_runs_vcn(mft_ni, ATTR_DATA, NULL, 0, run, vbo >> sbi->cluster_bits); if (rw_lock) { up_write(rw_lock); ni_unlock(mft_ni); } if (err) goto out; if (rw_lock) down_read(rw_lock); err = ntfs_read_bh(sbi, run, vbo, &rec->rhdr, bpr, &mi->nb); if (rw_lock) up_read(rw_lock); if (err == -E_NTFS_FIXUP) { mi->dirty = true; goto ok; } if (err) goto out; ok: /* Check field 'total' only here. */ if (le32_to_cpu(rec->total) != bpr) { err = -EINVAL; goto out; } return 0; out: if (err == -E_NTFS_CORRUPT) { ntfs_err(sbi->sb, "mft corrupted"); ntfs_set_state(sbi, NTFS_DIRTY_ERROR); err = -EINVAL; } return err; } /* * mi_enum_attr - start/continue attributes enumeration in record. * * NOTE: mi->mrec - memory of size sbi->record_size * here we sure that mi->mrec->total == sbi->record_size (see mi_read) */ struct ATTRIB *mi_enum_attr(struct mft_inode *mi, struct ATTRIB *attr) { const struct MFT_REC *rec = mi->mrec; u32 used = le32_to_cpu(rec->used); u32 t32, off, asize, prev_type; u16 t16; u64 data_size, alloc_size, tot_size; if (!attr) { u32 total = le32_to_cpu(rec->total); off = le16_to_cpu(rec->attr_off); if (used > total) return NULL; if (off >= used || off < MFTRECORD_FIXUP_OFFSET_1 || !IS_ALIGNED(off, 4)) { return NULL; } /* Skip non-resident records. */ if (!is_rec_inuse(rec)) return NULL; prev_type = 0; attr = Add2Ptr(rec, off); } else { /* Check if input attr inside record. */ off = PtrOffset(rec, attr); if (off >= used) return NULL; asize = le32_to_cpu(attr->size); if (asize < SIZEOF_RESIDENT) { /* Impossible 'cause we should not return such attribute. */ return NULL; } /* Overflow check. */ if (off + asize < off) return NULL; prev_type = le32_to_cpu(attr->type); attr = Add2Ptr(attr, asize); off += asize; } asize = le32_to_cpu(attr->size); /* Can we use the first field (attr->type). */ if (off + 8 > used) { static_assert(ALIGN(sizeof(enum ATTR_TYPE), 8) == 8); return NULL; } if (attr->type == ATTR_END) { /* End of enumeration. */ return NULL; } /* 0x100 is last known attribute for now. */ t32 = le32_to_cpu(attr->type); if (!t32 || (t32 & 0xf) || (t32 > 0x100)) return NULL; /* attributes in record must be ordered by type */ if (t32 < prev_type) return NULL; /* Check overflow and boundary. */ if (off + asize < off || off + asize > used) return NULL; /* Check size of attribute. */ if (!attr->non_res) { /* Check resident fields. */ if (asize < SIZEOF_RESIDENT) return NULL; t16 = le16_to_cpu(attr->res.data_off); if (t16 > asize) return NULL; if (le32_to_cpu(attr->res.data_size) > asize - t16) return NULL; t32 = sizeof(short) * attr->name_len; if (t32 && le16_to_cpu(attr->name_off) + t32 > t16) return NULL; return attr; } /* Check nonresident fields. */ if (attr->non_res != 1) return NULL; t16 = le16_to_cpu(attr->nres.run_off); if (t16 > asize) return NULL; t32 = sizeof(short) * attr->name_len; if (t32 && le16_to_cpu(attr->name_off) + t32 > t16) return NULL; /* Check start/end vcn. */ if (le64_to_cpu(attr->nres.svcn) > le64_to_cpu(attr->nres.evcn) + 1) return NULL; data_size = le64_to_cpu(attr->nres.data_size); if (le64_to_cpu(attr->nres.valid_size) > data_size) return NULL; alloc_size = le64_to_cpu(attr->nres.alloc_size); if (data_size > alloc_size) return NULL; t32 = mi->sbi->cluster_mask; if (alloc_size & t32) return NULL; if (!attr->nres.svcn && is_attr_ext(attr)) { /* First segment of sparse/compressed attribute */ if (asize + 8 < SIZEOF_NONRESIDENT_EX) return NULL; tot_size = le64_to_cpu(attr->nres.total_size); if (tot_size & t32) return NULL; if (tot_size > alloc_size) return NULL; } else { if (asize + 8 < SIZEOF_NONRESIDENT) return NULL; if (attr->nres.c_unit) return NULL; } return attr; } /* * mi_find_attr - Find the attribute by type and name and id. */ struct ATTRIB *mi_find_attr(struct mft_inode *mi, struct ATTRIB *attr, enum ATTR_TYPE type, const __le16 *name, u8 name_len, const __le16 *id) { u32 type_in = le32_to_cpu(type); u32 atype; next_attr: attr = mi_enum_attr(mi, attr); if (!attr) return NULL; atype = le32_to_cpu(attr->type); if (atype > type_in) return NULL; if (atype < type_in) goto next_attr; if (attr->name_len != name_len) goto next_attr; if (name_len && memcmp(attr_name(attr), name, name_len * sizeof(short))) goto next_attr; if (id && *id != attr->id) goto next_attr; return attr; } int mi_write(struct mft_inode *mi, int wait) { struct MFT_REC *rec; int err; struct ntfs_sb_info *sbi; if (!mi->dirty) return 0; sbi = mi->sbi; rec = mi->mrec; err = ntfs_write_bh(sbi, &rec->rhdr, &mi->nb, wait); if (err) return err; if (mi->rno < sbi->mft.recs_mirr) sbi->flags |= NTFS_FLAGS_MFTMIRR; mi->dirty = false; return 0; } int mi_format_new(struct mft_inode *mi, struct ntfs_sb_info *sbi, CLST rno, __le16 flags, bool is_mft) { int err; u16 seq = 1; struct MFT_REC *rec; u64 vbo = (u64)rno << sbi->record_bits; err = mi_init(mi, sbi, rno); if (err) return err; rec = mi->mrec; if (rno == MFT_REC_MFT) { ; } else if (rno < MFT_REC_FREE) { seq = rno; } else if (rno >= sbi->mft.used) { ; } else if (mi_read(mi, is_mft)) { ; } else if (rec->rhdr.sign == NTFS_FILE_SIGNATURE) { /* Record is reused. Update its sequence number. */ seq = le16_to_cpu(rec->seq) + 1; if (!seq) seq = 1; } memcpy(rec, sbi->new_rec, sbi->record_size); rec->seq = cpu_to_le16(seq); rec->flags = RECORD_FLAG_IN_USE | flags; if (MFTRECORD_FIXUP_OFFSET == MFTRECORD_FIXUP_OFFSET_3) rec->mft_record = cpu_to_le32(rno); mi->dirty = true; if (!mi->nb.nbufs) { struct ntfs_inode *ni = sbi->mft.ni; bool lock = false; if (is_mounted(sbi) && !is_mft) { down_read(&ni->file.run_lock); lock = true; } err = ntfs_get_bh(sbi, &ni->file.run, vbo, sbi->record_size, &mi->nb); if (lock) up_read(&ni->file.run_lock); } return err; } /* * mi_insert_attr - Reserve space for new attribute. * * Return: Not full constructed attribute or NULL if not possible to create. */ struct ATTRIB *mi_insert_attr(struct mft_inode *mi, enum ATTR_TYPE type, const __le16 *name, u8 name_len, u32 asize, u16 name_off) { size_t tail; struct ATTRIB *attr; __le16 id; struct MFT_REC *rec = mi->mrec; struct ntfs_sb_info *sbi = mi->sbi; u32 used = le32_to_cpu(rec->used); const u16 *upcase = sbi->upcase; /* Can we insert mi attribute? */ if (used + asize > sbi->record_size) return NULL; /* * Scan through the list of attributes to find the point * at which we should insert it. */ attr = NULL; while ((attr = mi_enum_attr(mi, attr))) { int diff = compare_attr(attr, type, name, name_len, upcase); if (diff < 0) continue; if (!diff && !is_attr_indexed(attr)) return NULL; break; } if (!attr) { /* Append. */ tail = 8; attr = Add2Ptr(rec, used - 8); } else { /* Insert before 'attr'. */ tail = used - PtrOffset(rec, attr); } id = mi_new_attt_id(mi); memmove(Add2Ptr(attr, asize), attr, tail); memset(attr, 0, asize); attr->type = type; attr->size = cpu_to_le32(asize); attr->name_len = name_len; attr->name_off = cpu_to_le16(name_off); attr->id = id; memmove(Add2Ptr(attr, name_off), name, name_len * sizeof(short)); rec->used = cpu_to_le32(used + asize); mi->dirty = true; return attr; } /* * mi_remove_attr - Remove the attribute from record. * * NOTE: The source attr will point to next attribute. */ bool mi_remove_attr(struct ntfs_inode *ni, struct mft_inode *mi, struct ATTRIB *attr) { struct MFT_REC *rec = mi->mrec; u32 aoff = PtrOffset(rec, attr); u32 used = le32_to_cpu(rec->used); u32 asize = le32_to_cpu(attr->size); if (aoff + asize > used) return false; if (ni && is_attr_indexed(attr)) { u16 links = le16_to_cpu(ni->mi.mrec->hard_links); struct ATTR_FILE_NAME *fname = attr->type != ATTR_NAME ? NULL : resident_data_ex(attr, SIZEOF_ATTRIBUTE_FILENAME); if (fname && fname->type == FILE_NAME_DOS) { /* Do not decrease links count deleting DOS name. */ } else if (!links) { /* minor error. Not critical. */ } else { ni->mi.mrec->hard_links = cpu_to_le16(links - 1); ni->mi.dirty = true; } } used -= asize; memmove(attr, Add2Ptr(attr, asize), used - aoff); rec->used = cpu_to_le32(used); mi->dirty = true; return true; } /* bytes = "new attribute size" - "old attribute size" */ bool mi_resize_attr(struct mft_inode *mi, struct ATTRIB *attr, int bytes) { struct MFT_REC *rec = mi->mrec; u32 aoff = PtrOffset(rec, attr); u32 total, used = le32_to_cpu(rec->used); u32 nsize, asize = le32_to_cpu(attr->size); u32 rsize = le32_to_cpu(attr->res.data_size); int tail = (int)(used - aoff - asize); int dsize; char *next; if (tail < 0 || aoff >= used) return false; if (!bytes) return true; total = le32_to_cpu(rec->total); next = Add2Ptr(attr, asize); if (bytes > 0) { dsize = ALIGN(bytes, 8); if (used + dsize > total) return false; nsize = asize + dsize; /* Move tail */ memmove(next + dsize, next, tail); memset(next, 0, dsize); used += dsize; rsize += dsize; } else { dsize = ALIGN(-bytes, 8); if (dsize > asize) return false; nsize = asize - dsize; memmove(next - dsize, next, tail); used -= dsize; rsize -= dsize; } rec->used = cpu_to_le32(used); attr->size = cpu_to_le32(nsize); if (!attr->non_res) attr->res.data_size = cpu_to_le32(rsize); mi->dirty = true; return true; } /* * Pack runs in MFT record. * If failed record is not changed. */ int mi_pack_runs(struct mft_inode *mi, struct ATTRIB *attr, struct runs_tree *run, CLST len) { int err = 0; struct ntfs_sb_info *sbi = mi->sbi; u32 new_run_size; CLST plen; struct MFT_REC *rec = mi->mrec; CLST svcn = le64_to_cpu(attr->nres.svcn); u32 used = le32_to_cpu(rec->used); u32 aoff = PtrOffset(rec, attr); u32 asize = le32_to_cpu(attr->size); char *next = Add2Ptr(attr, asize); u16 run_off = le16_to_cpu(attr->nres.run_off); u32 run_size = asize - run_off; u32 tail = used - aoff - asize; u32 dsize = sbi->record_size - used; /* Make a maximum gap in current record. */ memmove(next + dsize, next, tail); /* Pack as much as possible. */ err = run_pack(run, svcn, len, Add2Ptr(attr, run_off), run_size + dsize, &plen); if (err < 0) { memmove(next, next + dsize, tail); return err; } new_run_size = ALIGN(err, 8); memmove(next + new_run_size - run_size, next + dsize, tail); attr->size = cpu_to_le32(asize + new_run_size - run_size); attr->nres.evcn = cpu_to_le64(svcn + plen - 1); rec->used = cpu_to_le32(used + new_run_size - run_size); mi->dirty = true; return 0; }