// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. */ #include #include #include #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0) #include #endif #include #include #include "exfat_raw.h" #include "exfat_fs.h" static int exfat_cont_expand(struct inode *inode, loff_t size) { struct address_space *mapping = inode->i_mapping; loff_t start = i_size_read(inode), count = size - i_size_read(inode); int err, err2; err = generic_cont_expand_simple(inode, size); if (err) return err; #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0) inode->i_ctime = inode->i_mtime = current_time(inode); #else inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC; #endif mark_inode_dirty(inode); if (!IS_SYNC(inode)) return 0; err = filemap_fdatawrite_range(mapping, start, start + count - 1); err2 = sync_mapping_buffers(mapping); if (!err) err = err2; err2 = write_inode_now(inode, 1); if (!err) err = err2; if (err) return err; return filemap_fdatawait_range(mapping, start, start + count - 1); } static bool exfat_allow_set_time(struct exfat_sb_info *sbi, struct inode *inode) { mode_t allow_utime = sbi->options.allow_utime; if (!uid_eq(current_fsuid(), inode->i_uid)) { if (in_group_p(inode->i_gid)) allow_utime >>= 3; if (allow_utime & MAY_WRITE) return true; } /* use a default check */ return false; } static int exfat_sanitize_mode(const struct exfat_sb_info *sbi, struct inode *inode, umode_t *mode_ptr) { mode_t i_mode, mask, perm; i_mode = inode->i_mode; mask = (S_ISREG(i_mode) || S_ISLNK(i_mode)) ? sbi->options.fs_fmask : sbi->options.fs_dmask; perm = *mode_ptr & ~(S_IFMT | mask); /* Of the r and x bits, all (subject to umask) must be present.*/ if ((perm & 0555) != (i_mode & 0555)) return -EPERM; if (exfat_mode_can_hold_ro(inode)) { /* * Of the w bits, either all (subject to umask) or none must * be present. */ if ((perm & 0222) && ((perm & 0222) != (0222 & ~mask))) return -EPERM; } else { /* * If exfat_mode_can_hold_ro(inode) is false, can't change * w bits. */ if ((perm & 0222) != (0222 & ~mask)) return -EPERM; } *mode_ptr &= S_IFMT | perm; return 0; } /* resize the file length */ int __exfat_truncate(struct inode *inode, loff_t new_size) { unsigned int num_clusters_new, num_clusters_phys; unsigned int last_clu = EXFAT_FREE_CLUSTER; struct exfat_chain clu; struct super_block *sb = inode->i_sb; struct exfat_sb_info *sbi = EXFAT_SB(sb); struct exfat_inode_info *ei = EXFAT_I(inode); int evict = (ei->dir.dir == DIR_DELETED) ? 1 : 0; /* check if the given file ID is opened */ if (ei->type != TYPE_FILE && ei->type != TYPE_DIR) return -EPERM; exfat_set_volume_dirty(sb); num_clusters_new = EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi); num_clusters_phys = EXFAT_B_TO_CLU_ROUND_UP(ei->i_size_ondisk, sbi); exfat_chain_set(&clu, ei->start_clu, num_clusters_phys, ei->flags); if (new_size > 0) { /* * Truncate FAT chain num_clusters after the first cluster * num_clusters = min(new, phys); */ unsigned int num_clusters = min(num_clusters_new, num_clusters_phys); /* * Follow FAT chain * (defensive coding - works fine even with corrupted FAT table */ if (clu.flags == ALLOC_NO_FAT_CHAIN) { clu.dir += num_clusters; clu.size -= num_clusters; } else { while (num_clusters > 0) { last_clu = clu.dir; if (exfat_get_next_cluster(sb, &(clu.dir))) return -EIO; num_clusters--; clu.size--; } } } else { ei->flags = ALLOC_NO_FAT_CHAIN; ei->start_clu = EXFAT_EOF_CLUSTER; } i_size_write(inode, new_size); if (ei->type == TYPE_FILE) ei->attr |= ATTR_ARCHIVE; /* update the directory entry */ if (!evict) { #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 19, 0) struct timespec64 ts; #else struct timespec ts; #endif struct exfat_dentry *ep, *ep2; struct exfat_entry_set_cache *es; int err; es = exfat_get_dentry_set(sb, &(ei->dir), ei->entry, ES_ALL_ENTRIES); if (!es) return -EIO; ep = exfat_get_dentry_cached(es, 0); ep2 = exfat_get_dentry_cached(es, 1); #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0) ts = current_time(inode); #else ts = CURRENT_TIME_SEC; #endif exfat_set_entry_time(sbi, &ts, &ep->dentry.file.modify_tz, &ep->dentry.file.modify_time, &ep->dentry.file.modify_date, &ep->dentry.file.modify_time_cs); ep->dentry.file.attr = cpu_to_le16(ei->attr); /* File size should be zero if there is no cluster allocated */ if (ei->start_clu == EXFAT_EOF_CLUSTER) { ep2->dentry.stream.valid_size = 0; ep2->dentry.stream.size = 0; } else { ep2->dentry.stream.valid_size = cpu_to_le64(new_size); ep2->dentry.stream.size = ep2->dentry.stream.valid_size; } if (new_size == 0) { /* Any directory can not be truncated to zero */ WARN_ON(ei->type != TYPE_FILE); ep2->dentry.stream.flags = ALLOC_FAT_CHAIN; ep2->dentry.stream.start_clu = EXFAT_FREE_CLUSTER; } exfat_update_dir_chksum_with_entry_set(es); err = exfat_free_dentry_set(es, inode_needs_sync(inode)); if (err) return err; } /* cut off from the FAT chain */ if (ei->flags == ALLOC_FAT_CHAIN && last_clu != EXFAT_FREE_CLUSTER && last_clu != EXFAT_EOF_CLUSTER) { if (exfat_ent_set(sb, last_clu, EXFAT_EOF_CLUSTER)) return -EIO; } /* invalidate cache and free the clusters */ /* clear exfat cache */ exfat_cache_inval_inode(inode); /* hint information */ ei->hint_bmap.off = EXFAT_EOF_CLUSTER; ei->hint_bmap.clu = EXFAT_EOF_CLUSTER; /* hint_stat will be used if this is directory. */ ei->hint_stat.eidx = 0; ei->hint_stat.clu = ei->start_clu; ei->hint_femp.eidx = EXFAT_HINT_NONE; /* free the clusters */ if (exfat_free_cluster(inode, &clu)) return -EIO; return 0; } void exfat_truncate(struct inode *inode, loff_t size) { struct super_block *sb = inode->i_sb; struct exfat_sb_info *sbi = EXFAT_SB(sb); struct exfat_inode_info *ei = EXFAT_I(inode); #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 4, 72) unsigned int blocksize = i_blocksize(inode); #else unsigned int blocksize = 1 << inode->i_blkbits; #endif loff_t aligned_size; int err; mutex_lock(&sbi->s_lock); if (ei->start_clu == 0) { /* * Empty start_clu != ~0 (not allocated) */ exfat_fs_error(sb, "tried to truncate zeroed cluster."); goto write_size; } err = __exfat_truncate(inode, i_size_read(inode)); if (err) goto write_size; #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 10, 0) inode->i_ctime = inode->i_mtime = current_time(inode); #else inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC; #endif if (IS_DIRSYNC(inode)) exfat_sync_inode(inode); else mark_inode_dirty(inode); inode->i_blocks = ((i_size_read(inode) + (sbi->cluster_size - 1)) & ~((loff_t)sbi->cluster_size - 1)) >> inode->i_blkbits; write_size: aligned_size = i_size_read(inode); if (aligned_size & (blocksize - 1)) { aligned_size |= (blocksize - 1); aligned_size++; } if (ei->i_size_ondisk > i_size_read(inode)) ei->i_size_ondisk = aligned_size; if (ei->i_size_aligned > i_size_read(inode)) ei->i_size_aligned = aligned_size; mutex_unlock(&sbi->s_lock); } #if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 12, 0) int exfat_getattr(struct user_namespace *mnt_uerns, const struct path *path, struct kstat *stat, unsigned int request_mask, unsigned int query_flags) #else #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0) int exfat_getattr(const struct path *path, struct kstat *stat, unsigned int request_mask, unsigned int query_flags) #else int exfat_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) #endif #endif { #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0) struct inode *inode = d_backing_inode(path->dentry); struct exfat_inode_info *ei = EXFAT_I(inode); #else struct inode *inode = d_inode(dentry); #endif #if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 12, 0) generic_fillattr(&init_user_ns, inode, stat); #else generic_fillattr(inode, stat); #endif exfat_truncate_atime(&stat->atime); #if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0) stat->result_mask |= STATX_BTIME; stat->btime.tv_sec = ei->i_crtime.tv_sec; stat->btime.tv_nsec = ei->i_crtime.tv_nsec; #endif stat->blksize = EXFAT_SB(inode->i_sb)->cluster_size; return 0; } #if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 12, 0) int exfat_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, struct iattr *attr) #else int exfat_setattr(struct dentry *dentry, struct iattr *attr) #endif { struct exfat_sb_info *sbi = EXFAT_SB(dentry->d_sb); struct inode *inode = dentry->d_inode; unsigned int ia_valid; int error; if ((attr->ia_valid & ATTR_SIZE) && attr->ia_size > i_size_read(inode)) { error = exfat_cont_expand(inode, attr->ia_size); if (error || attr->ia_valid == ATTR_SIZE) return error; attr->ia_valid &= ~ATTR_SIZE; } /* Check for setting the inode time. */ ia_valid = attr->ia_valid; if ((ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) && exfat_allow_set_time(sbi, inode)) { attr->ia_valid &= ~(ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET); } #if ((LINUX_VERSION_CODE < KERNEL_VERSION(4, 2, 0)) && \ (LINUX_VERSION_CODE >= KERNEL_VERSION(4, 1, 37))) || \ (LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)) #if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 12, 0) error = setattr_prepare(&init_user_ns, dentry, attr); #else error = setattr_prepare(dentry, attr); #endif #else error = inode_change_ok(inode, attr); #endif attr->ia_valid = ia_valid; if (error) goto out; if (((attr->ia_valid & ATTR_UID) && !uid_eq(attr->ia_uid, sbi->options.fs_uid)) || ((attr->ia_valid & ATTR_GID) && !gid_eq(attr->ia_gid, sbi->options.fs_gid)) || ((attr->ia_valid & ATTR_MODE) && (attr->ia_mode & ~(S_IFREG | S_IFLNK | S_IFDIR | 0777)))) { error = -EPERM; goto out; } /* * We don't return -EPERM here. Yes, strange, but this is too * old behavior. */ if (attr->ia_valid & ATTR_MODE) { if (exfat_sanitize_mode(sbi, inode, &attr->ia_mode) < 0) attr->ia_valid &= ~ATTR_MODE; } if (attr->ia_valid & ATTR_SIZE) { error = exfat_block_truncate_page(inode, attr->ia_size); if (error) goto out; down_write(&EXFAT_I(inode)->truncate_lock); truncate_setsize(inode, attr->ia_size); exfat_truncate(inode, attr->ia_size); up_write(&EXFAT_I(inode)->truncate_lock); } #if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 12, 0) setattr_copy(&init_user_ns, inode, attr); #else setattr_copy(inode, attr); #endif exfat_truncate_atime(&inode->i_atime); mark_inode_dirty(inode); out: return error; } static int exfat_ioctl_fitrim(struct inode *inode, unsigned long arg) { struct request_queue *q = bdev_get_queue(inode->i_sb->s_bdev); struct fstrim_range range; int ret = 0; if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (!blk_queue_discard(q)) return -EOPNOTSUPP; if (copy_from_user(&range, (struct fstrim_range __user *)arg, sizeof(range))) return -EFAULT; range.minlen = max_t(unsigned int, range.minlen, q->limits.discard_granularity); ret = exfat_trim_fs(inode, &range); if (ret < 0) return ret; if (copy_to_user((struct fstrim_range __user *)arg, &range, sizeof(range))) return -EFAULT; return 0; } long exfat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { struct inode *inode = file_inode(filp); switch (cmd) { case FITRIM: return exfat_ioctl_fitrim(inode, arg); default: return -ENOTTY; } } #ifdef CONFIG_COMPAT long exfat_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { return exfat_ioctl(filp, cmd, (unsigned long)compat_ptr(arg)); } #endif int exfat_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync) { struct inode *inode = filp->f_mapping->host; int err; err = __generic_file_fsync(filp, start, end, datasync); if (err) return err; err = sync_blockdev(inode->i_sb->s_bdev); if (err) return err; #if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 12, 0) return blkdev_issue_flush(inode->i_sb->s_bdev); #else #if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 8, 0) return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); #else return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL); #endif #endif } const struct file_operations exfat_file_operations = { .llseek = generic_file_llseek, .read_iter = generic_file_read_iter, .write_iter = generic_file_write_iter, .unlocked_ioctl = exfat_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = exfat_compat_ioctl, #endif .mmap = generic_file_mmap, .fsync = exfat_file_fsync, .splice_read = generic_file_splice_read, .splice_write = iter_file_splice_write, }; const struct inode_operations exfat_file_inode_operations = { .setattr = exfat_setattr, .getattr = exfat_getattr, };