From bb9397a356c6cc9a6e1d45633476fe83cf15a95f Mon Sep 17 00:00:00 2001 From: Tetsuhiro Kohada Date: Wed, 19 Feb 2020 14:57:27 +0900 Subject: [PATCH] staging: exfat: remove symlink feature. Remove symlink feature completely. Becouse -Uses reserved areas(defined in the Microsoft exfat specification), causing future incompatibilities. -Not described in Microsoft exfat specifications or SD standards. -For REMOVABLE media, causes incompatibility with other implementations. -Not supported by other major exfat drivers. -Not implemented symlink feature in linux FAT/VFAT. Remove this feature completely because of serious media compatibility issues. (Can't enable even with CONFIG) If you have any questions about this patch, please let me know. Reviewed-by: Takahiro Mori Acked-by: Valdis Kletnieks Signed-off-by: Tetsuhiro Kohada Link: https://lore.kernel.org/r/20200219055727.12867-1-Kohada.Tetsuhiro@dc.MitsubishiElectric.co.jp Signed-off-by: Greg Kroah-Hartman --- drivers/staging/exfat/exfat_super.c | 450 ------------------------------------ 1 file changed, 450 deletions(-) diff --git a/drivers/staging/exfat/exfat_super.c b/drivers/staging/exfat/exfat_super.c index b398114..c7bc07e 100644 --- a/drivers/staging/exfat/exfat_super.c +++ b/drivers/staging/exfat/exfat_super.c @@ -660,375 +660,6 @@ out: return ret; } -static int ffsReadFile(struct inode *inode, struct file_id_t *fid, void *buffer, - u64 count, u64 *rcount) -{ - s32 offset, sec_offset, clu_offset; - u32 clu; - int ret = 0; - sector_t LogSector; - u64 oneblkread, read_bytes; - struct buffer_head *tmp_bh = NULL; - struct super_block *sb = inode->i_sb; - struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info); - struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info); - - /* check the validity of the given file id */ - if (!fid) - return -EINVAL; - - /* check the validity of pointer parameters */ - if (!buffer) - return -EINVAL; - - /* acquire the lock for file system critical section */ - mutex_lock(&p_fs->v_mutex); - - /* check if the given file ID is opened */ - if (fid->type != TYPE_FILE) { - ret = -EPERM; - goto out; - } - - if (fid->rwoffset > fid->size) - fid->rwoffset = fid->size; - - if (count > (fid->size - fid->rwoffset)) - count = fid->size - fid->rwoffset; - - if (count == 0) { - if (rcount) - *rcount = 0; - ret = 0; - goto out; - } - - read_bytes = 0; - - while (count > 0) { - clu_offset = (s32)(fid->rwoffset >> p_fs->cluster_size_bits); - clu = fid->start_clu; - - if (fid->flags == 0x03) { - clu += clu_offset; - } else { - /* hint information */ - if ((clu_offset > 0) && (fid->hint_last_off > 0) && - (clu_offset >= fid->hint_last_off)) { - clu_offset -= fid->hint_last_off; - clu = fid->hint_last_clu; - } - - while (clu_offset > 0) { - /* clu = exfat_fat_read(sb, clu); */ - if (exfat_fat_read(sb, clu, &clu) == -1) { - ret = -EIO; - goto out; - } - - clu_offset--; - } - } - - /* hint information */ - fid->hint_last_off = (s32)(fid->rwoffset >> - p_fs->cluster_size_bits); - fid->hint_last_clu = clu; - - /* byte offset in cluster */ - offset = (s32)(fid->rwoffset & (p_fs->cluster_size - 1)); - - /* sector offset in cluster */ - sec_offset = offset >> p_bd->sector_size_bits; - - /* byte offset in sector */ - offset &= p_bd->sector_size_mask; - - LogSector = START_SECTOR(clu) + sec_offset; - - oneblkread = (u64)(p_bd->sector_size - offset); - if (oneblkread > count) - oneblkread = count; - - if ((offset == 0) && (oneblkread == p_bd->sector_size)) { - if (sector_read(sb, LogSector, &tmp_bh, 1) != - 0) - goto err_out; - memcpy((char *)buffer + read_bytes, - (char *)tmp_bh->b_data, (s32)oneblkread); - } else { - if (sector_read(sb, LogSector, &tmp_bh, 1) != - 0) - goto err_out; - memcpy((char *)buffer + read_bytes, - (char *)tmp_bh->b_data + offset, - (s32)oneblkread); - } - count -= oneblkread; - read_bytes += oneblkread; - fid->rwoffset += oneblkread; - } - brelse(tmp_bh); - -/* How did this ever work and not leak a brlse()?? */ -err_out: - /* set the size of read bytes */ - if (rcount) - *rcount = read_bytes; - - if (p_fs->dev_ejected) - ret = -EIO; - -out: - /* release the lock for file system critical section */ - mutex_unlock(&p_fs->v_mutex); - - return ret; -} - -static int ffsWriteFile(struct inode *inode, struct file_id_t *fid, - void *buffer, u64 count, u64 *wcount) -{ - bool modified = false; - s32 offset, sec_offset, clu_offset; - s32 num_clusters, num_alloc, num_alloced = (s32)~0; - int ret = 0; - u32 clu, last_clu; - sector_t LogSector; - u64 oneblkwrite, write_bytes; - struct chain_t new_clu; - struct timestamp_t tm; - struct dentry_t *ep, *ep2; - struct entry_set_cache_t *es = NULL; - struct buffer_head *tmp_bh = NULL; - struct super_block *sb = inode->i_sb; - struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info); - struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info); - - /* check the validity of the given file id */ - if (!fid) - return -EINVAL; - - /* check the validity of pointer parameters */ - if (!buffer) - return -EINVAL; - - /* acquire the lock for file system critical section */ - mutex_lock(&p_fs->v_mutex); - - /* check if the given file ID is opened */ - if (fid->type != TYPE_FILE) { - ret = -EPERM; - goto out; - } - - if (fid->rwoffset > fid->size) - fid->rwoffset = fid->size; - - if (count == 0) { - if (wcount) - *wcount = 0; - ret = 0; - goto out; - } - - fs_set_vol_flags(sb, VOL_DIRTY); - - if (fid->size == 0) - num_clusters = 0; - else - num_clusters = (s32)((fid->size - 1) >> - p_fs->cluster_size_bits) + 1; - - write_bytes = 0; - - while (count > 0) { - clu_offset = (s32)(fid->rwoffset >> p_fs->cluster_size_bits); - clu = fid->start_clu; - last_clu = fid->start_clu; - - if (fid->flags == 0x03) { - if ((clu_offset > 0) && (clu != CLUSTER_32(~0))) { - last_clu += clu_offset - 1; - - if (clu_offset == num_clusters) - clu = CLUSTER_32(~0); - else - clu += clu_offset; - } - } else { - /* hint information */ - if ((clu_offset > 0) && (fid->hint_last_off > 0) && - (clu_offset >= fid->hint_last_off)) { - clu_offset -= fid->hint_last_off; - clu = fid->hint_last_clu; - } - - while ((clu_offset > 0) && (clu != CLUSTER_32(~0))) { - last_clu = clu; - /* clu = exfat_fat_read(sb, clu); */ - if (exfat_fat_read(sb, clu, &clu) == -1) { - ret = -EIO; - goto out; - } - clu_offset--; - } - } - - if (clu == CLUSTER_32(~0)) { - num_alloc = (s32)((count - 1) >> - p_fs->cluster_size_bits) + 1; - new_clu.dir = (last_clu == CLUSTER_32(~0)) ? - CLUSTER_32(~0) : last_clu + 1; - new_clu.size = 0; - new_clu.flags = fid->flags; - - /* (1) allocate a chain of clusters */ - num_alloced = exfat_alloc_cluster(sb, - num_alloc, - &new_clu); - if (num_alloced == 0) - break; - if (num_alloced < 0) { - ret = num_alloced; - goto out; - } - - /* (2) append to the FAT chain */ - if (last_clu == CLUSTER_32(~0)) { - if (new_clu.flags == 0x01) - fid->flags = 0x01; - fid->start_clu = new_clu.dir; - modified = true; - } else { - if (new_clu.flags != fid->flags) { - exfat_chain_cont_cluster(sb, - fid->start_clu, - num_clusters); - fid->flags = 0x01; - modified = true; - } - if (new_clu.flags == 0x01) - exfat_fat_write(sb, last_clu, new_clu.dir); - } - - num_clusters += num_alloced; - clu = new_clu.dir; - } - - /* hint information */ - fid->hint_last_off = (s32)(fid->rwoffset >> - p_fs->cluster_size_bits); - fid->hint_last_clu = clu; - - /* byte offset in cluster */ - offset = (s32)(fid->rwoffset & (p_fs->cluster_size - 1)); - - /* sector offset in cluster */ - sec_offset = offset >> p_bd->sector_size_bits; - - /* byte offset in sector */ - offset &= p_bd->sector_size_mask; - - LogSector = START_SECTOR(clu) + sec_offset; - - oneblkwrite = (u64)(p_bd->sector_size - offset); - if (oneblkwrite > count) - oneblkwrite = count; - - if ((offset == 0) && (oneblkwrite == p_bd->sector_size)) { - if (sector_read(sb, LogSector, &tmp_bh, 0) != - 0) - goto err_out; - memcpy((char *)tmp_bh->b_data, - (char *)buffer + write_bytes, (s32)oneblkwrite); - if (sector_write(sb, LogSector, tmp_bh, 0) != - 0) { - brelse(tmp_bh); - goto err_out; - } - } else { - if ((offset > 0) || - ((fid->rwoffset + oneblkwrite) < fid->size)) { - if (sector_read(sb, LogSector, &tmp_bh, 1) != - 0) - goto err_out; - } else { - if (sector_read(sb, LogSector, &tmp_bh, 0) != - 0) - goto err_out; - } - - memcpy((char *)tmp_bh->b_data + offset, - (char *)buffer + write_bytes, (s32)oneblkwrite); - if (sector_write(sb, LogSector, tmp_bh, 0) != - 0) { - brelse(tmp_bh); - goto err_out; - } - } - - count -= oneblkwrite; - write_bytes += oneblkwrite; - fid->rwoffset += oneblkwrite; - - fid->attr |= ATTR_ARCHIVE; - - if (fid->size < fid->rwoffset) { - fid->size = fid->rwoffset; - modified = true; - } - } - - brelse(tmp_bh); - - /* (3) update the direcoty entry */ - es = get_entry_set_in_dir(sb, &fid->dir, fid->entry, - ES_ALL_ENTRIES, &ep); - if (!es) - goto err_out; - ep2 = ep + 1; - - exfat_set_entry_time(ep, tm_current(&tm), TM_MODIFY); - exfat_set_entry_attr(ep, fid->attr); - - if (modified) { - if (exfat_get_entry_flag(ep2) != fid->flags) - exfat_set_entry_flag(ep2, fid->flags); - - if (exfat_get_entry_size(ep2) != fid->size) - exfat_set_entry_size(ep2, fid->size); - - if (exfat_get_entry_clu0(ep2) != fid->start_clu) - exfat_set_entry_clu0(ep2, fid->start_clu); - } - - update_dir_checksum_with_entry_set(sb, es); - release_entry_set(es); - -#ifndef CONFIG_STAGING_EXFAT_DELAYED_SYNC - fs_sync(sb, true); - fs_set_vol_flags(sb, VOL_CLEAN); -#endif - -err_out: - /* set the size of written bytes */ - if (wcount) - *wcount = write_bytes; - - if (num_alloced == 0) - ret = -ENOSPC; - - else if (p_fs->dev_ejected) - ret = -EIO; - -out: - /* release the lock for file system critical section */ - mutex_unlock(&p_fs->v_mutex); - - return ret; -} - static int ffsTruncateFile(struct inode *inode, u64 old_size, u64 new_size) { s32 num_clusters; @@ -2273,7 +1904,6 @@ static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry, int err; struct file_id_t fid; loff_t i_pos; - u64 ret; mode_t i_mode; __lock_super(sb); @@ -2295,18 +1925,6 @@ static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry, } i_mode = inode->i_mode; - if (S_ISLNK(i_mode) && !EXFAT_I(inode)->target) { - EXFAT_I(inode)->target = kmalloc(i_size_read(inode) + 1, - GFP_KERNEL); - if (!EXFAT_I(inode)->target) { - err = -ENOMEM; - goto error; - } - ffsReadFile(dir, &fid, EXFAT_I(inode)->target, - i_size_read(inode), &ret); - *(EXFAT_I(inode)->target + i_size_read(inode)) = '\0'; - } - alias = d_find_alias(inode); if (alias && !exfat_d_anon_disconn(alias)) { BUG_ON(d_unhashed(alias)); @@ -2398,73 +2016,6 @@ out: return err; } -static int exfat_symlink(struct inode *dir, struct dentry *dentry, - const char *target) -{ - struct super_block *sb = dir->i_sb; - struct timespec64 curtime; - struct inode *inode; - struct file_id_t fid; - loff_t i_pos; - int err; - u64 len = (u64)strlen(target); - u64 ret; - - __lock_super(sb); - - pr_debug("%s entered\n", __func__); - - err = ffsCreateFile(dir, (u8 *)dentry->d_name.name, FM_SYMLINK, &fid); - if (err) - goto out; - - - err = ffsWriteFile(dir, &fid, (char *)target, len, &ret); - - if (err) { - ffsRemoveFile(dir, &fid); - goto out; - } - - INC_IVERSION(dir); - curtime = current_time(dir); - dir->i_ctime = curtime; - dir->i_mtime = curtime; - dir->i_atime = curtime; - if (IS_DIRSYNC(dir)) - (void)exfat_sync_inode(dir); - else - mark_inode_dirty(dir); - - i_pos = ((loff_t)fid.dir.dir << 32) | (fid.entry & 0xffffffff); - - inode = exfat_build_inode(sb, &fid, i_pos); - if (IS_ERR(inode)) { - err = PTR_ERR(inode); - goto out; - } - INC_IVERSION(inode); - curtime = current_time(inode); - inode->i_mtime = curtime; - inode->i_atime = curtime; - inode->i_ctime = curtime; - /* timestamp is already written, so mark_inode_dirty() is unneeded. */ - - EXFAT_I(inode)->target = kmemdup(target, len + 1, GFP_KERNEL); - if (!EXFAT_I(inode)->target) { - err = -ENOMEM; - goto out; - } - - dentry->d_time = GET_IVERSION(dentry->d_parent->d_inode); - d_instantiate(dentry, inode); - -out: - __unlock_super(sb); - pr_debug("%s exited\n", __func__); - return err; -} - static int exfat_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) { struct super_block *sb = dir->i_sb; @@ -2838,7 +2389,6 @@ static const struct inode_operations exfat_dir_inode_operations = { .create = exfat_create, .lookup = exfat_lookup, .unlink = exfat_unlink, - .symlink = exfat_symlink, .mkdir = exfat_mkdir, .rmdir = exfat_rmdir, .rename = exfat_rename, -- 2.7.4