Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull UDF and quota updates from Jan Kara:
 "This contains a rewrite of UDF handling of filename encoding to fix
  remaining overflow issues from Andrew Gabbasov and quota changes to
  support new Q_[X]GETNEXTQUOTA quotactl for VFS quota formats"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  quota: Fix possible GPF due to uninitialised pointers
  ext4: Make Q_GETNEXTQUOTA work for quota in hidden inodes
  quota: Forbid Q_GETQUOTA and Q_GETNEXTQUOTA for frozen filesystem
  quota: Fix possible races during quota loading
  ocfs2: Implement get_next_id()
  quota_v2: Implement get_next_id() for V2 quota format
  quota: Add support for ->get_nextdqblk() for VFS quota
  udf: Merge linux specific translation into CS0 conversion function
  udf: Remove struct ustr as non-needed intermediate storage
  udf: Use separate buffer for copying split names
  udf: Adjust UDF_NAME_LEN to better reflect actual restrictions
  udf: Join functions for UTF8 and NLS conversions
  udf: Parameterize output length in udf_put_filename
  quota: Allow Q_GETQUOTA for frozen filesystem
  quota: Fixup comments about return value of Q_[X]GETNEXTQUOTA

4 files changed, 130 insertions, 7 deletions

diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index 04ca0cc6d065..ba827daea5a0 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -411,6 +411,8 @@ int dquot_acquire(struct dquot *dquot)
 		ret = dqopt->ops[dquot->dq_id.type]->read_dqblk(dquot);
 	if (ret < 0)
 		goto out_iolock;
+	/* Make sure flags update is visible after dquot has been filled */
+	smp_mb__before_atomic();
 	set_bit(DQ_READ_B, &dquot->dq_flags);
 	/* Instantiate dquot if needed */
 	if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) {
@@ -427,6 +429,11 @@ int dquot_acquire(struct dquot *dquot)
 			goto out_iolock;
 		}
 	}
+	/*
+	 * Make sure flags update is visible after on-disk struct has been
+	 * allocated. Paired with smp_rmb() in dqget().
+	 */
+	smp_mb__before_atomic();
 	set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
 out_iolock:
 	mutex_unlock(&dqopt->dqio_mutex);
@@ -887,6 +894,11 @@ we_slept:
 			goto out;
 		}
 	}
+	/*
+	 * Make sure following reads see filled structure - paired with
+	 * smp_mb__before_atomic() in dquot_acquire().
+	 */
+	smp_rmb();
 #ifdef CONFIG_QUOTA_DEBUG
 	BUG_ON(!dquot->dq_sb);	/* Has somebody invalidated entry under us? */
 #endif
@@ -1398,7 +1410,7 @@ static int dquot_active(const struct inode *inode)
 static int __dquot_initialize(struct inode *inode, int type)
 {
 	int cnt, init_needed = 0;
-	struct dquot **dquots, *got[MAXQUOTAS];
+	struct dquot **dquots, *got[MAXQUOTAS] = {};
 	struct super_block *sb = inode->i_sb;
 	qsize_t rsv;
 	int ret = 0;
@@ -1415,7 +1427,6 @@ static int __dquot_initialize(struct inode *inode, int type)
 		int rc;
 		struct dquot *dquot;
 
-		got[cnt] = NULL;
 		if (type != -1 && cnt != type)
 			continue;
 		/*
@@ -2031,6 +2042,21 @@ int dquot_commit_info(struct super_block *sb, int type)
 }
 EXPORT_SYMBOL(dquot_commit_info);
 
+int dquot_get_next_id(struct super_block *sb, struct kqid *qid)
+{
+	struct quota_info *dqopt = sb_dqopt(sb);
+	int err;
+
+	if (!dqopt->ops[qid->type]->get_next_id)
+		return -ENOSYS;
+	mutex_lock(&dqopt->dqio_mutex);
+	err = dqopt->ops[qid->type]->get_next_id(sb, qid);
+	mutex_unlock(&dqopt->dqio_mutex);
+
+	return err;
+}
+EXPORT_SYMBOL(dquot_get_next_id);
+
 /*
  * Definitions of diskquota operations.
  */
@@ -2042,6 +2068,7 @@ const struct dquot_operations dquot_operations = {
 	.write_info	= dquot_commit_info,
 	.alloc_dquot	= dquot_alloc,
 	.destroy_dquot	= dquot_destroy,
+	.get_next_id	= dquot_get_next_id,
 };
 EXPORT_SYMBOL(dquot_operations);
 
@@ -2563,6 +2590,27 @@ int dquot_get_dqblk(struct super_block *sb, struct kqid qid,
 }
 EXPORT_SYMBOL(dquot_get_dqblk);
 
+int dquot_get_next_dqblk(struct super_block *sb, struct kqid *qid,
+			 struct qc_dqblk *di)
+{
+	struct dquot *dquot;
+	int err;
+
+	if (!sb->dq_op->get_next_id)
+		return -ENOSYS;
+	err = sb->dq_op->get_next_id(sb, qid);
+	if (err < 0)
+		return err;
+	dquot = dqget(sb, *qid);
+	if (IS_ERR(dquot))
+		return PTR_ERR(dquot);
+	do_get_dqblk(dquot, di);
+	dqput(dquot);
+
+	return 0;
+}
+EXPORT_SYMBOL(dquot_get_next_dqblk);
+
 #define VFS_QC_MASK \
 	(QC_SPACE | QC_SPC_SOFT | QC_SPC_HARD | \
 	 QC_INO_COUNT | QC_INO_SOFT | QC_INO_HARD | \
@@ -2763,6 +2811,7 @@ const struct quotactl_ops dquot_quotactl_ops = {
 	.get_state	= dquot_get_state,
 	.set_info	= dquot_set_dqinfo,
 	.get_dqblk	= dquot_get_dqblk,
+	.get_nextdqblk	= dquot_get_next_dqblk,
 	.set_dqblk	= dquot_set_dqblk
 };
 EXPORT_SYMBOL(dquot_quotactl_ops);
@@ -2774,6 +2823,7 @@ const struct quotactl_ops dquot_quotactl_sysfile_ops = {
 	.get_state	= dquot_get_state,
 	.set_info	= dquot_set_dqinfo,
 	.get_dqblk	= dquot_get_dqblk,
+	.get_nextdqblk	= dquot_get_next_dqblk,
 	.set_dqblk	= dquot_set_dqblk
 };
 EXPORT_SYMBOL(dquot_quotactl_sysfile_ops);
diff --git a/fs/quota/quota.c b/fs/quota/quota.c
index 0ebc90496525..0f10ee9892ce 100644
--- a/fs/quota/quota.c
+++ b/fs/quota/quota.c
@@ -224,7 +224,7 @@ static int quota_getquota(struct super_block *sb, int type, qid_t id,
 
 /*
  * Return quota for next active quota >= this id, if any exists,
- * otherwise return -ESRCH via ->get_nextdqblk
+ * otherwise return -ENOENT via ->get_nextdqblk
  */
 static int quota_getnextquota(struct super_block *sb, int type, qid_t id,
 			  void __user *addr)
@@ -655,7 +655,7 @@ static int quota_getxquota(struct super_block *sb, int type, qid_t id,
 
 /*
  * Return quota for next active quota >= this id, if any exists,
- * otherwise return -ESRCH via ->get_nextdqblk.
+ * otherwise return -ENOENT via ->get_nextdqblk.
  */
 static int quota_getnextxquota(struct super_block *sb, int type, qid_t id,
 			    void __user *addr)
@@ -765,10 +765,14 @@ static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
 /* Return 1 if 'cmd' will block on frozen filesystem */
 static int quotactl_cmd_write(int cmd)
 {
+	/*
+	 * We cannot allow Q_GETQUOTA and Q_GETNEXTQUOTA without write access
+	 * as dquot_acquire() may allocate space for new structure and OCFS2
+	 * needs to increment on-disk use count.
+	 */
 	switch (cmd) {
 	case Q_GETFMT:
 	case Q_GETINFO:
-	case Q_GETNEXTQUOTA:
 	case Q_SYNC:
 	case Q_XGETQSTAT:
 	case Q_XGETQSTATV:
diff --git a/fs/quota/quota_tree.c b/fs/quota/quota_tree.c
index 58efb83dec1c..0738972e8d3f 100644
--- a/fs/quota/quota_tree.c
+++ b/fs/quota/quota_tree.c
@@ -22,10 +22,9 @@ MODULE_LICENSE("GPL");
 
 #define __QUOTA_QT_PARANOIA
 
-static int get_index(struct qtree_mem_dqinfo *info, struct kqid qid, int depth)
+static int __get_index(struct qtree_mem_dqinfo *info, qid_t id, int depth)
 {
 	unsigned int epb = info->dqi_usable_bs >> 2;
-	qid_t id = from_kqid(&init_user_ns, qid);
 
 	depth = info->dqi_qtree_depth - depth - 1;
 	while (depth--)
@@ -33,6 +32,13 @@ static int get_index(struct qtree_mem_dqinfo *info, struct kqid qid, int depth)
 	return id % epb;
 }
 
+static int get_index(struct qtree_mem_dqinfo *info, struct kqid qid, int depth)
+{
+	qid_t id = from_kqid(&init_user_ns, qid);
+
+	return __get_index(info, id, depth);
+}
+
 /* Number of entries in one blocks */
 static int qtree_dqstr_in_blk(struct qtree_mem_dqinfo *info)
 {
@@ -668,3 +674,60 @@ int qtree_release_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot)
 	return 0;
 }
 EXPORT_SYMBOL(qtree_release_dquot);
+
+static int find_next_id(struct qtree_mem_dqinfo *info, qid_t *id,
+			unsigned int blk, int depth)
+{
+	char *buf = getdqbuf(info->dqi_usable_bs);
+	__le32 *ref = (__le32 *)buf;
+	ssize_t ret;
+	unsigned int epb = info->dqi_usable_bs >> 2;
+	unsigned int level_inc = 1;
+	int i;
+
+	if (!buf)
+		return -ENOMEM;
+
+	for (i = depth; i < info->dqi_qtree_depth - 1; i++)
+		level_inc *= epb;
+
+	ret = read_blk(info, blk, buf);
+	if (ret < 0) {
+		quota_error(info->dqi_sb,
+			    "Can't read quota tree block %u", blk);
+		goto out_buf;
+	}
+	for (i = __get_index(info, *id, depth); i < epb; i++) {
+		if (ref[i] == cpu_to_le32(0)) {
+			*id += level_inc;
+			continue;
+		}
+		if (depth == info->dqi_qtree_depth - 1) {
+			ret = 0;
+			goto out_buf;
+		}
+		ret = find_next_id(info, id, le32_to_cpu(ref[i]), depth + 1);
+		if (ret != -ENOENT)
+			break;
+	}
+	if (i == epb) {
+		ret = -ENOENT;
+		goto out_buf;
+	}
+out_buf:
+	kfree(buf);
+	return ret;
+}
+
+int qtree_get_next_id(struct qtree_mem_dqinfo *info, struct kqid *qid)
+{
+	qid_t id = from_kqid(&init_user_ns, *qid);
+	int ret;
+
+	ret = find_next_id(info, &id, QT_TREEOFF, 0);
+	if (ret < 0)
+		return ret;
+	*qid = make_kqid(&init_user_ns, qid->type, id);
+	return 0;
+}
+EXPORT_SYMBOL(qtree_get_next_id);
diff --git a/fs/quota/quota_v2.c b/fs/quota/quota_v2.c
index ed85d4f35c04..ca71bf881ad1 100644
--- a/fs/quota/quota_v2.c
+++ b/fs/quota/quota_v2.c
@@ -304,6 +304,11 @@ static int v2_free_file_info(struct super_block *sb, int type)
 	return 0;
 }
 
+static int v2_get_next_id(struct super_block *sb, struct kqid *qid)
+{
+	return qtree_get_next_id(sb_dqinfo(sb, qid->type)->dqi_priv, qid);
+}
+
 static const struct quota_format_ops v2_format_ops = {
 	.check_quota_file	= v2_check_quota_file,
 	.read_file_info		= v2_read_file_info,
@@ -312,6 +317,7 @@ static const struct quota_format_ops v2_format_ops = {
 	.read_dqblk		= v2_read_dquot,
 	.commit_dqblk		= v2_write_dquot,
 	.release_dqblk		= v2_release_dquot,
+	.get_next_id		= v2_get_next_id,
 };
 
 static struct quota_format_type v2r0_quota_format = {