1 files changed, 182 insertions, 67 deletions

diff --git a/fs/quota/quota.c b/fs/quota/quota.c
index 95388f9b735..ff3f0b3cfdb 100644
--- a/fs/quota/quota.c
+++ b/fs/quota/quota.c
@@ -9,11 +9,10 @@
 #include <linux/namei.h>
 #include <linux/slab.h>
 #include <asm/current.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
 #include <linux/kernel.h>
 #include <linux/security.h>
 #include <linux/syscalls.h>
-#include <linux/buffer_head.h>
 #include <linux/capability.h>
 #include <linux/quotaops.h>
 #include <linux/types.h>
@@ -28,13 +27,14 @@ static int check_quotactl_permission(struct super_block *sb, int type, int cmd,
 	case Q_SYNC:
 	case Q_GETINFO:
 	case Q_XGETQSTAT:
+	case Q_XGETQSTATV:
 	case Q_XQUOTASYNC:
 		break;
 	/* allow to query information for dquots we "own" */
 	case Q_GETQUOTA:
 	case Q_XGETQUOTA:
-		if ((type == USRQUOTA && current_euid() == id) ||
-		    (type == GRPQUOTA && in_egroup_p(id)))
+		if ((type == USRQUOTA && uid_eq(current_euid(), make_kuid(current_user_ns(), id))) ||
+		    (type == GRPQUOTA && in_egroup_p(make_kgid(current_user_ns(), id))))
 			break;
 		/*FALLTHROUGH*/
 	default:
@@ -45,51 +45,34 @@ static int check_quotactl_permission(struct super_block *sb, int type, int cmd,
 	return security_quotactl(cmd, type, id, sb);
 }
 
+static void quota_sync_one(struct super_block *sb, void *arg)
+{
+	if (sb->s_qcop && sb->s_qcop->quota_sync)
+		sb->s_qcop->quota_sync(sb, *(int *)arg);
+}
+
 static int quota_sync_all(int type)
 {
-	struct super_block *sb;
 	int ret;
 
 	if (type >= MAXQUOTAS)
 		return -EINVAL;
 	ret = security_quotactl(Q_SYNC, type, 0, NULL);
-	if (ret)
-		return ret;
-
-	spin_lock(&sb_lock);
-restart:
-	list_for_each_entry(sb, &super_blocks, s_list) {
-		if (!sb->s_qcop || !sb->s_qcop->quota_sync)
-			continue;
-
-		sb->s_count++;
-		spin_unlock(&sb_lock);
-		down_read(&sb->s_umount);
-		if (sb->s_root)
-			sb->s_qcop->quota_sync(sb, type, 1);
-		up_read(&sb->s_umount);
-		spin_lock(&sb_lock);
-		if (__put_super_and_need_restart(sb))
-			goto restart;
-	}
-	spin_unlock(&sb_lock);
-
-	return 0;
+	if (!ret)
+		iterate_supers(quota_sync_one, &type);
+	return ret;
 }
 
 static int quota_quotaon(struct super_block *sb, int type, int cmd, qid_t id,
-		         void __user *addr)
+		         struct path *path)
 {
-	char *pathname;
-	int ret = -ENOSYS;
-
-	pathname = getname(addr);
-	if (IS_ERR(pathname))
-		return PTR_ERR(pathname);
-	if (sb->s_qcop->quota_on)
-		ret = sb->s_qcop->quota_on(sb, type, id, pathname, 0);
-	putname(pathname);
-	return ret;
+	if (!sb->s_qcop->quota_on && !sb->s_qcop->quota_on_meta)
+		return -ENOSYS;
+	if (sb->s_qcop->quota_on_meta)
+		return sb->s_qcop->quota_on_meta(sb, type, id);
+	if (IS_ERR(path))
+		return PTR_ERR(path);
+	return sb->s_qcop->quota_on(sb, type, id, path);
 }
 
 static int quota_getfmt(struct super_block *sb, int type, void __user *addr)
@@ -113,8 +96,6 @@ static int quota_getinfo(struct super_block *sb, int type, void __user *addr)
 	struct if_dqinfo info;
 	int ret;
 
-	if (!sb_has_quota_active(sb, type))
-		return -ESRCH;
 	if (!sb->s_qcop->get_info)
 		return -ENOSYS;
 	ret = sb->s_qcop->get_info(sb, type, &info);
@@ -129,43 +110,89 @@ static int quota_setinfo(struct super_block *sb, int type, void __user *addr)
 
 	if (copy_from_user(&info, addr, sizeof(info)))
 		return -EFAULT;
-	if (!sb_has_quota_active(sb, type))
-		return -ESRCH;
 	if (!sb->s_qcop->set_info)
 		return -ENOSYS;
 	return sb->s_qcop->set_info(sb, type, &info);
 }
 
+static void copy_to_if_dqblk(struct if_dqblk *dst, struct fs_disk_quota *src)
+{
+	memset(dst, 0, sizeof(*dst));
+	dst->dqb_bhardlimit = src->d_blk_hardlimit;
+	dst->dqb_bsoftlimit = src->d_blk_softlimit;
+	dst->dqb_curspace = src->d_bcount;
+	dst->dqb_ihardlimit = src->d_ino_hardlimit;
+	dst->dqb_isoftlimit = src->d_ino_softlimit;
+	dst->dqb_curinodes = src->d_icount;
+	dst->dqb_btime = src->d_btimer;
+	dst->dqb_itime = src->d_itimer;
+	dst->dqb_valid = QIF_ALL;
+}
+
 static int quota_getquota(struct super_block *sb, int type, qid_t id,
 			  void __user *addr)
 {
+	struct kqid qid;
+	struct fs_disk_quota fdq;
 	struct if_dqblk idq;
 	int ret;
 
-	if (!sb_has_quota_active(sb, type))
-		return -ESRCH;
 	if (!sb->s_qcop->get_dqblk)
 		return -ENOSYS;
-	ret = sb->s_qcop->get_dqblk(sb, type, id, &idq);
+	qid = make_kqid(current_user_ns(), type, id);
+	if (!qid_valid(qid))
+		return -EINVAL;
+	ret = sb->s_qcop->get_dqblk(sb, qid, &fdq);
 	if (ret)
 		return ret;
+	copy_to_if_dqblk(&idq, &fdq);
 	if (copy_to_user(addr, &idq, sizeof(idq)))
 		return -EFAULT;
 	return 0;
 }
 
+static void copy_from_if_dqblk(struct fs_disk_quota *dst, struct if_dqblk *src)
+{
+	dst->d_blk_hardlimit = src->dqb_bhardlimit;
+	dst->d_blk_softlimit  = src->dqb_bsoftlimit;
+	dst->d_bcount = src->dqb_curspace;
+	dst->d_ino_hardlimit = src->dqb_ihardlimit;
+	dst->d_ino_softlimit = src->dqb_isoftlimit;
+	dst->d_icount = src->dqb_curinodes;
+	dst->d_btimer = src->dqb_btime;
+	dst->d_itimer = src->dqb_itime;
+
+	dst->d_fieldmask = 0;
+	if (src->dqb_valid & QIF_BLIMITS)
+		dst->d_fieldmask |= FS_DQ_BSOFT | FS_DQ_BHARD;
+	if (src->dqb_valid & QIF_SPACE)
+		dst->d_fieldmask |= FS_DQ_BCOUNT;
+	if (src->dqb_valid & QIF_ILIMITS)
+		dst->d_fieldmask |= FS_DQ_ISOFT | FS_DQ_IHARD;
+	if (src->dqb_valid & QIF_INODES)
+		dst->d_fieldmask |= FS_DQ_ICOUNT;
+	if (src->dqb_valid & QIF_BTIME)
+		dst->d_fieldmask |= FS_DQ_BTIMER;
+	if (src->dqb_valid & QIF_ITIME)
+		dst->d_fieldmask |= FS_DQ_ITIMER;
+}
+
 static int quota_setquota(struct super_block *sb, int type, qid_t id,
 			  void __user *addr)
 {
+	struct fs_disk_quota fdq;
 	struct if_dqblk idq;
+	struct kqid qid;
 
 	if (copy_from_user(&idq, addr, sizeof(idq)))
 		return -EFAULT;
-	if (!sb_has_quota_active(sb, type))
-		return -ESRCH;
 	if (!sb->s_qcop->set_dqblk)
 		return -ENOSYS;
-	return sb->s_qcop->set_dqblk(sb, type, id, &idq);
+	qid = make_kqid(current_user_ns(), type, id);
+	if (!qid_valid(qid))
+		return -EINVAL;
+	copy_from_if_dqblk(&fdq, &idq);
+	return sb->s_qcop->set_dqblk(sb, qid, &fdq);
 }
 
 static int quota_setxstate(struct super_block *sb, int cmd, void __user *addr)
@@ -192,35 +219,79 @@ static int quota_getxstate(struct super_block *sb, void __user *addr)
 	return ret;
 }
 
+static int quota_getxstatev(struct super_block *sb, void __user *addr)
+{
+	struct fs_quota_statv fqs;
+	int ret;
+
+	if (!sb->s_qcop->get_xstatev)
+		return -ENOSYS;
+
+	memset(&fqs, 0, sizeof(fqs));
+	if (copy_from_user(&fqs, addr, 1)) /* Just read qs_version */
+		return -EFAULT;
+
+	/* If this kernel doesn't support user specified version, fail */
+	switch (fqs.qs_version) {
+	case FS_QSTATV_VERSION1:
+		break;
+	default:
+		return -EINVAL;
+	}
+	ret = sb->s_qcop->get_xstatev(sb, &fqs);
+	if (!ret && copy_to_user(addr, &fqs, sizeof(fqs)))
+		return -EFAULT;
+	return ret;
+}
+
 static int quota_setxquota(struct super_block *sb, int type, qid_t id,
 			   void __user *addr)
 {
 	struct fs_disk_quota fdq;
+	struct kqid qid;
 
 	if (copy_from_user(&fdq, addr, sizeof(fdq)))
 		return -EFAULT;
-	if (!sb->s_qcop->set_xquota)
+	if (!sb->s_qcop->set_dqblk)
 		return -ENOSYS;
-	return sb->s_qcop->set_xquota(sb, type, id, &fdq);
+	qid = make_kqid(current_user_ns(), type, id);
+	if (!qid_valid(qid))
+		return -EINVAL;
+	return sb->s_qcop->set_dqblk(sb, qid, &fdq);
 }
 
 static int quota_getxquota(struct super_block *sb, int type, qid_t id,
 			   void __user *addr)
 {
 	struct fs_disk_quota fdq;
+	struct kqid qid;
 	int ret;
 
-	if (!sb->s_qcop->get_xquota)
+	if (!sb->s_qcop->get_dqblk)
 		return -ENOSYS;
-	ret = sb->s_qcop->get_xquota(sb, type, id, &fdq);
+	qid = make_kqid(current_user_ns(), type, id);
+	if (!qid_valid(qid))
+		return -EINVAL;
+	ret = sb->s_qcop->get_dqblk(sb, qid, &fdq);
 	if (!ret && copy_to_user(addr, &fdq, sizeof(fdq)))
 		return -EFAULT;
 	return ret;
 }
 
+static int quota_rmxquota(struct super_block *sb, void __user *addr)
+{
+	__u32 flags;
+
+	if (copy_from_user(&flags, addr, sizeof(flags)))
+		return -EFAULT;
+	if (!sb->s_qcop->rm_xquota)
+		return -ENOSYS;
+	return sb->s_qcop->rm_xquota(sb, flags);
+}
+
 /* Copy parameters and call proper function */
 static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
-		       void __user *addr)
+		       void __user *addr, struct path *path)
 {
 	int ret;
 
@@ -235,11 +306,11 @@ static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
 
 	switch (cmd) {
 	case Q_QUOTAON:
-		return quota_quotaon(sb, type, cmd, id, addr);
+		return quota_quotaon(sb, type, cmd, id, path);
 	case Q_QUOTAOFF:
 		if (!sb->s_qcop->quota_off)
 			return -ENOSYS;
-		return sb->s_qcop->quota_off(sb, type, 0);
+		return sb->s_qcop->quota_off(sb, type);
 	case Q_GETFMT:
 		return quota_getfmt(sb, type, addr);
 	case Q_GETINFO:
@@ -253,46 +324,71 @@ static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
 	case Q_SYNC:
 		if (!sb->s_qcop->quota_sync)
 			return -ENOSYS;
-		return sb->s_qcop->quota_sync(sb, type, 1);
+		return sb->s_qcop->quota_sync(sb, type);
 	case Q_XQUOTAON:
 	case Q_XQUOTAOFF:
-	case Q_XQUOTARM:
 		return quota_setxstate(sb, cmd, addr);
+	case Q_XQUOTARM:
+		return quota_rmxquota(sb, addr);
 	case Q_XGETQSTAT:
 		return quota_getxstate(sb, addr);
+	case Q_XGETQSTATV:
+		return quota_getxstatev(sb, addr);
 	case Q_XSETQLIM:
 		return quota_setxquota(sb, type, id, addr);
 	case Q_XGETQUOTA:
 		return quota_getxquota(sb, type, id, addr);
 	case Q_XQUOTASYNC:
-		/* caller already holds s_umount */
 		if (sb->s_flags & MS_RDONLY)
 			return -EROFS;
-		writeback_inodes_sb(sb);
+		/* XFS quotas are fully coherent now, making this call a noop */
 		return 0;
 	default:
 		return -EINVAL;
 	}
 }
 
+#ifdef CONFIG_BLOCK
+
+/* Return 1 if 'cmd' will block on frozen filesystem */
+static int quotactl_cmd_write(int cmd)
+{
+	switch (cmd) {
+	case Q_GETFMT:
+	case Q_GETINFO:
+	case Q_SYNC:
+	case Q_XGETQSTAT:
+	case Q_XGETQSTATV:
+	case Q_XGETQUOTA:
+	case Q_XQUOTASYNC:
+		return 0;
+	}
+	return 1;
+}
+
+#endif /* CONFIG_BLOCK */
+
 /*
  * look up a superblock on which quota ops will be performed
  * - use the name of a block device to find the superblock thereon
  */
-static struct super_block *quotactl_block(const char __user *special)
+static struct super_block *quotactl_block(const char __user *special, int cmd)
 {
 #ifdef CONFIG_BLOCK
 	struct block_device *bdev;
 	struct super_block *sb;
-	char *tmp = getname(special);
+	struct filename *tmp = getname(special);
 
 	if (IS_ERR(tmp))
 		return ERR_CAST(tmp);
-	bdev = lookup_bdev(tmp);
+	bdev = lookup_bdev(tmp->name);
 	putname(tmp);
 	if (IS_ERR(bdev))
 		return ERR_CAST(bdev);
-	sb = get_super(bdev);
+	if (quotactl_cmd_write(cmd))
+		sb = get_super_thawed(bdev);
+	else
+		sb = get_super(bdev);
 	bdput(bdev);
 	if (!sb)
 		return ERR_PTR(-ENODEV);
@@ -314,6 +410,7 @@ SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
 {
 	uint cmds, type;
 	struct super_block *sb = NULL;
+	struct path path, *pathp = NULL;
 	int ret;
 
 	cmds = cmd >> SUBCMDSHIFT;
@@ -330,12 +427,30 @@ SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
 		return -ENODEV;
 	}
 
-	sb = quotactl_block(special);
-	if (IS_ERR(sb))
-		return PTR_ERR(sb);
+	/*
+	 * Path for quotaon has to be resolved before grabbing superblock
+	 * because that gets s_umount sem which is also possibly needed by path
+	 * resolution (think about autofs) and thus deadlocks could arise.
+	 */
+	if (cmds == Q_QUOTAON) {
+		ret = user_path_at(AT_FDCWD, addr, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &path);
+		if (ret)
+			pathp = ERR_PTR(ret);
+		else
+			pathp = &path;
+	}
+
+	sb = quotactl_block(special, cmds);
+	if (IS_ERR(sb)) {
+		ret = PTR_ERR(sb);
+		goto out;
+	}
 
-	ret = do_quotactl(sb, type, cmds, id, addr);
+	ret = do_quotactl(sb, type, cmds, id, addr, pathp);
 
 	drop_super(sb);
+out:
+	if (pathp && !IS_ERR(pathp))
+		path_put(pathp);
 	return ret;
 }