Merge remote-tracking branch 'ovl/misc' into work.misc

fs/attr.c

@@ -202,6 +202,21 @@ int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **de
 			return -EPERM;
 	}
 
+	/*
+	 * If utimes(2) and friends are called with times == NULL (or both
+	 * times are UTIME_NOW), then we need to check for write permission
+	 */
+	if (ia_valid & ATTR_TOUCH) {
+		if (IS_IMMUTABLE(inode))
+			return -EPERM;
+
+		if (!inode_owner_or_capable(inode)) {
+			error = inode_permission(inode, MAY_WRITE);
+			if (error)
+				return error;
+		}
+	}
+
 	if ((ia_valid & ATTR_MODE)) {
 		umode_t amode = attr->ia_mode;
 		/* Flag setting protected by i_mutex */

fs/btrfs/ctree.h

@@ -3161,7 +3161,6 @@ int btrfs_prealloc_file_range_trans(struct inode *inode,
 				    struct btrfs_trans_handle *trans, int mode,
 				    u64 start, u64 num_bytes, u64 min_size,
 				    loff_t actual_len, u64 *alloc_hint);
-int btrfs_inode_check_errors(struct inode *inode);
 extern const struct dentry_operations btrfs_dentry_operations;
 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
 void btrfs_test_inode_set_ops(struct inode *inode);

fs/btrfs/file.c

@@ -2040,7 +2040,7 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 		 * flags for any errors that might have happened while doing
 		 * writeback of file data.
 		 */
-		ret = btrfs_inode_check_errors(inode);
+		ret = filemap_check_errors(inode->i_mapping);
 		inode_unlock(inode);
 		goto out;
 	}

fs/btrfs/inode.c

@@ -10543,21 +10543,6 @@ static int btrfs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
 
 }
 
-/* Inspired by filemap_check_errors() */
-int btrfs_inode_check_errors(struct inode *inode)
-{
-	int ret = 0;
-
-	if (test_bit(AS_ENOSPC, &inode->i_mapping->flags) &&
-	    test_and_clear_bit(AS_ENOSPC, &inode->i_mapping->flags))
-		ret = -ENOSPC;
-	if (test_bit(AS_EIO, &inode->i_mapping->flags) &&
-	    test_and_clear_bit(AS_EIO, &inode->i_mapping->flags))
-		ret = -EIO;
-
-	return ret;
-}
-
 static const struct inode_operations btrfs_dir_inode_operations = {
 	.getattr	= btrfs_getattr,
 	.lookup		= btrfs_lookup,

fs/btrfs/tree-log.c

@@ -3961,7 +3961,7 @@ static int wait_ordered_extents(struct btrfs_trans_handle *trans,
 			 * i_mapping flags, so that the next fsync won't get
 			 * an outdated io error too.
 			 */
-			btrfs_inode_check_errors(inode);
+			filemap_check_errors(inode->i_mapping);
 			*ordered_io_error = true;
 			break;
 		}
@@ -4198,7 +4198,7 @@ static int btrfs_log_changed_extents(struct btrfs_trans_handle *trans,
 	 * without writing to the log tree and the fsync must report the
 	 * file data write error and not commit the current transaction.
 	 */
-	ret = btrfs_inode_check_errors(inode);
+	ret = filemap_check_errors(inode->i_mapping);
 	if (ret)
 		ctx->io_err = ret;
 process:

fs/cifs/cifsfs.h

@@ -41,6 +41,16 @@ cifs_uniqueid_to_ino_t(u64 fileid)
 
 }
 
+static inline void cifs_set_time(struct dentry *dentry, unsigned long time)
+{
+	dentry->d_fsdata = (void *) time;
+}
+
+static inline unsigned long cifs_get_time(struct dentry *dentry)
+{
+	return (unsigned long) dentry->d_fsdata;
+}
+
 extern struct file_system_type cifs_fs_type;
 extern const struct address_space_operations cifs_addr_ops;
 extern const struct address_space_operations cifs_addr_ops_smallbuf;

fs/cifs/dir.c

@@ -40,7 +40,7 @@ renew_parental_timestamps(struct dentry *direntry)
 	/* BB check if there is a way to get the kernel to do this or if we
 	   really need this */
 	do {
-		direntry->d_time = jiffies;
+		cifs_set_time(direntry, jiffies);
 		direntry = direntry->d_parent;
 	} while (!IS_ROOT(direntry));
 }
@@ -802,7 +802,7 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 
 	} else if (rc == -ENOENT) {
 		rc = 0;
-		direntry->d_time = jiffies;
+		cifs_set_time(direntry, jiffies);
 		d_add(direntry, NULL);
 	/*	if it was once a directory (but how can we tell?) we could do
 		shrink_dcache_parent(direntry); */
@@ -862,7 +862,7 @@ cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
 	if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
 		return 0;
 
-	if (time_after(jiffies, direntry->d_time + HZ) || !lookupCacheEnabled)
+	if (time_after(jiffies, cifs_get_time(direntry) + HZ) || !lookupCacheEnabled)
 		return 0;
 
 	return 1;

fs/cifs/inode.c

@@ -1951,7 +1951,7 @@ int cifs_revalidate_dentry_attr(struct dentry *dentry)
 
 	cifs_dbg(FYI, "Update attributes: %s inode 0x%p count %d dentry: 0x%p d_time %ld jiffies %ld\n",
 		 full_path, inode, inode->i_count.counter,
-		 dentry, dentry->d_time, jiffies);
+		 dentry, cifs_get_time(dentry), jiffies);
 
 	if (cifs_sb_master_tcon(CIFS_SB(sb))->unix_ext)
 		rc = cifs_get_inode_info_unix(&inode, full_path, sb, xid);

fs/f2fs/node.c

@@ -1513,7 +1513,7 @@ int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino)
 {
 	pgoff_t index = 0, end = ULONG_MAX;
 	struct pagevec pvec;
-	int ret2 = 0, ret = 0;
+	int ret2, ret = 0;
 
 	pagevec_init(&pvec, 0);
 
@@ -1542,10 +1542,7 @@ int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino)
 		cond_resched();
 	}
 
-	if (unlikely(test_and_clear_bit(AS_ENOSPC, &NODE_MAPPING(sbi)->flags)))
-		ret2 = -ENOSPC;
-	if (unlikely(test_and_clear_bit(AS_EIO, &NODE_MAPPING(sbi)->flags)))
-		ret2 = -EIO;
+	ret2 = filemap_check_errors(NODE_MAPPING(sbi));
 	if (!ret)
 		ret = ret2;
 	return ret;

fs/fat/namei_vfat.c

@@ -21,6 +21,17 @@
 #include <linux/namei.h>
 #include "fat.h"
 
+static inline unsigned long vfat_d_version(struct dentry *dentry)
+{
+	return (unsigned long) dentry->d_fsdata;
+}
+
+static inline void vfat_d_version_set(struct dentry *dentry,
+				      unsigned long version)
+{
+	dentry->d_fsdata = (void *) version;
+}
+
 /*
  * If new entry was created in the parent, it could create the 8.3
  * alias (the shortname of logname).  So, the parent may have the
@@ -33,7 +44,7 @@ static int vfat_revalidate_shortname(struct dentry *dentry)
 {
 	int ret = 1;
 	spin_lock(&dentry->d_lock);
-	if (dentry->d_time != d_inode(dentry->d_parent)->i_version)
+	if (vfat_d_version(dentry) != d_inode(dentry->d_parent)->i_version)
 		ret = 0;
 	spin_unlock(&dentry->d_lock);
 	return ret;
@@ -759,7 +770,7 @@ static struct dentry *vfat_lookup(struct inode *dir, struct dentry *dentry,
 out:
 	mutex_unlock(&MSDOS_SB(sb)->s_lock);
 	if (!inode)
-		dentry->d_time = dir->i_version;
+		vfat_d_version_set(dentry, dir->i_version);
 	return d_splice_alias(inode, dentry);
 error:
 	mutex_unlock(&MSDOS_SB(sb)->s_lock);
@@ -823,7 +834,7 @@ static int vfat_rmdir(struct inode *dir, struct dentry *dentry)
 	clear_nlink(inode);
 	inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC;
 	fat_detach(inode);
-	dentry->d_time = dir->i_version;
+	vfat_d_version_set(dentry, dir->i_version);
 out:
 	mutex_unlock(&MSDOS_SB(sb)->s_lock);
 
@@ -849,7 +860,7 @@ static int vfat_unlink(struct inode *dir, struct dentry *dentry)
 	clear_nlink(inode);
 	inode->i_mtime = inode->i_atime = CURRENT_TIME_SEC;
 	fat_detach(inode);
-	dentry->d_time = dir->i_version;
+	vfat_d_version_set(dentry, dir->i_version);
 out:
 	mutex_unlock(&MSDOS_SB(sb)->s_lock);
 

fs/inode.c

@@ -1562,17 +1562,37 @@ sector_t bmap(struct inode *inode, sector_t block)
 }
 EXPORT_SYMBOL(bmap);
 
+/*
+ * Update times in overlayed inode from underlying real inode
+ */
+static void update_ovl_inode_times(struct dentry *dentry, struct inode *inode,
+			       bool rcu)
+{
+	if (!rcu) {
+		struct inode *realinode = d_real_inode(dentry);
+
+		if (unlikely(inode != realinode) &&
+		    (!timespec_equal(&inode->i_mtime, &realinode->i_mtime) ||
+		     !timespec_equal(&inode->i_ctime, &realinode->i_ctime))) {
+			inode->i_mtime = realinode->i_mtime;
+			inode->i_ctime = realinode->i_ctime;
+		}
+	}
+}
+
 /*
  * With relative atime, only update atime if the previous atime is
  * earlier than either the ctime or mtime or if at least a day has
  * passed since the last atime update.
  */
-static int relatime_need_update(struct vfsmount *mnt, struct inode *inode,
-			     struct timespec now)
+static int relatime_need_update(const struct path *path, struct inode *inode,
+				struct timespec now, bool rcu)
 {
 
-	if (!(mnt->mnt_flags & MNT_RELATIME))
+	if (!(path->mnt->mnt_flags & MNT_RELATIME))
 		return 1;
+
+	update_ovl_inode_times(path->dentry, inode, rcu);
 	/*
 	 * Is mtime younger than atime? If yes, update atime:
 	 */
@@ -1639,7 +1659,8 @@ static int update_time(struct inode *inode, struct timespec *time, int flags)
  *	This function automatically handles read only file systems and media,
  *	as well as the "noatime" flag and inode specific "noatime" markers.
  */
-bool atime_needs_update(const struct path *path, struct inode *inode)
+bool __atime_needs_update(const struct path *path, struct inode *inode,
+			  bool rcu)
 {
 	struct vfsmount *mnt = path->mnt;
 	struct timespec now;
@@ -1665,7 +1686,7 @@ bool atime_needs_update(const struct path *path, struct inode *inode)
 
 	now = current_fs_time(inode->i_sb);
 
-	if (!relatime_need_update(mnt, inode, now))
+	if (!relatime_need_update(path, inode, now, rcu))
 		return false;
 
 	if (timespec_equal(&inode->i_atime, &now))
@@ -1680,7 +1701,7 @@ void touch_atime(const struct path *path)
 	struct inode *inode = d_inode(path->dentry);
 	struct timespec now;
 
-	if (!atime_needs_update(path, inode))
+	if (!__atime_needs_update(path, inode, false))
 		return;
 
 	if (!sb_start_write_trylock(inode->i_sb))

fs/internal.h

@@ -120,6 +120,15 @@ extern long prune_icache_sb(struct super_block *sb, struct shrink_control *sc);
 extern void inode_add_lru(struct inode *inode);
 extern int dentry_needs_remove_privs(struct dentry *dentry);
 
+extern bool __atime_needs_update(const struct path *, struct inode *, bool);
+static inline bool atime_needs_update_rcu(const struct path *path,
+					  struct inode *inode)
+{
+	return __atime_needs_update(path, inode, true);
+}
+
+extern bool atime_needs_update_rcu(const struct path *, struct inode *);
+
 /*
  * fs-writeback.c
  */

fs/locks.c

@@ -139,6 +139,11 @@
 #define IS_LEASE(fl)	(fl->fl_flags & (FL_LEASE|FL_DELEG|FL_LAYOUT))
 #define IS_OFDLCK(fl)	(fl->fl_flags & FL_OFDLCK)
 
+static inline bool is_remote_lock(struct file *filp)
+{
+	return likely(!(filp->f_path.dentry->d_sb->s_flags & MS_NOREMOTELOCK));
+}
+
 static bool lease_breaking(struct file_lock *fl)
 {
 	return fl->fl_flags & (FL_UNLOCK_PENDING | FL_DOWNGRADE_PENDING);
@@ -791,7 +796,7 @@ posix_test_lock(struct file *filp, struct file_lock *fl)
 {
 	struct file_lock *cfl;
 	struct file_lock_context *ctx;
-	struct inode *inode = file_inode(filp);
+	struct inode *inode = locks_inode(filp);
 
 	ctx = smp_load_acquire(&inode->i_flctx);
 	if (!ctx || list_empty_careful(&ctx->flc_posix)) {
@@ -1192,7 +1197,7 @@ static int posix_lock_inode(struct inode *inode, struct file_lock *request,
 int posix_lock_file(struct file *filp, struct file_lock *fl,
 			struct file_lock *conflock)
 {
-	return posix_lock_inode(file_inode(filp), fl, conflock);
+	return posix_lock_inode(locks_inode(filp), fl, conflock);
 }
 EXPORT_SYMBOL(posix_lock_file);
 
@@ -1232,7 +1237,7 @@ static int posix_lock_inode_wait(struct inode *inode, struct file_lock *fl)
 int locks_mandatory_locked(struct file *file)
 {
 	int ret;
-	struct inode *inode = file_inode(file);
+	struct inode *inode = locks_inode(file);
 	struct file_lock_context *ctx;
 	struct file_lock *fl;
 
@@ -1572,7 +1577,7 @@ EXPORT_SYMBOL(lease_get_mtime);
 int fcntl_getlease(struct file *filp)
 {
 	struct file_lock *fl;
-	struct inode *inode = file_inode(filp);
+	struct inode *inode = locks_inode(filp);
 	struct file_lock_context *ctx;
 	int type = F_UNLCK;
 	LIST_HEAD(dispose);
@@ -1580,7 +1585,7 @@ int fcntl_getlease(struct file *filp)
 	ctx = smp_load_acquire(&inode->i_flctx);
 	if (ctx && !list_empty_careful(&ctx->flc_lease)) {
 		spin_lock(&ctx->flc_lock);
-		time_out_leases(file_inode(filp), &dispose);
+		time_out_leases(inode, &dispose);
 		list_for_each_entry(fl, &ctx->flc_lease, fl_list) {
 			if (fl->fl_file != filp)
 				continue;
@@ -1613,7 +1618,8 @@ check_conflicting_open(const struct dentry *dentry, const long arg, int flags)
 	if (flags & FL_LAYOUT)
 		return 0;
 
-	if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
+	if ((arg == F_RDLCK) &&
+	    (atomic_read(&d_real_inode(dentry)->i_writecount) > 0))
 		return -EAGAIN;
 
 	if ((arg == F_WRLCK) && ((d_count(dentry) > 1) ||
@@ -1628,7 +1634,7 @@ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr
 {
 	struct file_lock *fl, *my_fl = NULL, *lease;
 	struct dentry *dentry = filp->f_path.dentry;
-	struct inode *inode = file_inode(filp);
+	struct inode *inode = dentry->d_inode;
 	struct file_lock_context *ctx;
 	bool is_deleg = (*flp)->fl_flags & FL_DELEG;
 	int error;
@@ -1742,7 +1748,7 @@ static int generic_delete_lease(struct file *filp, void *owner)
 {
 	int error = -EAGAIN;
 	struct file_lock *fl, *victim = NULL;
-	struct inode *inode = file_inode(filp);
+	struct inode *inode = locks_inode(filp);
 	struct file_lock_context *ctx;
 	LIST_HEAD(dispose);
 
@@ -1782,7 +1788,7 @@ static int generic_delete_lease(struct file *filp, void *owner)
 int generic_setlease(struct file *filp, long arg, struct file_lock **flp,
 			void **priv)
 {
-	struct inode *inode = file_inode(filp);
+	struct inode *inode = locks_inode(filp);
 	int error;
 
 	if ((!uid_eq(current_fsuid(), inode->i_uid)) && !capable(CAP_LEASE))
@@ -1830,7 +1836,7 @@ EXPORT_SYMBOL(generic_setlease);
 int
 vfs_setlease(struct file *filp, long arg, struct file_lock **lease, void **priv)
 {
-	if (filp->f_op->setlease)
+	if (filp->f_op->setlease && is_remote_lock(filp))
 		return filp->f_op->setlease(filp, arg, lease, priv);
 	else
 		return generic_setlease(filp, arg, lease, priv);
@@ -1979,7 +1985,7 @@ SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd)
 	if (error)
 		goto out_free;
 
-	if (f.file->f_op->flock)
+	if (f.file->f_op->flock && is_remote_lock(f.file))
 		error = f.file->f_op->flock(f.file,
 					  (can_sleep) ? F_SETLKW : F_SETLK,
 					  lock);
@@ -2005,7 +2011,7 @@ SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd)
  */
 int vfs_test_lock(struct file *filp, struct file_lock *fl)
 {
-	if (filp->f_op->lock)
+	if (filp->f_op->lock && is_remote_lock(filp))
 		return filp->f_op->lock(filp, F_GETLK, fl);
 	posix_test_lock(filp, fl);
 	return 0;
@@ -2129,7 +2135,7 @@ int fcntl_getlk(struct file *filp, unsigned int cmd, struct flock __user *l)
  */
 int vfs_lock_file(struct file *filp, unsigned int cmd, struct file_lock *fl, struct file_lock *conf)
 {
-	if (filp->f_op->lock)
+	if (filp->f_op->lock && is_remote_lock(filp))
 		return filp->f_op->lock(filp, cmd, fl);
 	else
 		return posix_lock_file(filp, fl, conf);
@@ -2191,7 +2197,7 @@ int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
 	if (file_lock == NULL)
 		return -ENOLCK;
 
-	inode = file_inode(filp);
+	inode = locks_inode(filp);
 
 	/*
 	 * This might block, so we do it before checking the inode.
@@ -2343,7 +2349,7 @@ int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd,
 	if (copy_from_user(&flock, l, sizeof(flock)))
 		goto out;
 
-	inode = file_inode(filp);
+	inode = locks_inode(filp);
 
 	/* Don't allow mandatory locks on files that may be memory mapped
 	 * and shared.
@@ -2426,6 +2432,7 @@ int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd,
 void locks_remove_posix(struct file *filp, fl_owner_t owner)
 {
 	int error;
+	struct inode *inode = locks_inode(filp);
 	struct file_lock lock;
 	struct file_lock_context *ctx;
 
@@ -2434,7 +2441,7 @@ void locks_remove_posix(struct file *filp, fl_owner_t owner)
 	 * posix_lock_file().  Another process could be setting a lock on this
 	 * file at the same time, but we wouldn't remove that lock anyway.
 	 */
-	ctx =  smp_load_acquire(&file_inode(filp)->i_flctx);
+	ctx =  smp_load_acquire(&inode->i_flctx);
 	if (!ctx || list_empty(&ctx->flc_posix))
 		return;
 
@@ -2452,7 +2459,7 @@ void locks_remove_posix(struct file *filp, fl_owner_t owner)
 
 	if (lock.fl_ops && lock.fl_ops->fl_release_private)
 		lock.fl_ops->fl_release_private(&lock);
-	trace_locks_remove_posix(file_inode(filp), &lock, error);
+	trace_locks_remove_posix(inode, &lock, error);
 }
 
 EXPORT_SYMBOL(locks_remove_posix);
@@ -2469,12 +2476,12 @@ locks_remove_flock(struct file *filp, struct file_lock_context *flctx)
 		.fl_type = F_UNLCK,
 		.fl_end = OFFSET_MAX,
 	};
-	struct inode *inode = file_inode(filp);
+	struct inode *inode = locks_inode(filp);
 
 	if (list_empty(&flctx->flc_flock))
 		return;
 
-	if (filp->f_op->flock)
+	if (filp->f_op->flock && is_remote_lock(filp))
 		filp->f_op->flock(filp, F_SETLKW, &fl);
 	else
 		flock_lock_inode(inode, &fl);
@@ -2508,7 +2515,7 @@ void locks_remove_file(struct file *filp)
 {
 	struct file_lock_context *ctx;
 
-	ctx = smp_load_acquire(&file_inode(filp)->i_flctx);
+	ctx = smp_load_acquire(&locks_inode(filp)->i_flctx);
 	if (!ctx)
 		return;
 
@@ -2552,7 +2559,7 @@ EXPORT_SYMBOL(posix_unblock_lock);
  */
 int vfs_cancel_lock(struct file *filp, struct file_lock *fl)
 {
-	if (filp->f_op->lock)
+	if (filp->f_op->lock && is_remote_lock(filp))
 		return filp->f_op->lock(filp, F_CANCELLK, fl);
 	return 0;
 }
@@ -2580,7 +2587,7 @@ static void lock_get_status(struct seq_file *f, struct file_lock *fl,
 		fl_pid = fl->fl_pid;
 
 	if (fl->fl_file != NULL)
-		inode = file_inode(fl->fl_file);
+		inode = locks_inode(fl->fl_file);
 
 	seq_printf(f, "%lld:%s ", id, pfx);
 	if (IS_POSIX(fl)) {
@@ -2682,7 +2689,7 @@ static void __show_fd_locks(struct seq_file *f,
 void show_fd_locks(struct seq_file *f,
 		  struct file *filp, struct files_struct *files)
 {
-	struct inode *inode = file_inode(filp);
+	struct inode *inode = locks_inode(filp);
 	struct file_lock_context *ctx;
 	int id = 0;
 

fs/namei.c

@@ -1015,7 +1015,7 @@ const char *get_link(struct nameidata *nd)
 	if (!(nd->flags & LOOKUP_RCU)) {
 		touch_atime(&last->link);
 		cond_resched();
-	} else if (atime_needs_update(&last->link, inode)) {
+	} else if (atime_needs_update_rcu(&last->link, inode)) {
 		if (unlikely(unlazy_walk(nd, NULL, 0)))
 			return ERR_PTR(-ECHILD);
 		touch_atime(&last->link);

fs/namespace.c

@@ -2700,7 +2700,7 @@ long do_mount(const char *dev_name, const char __user *dir_name,
 
 	flags &= ~(MS_NOSUID | MS_NOEXEC | MS_NODEV | MS_ACTIVE | MS_BORN |
 		   MS_NOATIME | MS_NODIRATIME | MS_RELATIME| MS_KERNMOUNT |
-		   MS_STRICTATIME);
+		   MS_STRICTATIME | MS_NOREMOTELOCK);
 
 	if (flags & MS_REMOUNT)
 		retval = do_remount(&path, flags & ~MS_REMOUNT, mnt_flags,

fs/open.c

@@ -68,6 +68,7 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
 long vfs_truncate(const struct path *path, loff_t length)
 {
 	struct inode *inode;
+	struct dentry *upperdentry;
 	long error;
 
 	inode = path->dentry->d_inode;
@@ -90,7 +91,17 @@ long vfs_truncate(const struct path *path, loff_t length)
 	if (IS_APPEND(inode))
 		goto mnt_drop_write_and_out;
 
-	error = get_write_access(inode);
+	/*
+	 * If this is an overlayfs then do as if opening the file so we get
+	 * write access on the upper inode, not on the overlay inode.  For
+	 * non-overlay filesystems d_real() is an identity function.
+	 */
+	upperdentry = d_real(path->dentry, NULL, O_WRONLY);
+	error = PTR_ERR(upperdentry);
+	if (IS_ERR(upperdentry))
+		goto mnt_drop_write_and_out;
+
+	error = get_write_access(upperdentry->d_inode);
 	if (error)
 		goto mnt_drop_write_and_out;
 
@@ -109,7 +120,7 @@ long vfs_truncate(const struct path *path, loff_t length)
 		error = do_truncate(path->dentry, length, 0, NULL);
 
 put_write_and_out:
-	put_write_access(inode);
+	put_write_access(upperdentry->d_inode);
 mnt_drop_write_and_out:
 	mnt_drop_write(path->mnt);
 out:
@@ -726,7 +737,7 @@ static int do_dentry_open(struct file *f,
 	if (error)
 		goto cleanup_all;
 
-	error = break_lease(inode, f->f_flags);
+	error = break_lease(locks_inode(f), f->f_flags);
 	if (error)
 		goto cleanup_all;
 

fs/overlayfs/super.c

@@ -1320,7 +1320,7 @@ static int ovl_fill_super(struct super_block *sb, void *data, int silent)
 	sb->s_xattr = ovl_xattr_handlers;
 	sb->s_root = root_dentry;
 	sb->s_fs_info = ufs;
-	sb->s_flags |= MS_POSIXACL;
+	sb->s_flags |= MS_POSIXACL | MS_NOREMOTELOCK;
 
 	return 0;
 

fs/posix_acl.c

@@ -598,13 +598,14 @@ posix_acl_create(struct inode *dir, umode_t *mode,
 	if (IS_ERR(p))
 		return PTR_ERR(p);
 
+	ret = -ENOMEM;
 	clone = posix_acl_clone(p, GFP_NOFS);
 	if (!clone)
-		goto no_mem;
+		goto err_release;
 
 	ret = posix_acl_create_masq(clone, mode);
 	if (ret < 0)
-		goto no_mem_clone;
+		goto err_release_clone;
 
 	if (ret == 0)
 		posix_acl_release(clone);
@@ -618,11 +619,11 @@ posix_acl_create(struct inode *dir, umode_t *mode,
 
 	return 0;
 
-no_mem_clone:
+err_release_clone:
 	posix_acl_release(clone);
-no_mem:
+err_release:
 	posix_acl_release(p);
-	return -ENOMEM;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(posix_acl_create);
 

fs/utimes.c

@@ -87,21 +87,7 @@ static int utimes_common(struct path *path, struct timespec *times)
 		 */
 		newattrs.ia_valid |= ATTR_TIMES_SET;
 	} else {
-		/*
-		 * If times is NULL (or both times are UTIME_NOW),
-		 * then we need to check permissions, because
-		 * inode_change_ok() won't do it.
-		 */
-		error = -EPERM;
-                if (IS_IMMUTABLE(inode))
-			goto mnt_drop_write_and_out;
-
-		error = -EACCES;
-		if (!inode_owner_or_capable(inode)) {
-			error = inode_permission(inode, MAY_WRITE);
-			if (error)
-				goto mnt_drop_write_and_out;
-		}
+		newattrs.ia_valid |= ATTR_TOUCH;
 	}
 retry_deleg:
 	inode_lock(inode);
@@ -113,7 +99,6 @@ static int utimes_common(struct path *path, struct timespec *times)
 			goto retry_deleg;
 	}
 
-mnt_drop_write_and_out:
 	mnt_drop_write(path->mnt);
 out:
 	return error;

include/linux/dcache.h

@@ -584,9 +584,10 @@ static inline struct dentry *d_real(struct dentry *dentry,
  * If dentry is on an union/overlay, then return the underlying, real inode.
  * Otherwise return d_inode().
  */
-static inline struct inode *d_real_inode(struct dentry *dentry)
+static inline struct inode *d_real_inode(const struct dentry *dentry)
 {
-	return d_backing_inode(d_real(dentry, NULL, 0));
+	/* This usage of d_real() results in const dentry */
+	return d_backing_inode(d_real((struct dentry *) dentry, NULL, 0));
 }
 
 

include/linux/fs.h

@@ -224,6 +224,7 @@ typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset,
 #define ATTR_KILL_PRIV	(1 << 14)
 #define ATTR_OPEN	(1 << 15) /* Truncating from open(O_TRUNC) */
 #define ATTR_TIMES_SET	(1 << 16)
+#define ATTR_TOUCH	(1 << 17)
 
 /*
  * Whiteout is represented by a char device.  The following constants define the
@@ -1064,6 +1065,18 @@ struct file_lock_context {
 
 extern void send_sigio(struct fown_struct *fown, int fd, int band);
 
+/*
+ * Return the inode to use for locking
+ *
+ * For overlayfs this should be the overlay inode, not the real inode returned
+ * by file_inode().  For any other fs file_inode(filp) and locks_inode(filp) are
+ * equal.
+ */
+static inline struct inode *locks_inode(const struct file *f)
+{
+	return f->f_path.dentry->d_inode;
+}
+
 #ifdef CONFIG_FILE_LOCKING
 extern int fcntl_getlk(struct file *, unsigned int, struct flock __user *);
 extern int fcntl_setlk(unsigned int, struct file *, unsigned int,
@@ -1251,7 +1264,7 @@ static inline struct dentry *file_dentry(const struct file *file)
 
 static inline int locks_lock_file_wait(struct file *filp, struct file_lock *fl)
 {
-	return locks_lock_inode_wait(file_inode(filp), fl);
+	return locks_lock_inode_wait(locks_inode(filp), fl);
 }
 
 struct fasync_struct {
@@ -2006,7 +2019,6 @@ enum file_time_flags {
 	S_VERSION = 8,
 };
 
-extern bool atime_needs_update(const struct path *, struct inode *);
 extern void touch_atime(const struct path *);
 static inline void file_accessed(struct file *file)
 {
@@ -2155,7 +2167,7 @@ static inline int mandatory_lock(struct inode *ino)
 
 static inline int locks_verify_locked(struct file *file)
 {
-	if (mandatory_lock(file_inode(file)))
+	if (mandatory_lock(locks_inode(file)))
 		return locks_mandatory_locked(file);
 	return 0;
 }

include/linux/fsnotify.h

@@ -29,7 +29,11 @@ static inline int fsnotify_parent(struct path *path, struct dentry *dentry, __u3
 static inline int fsnotify_perm(struct file *file, int mask)
 {
 	struct path *path = &file->f_path;
-	struct inode *inode = file_inode(file);
+	/*
+	 * Do not use file_inode() here or anywhere in this file to get the
+	 * inode.  That would break *notity on overlayfs.
+	 */
+	struct inode *inode = path->dentry->d_inode;
 	__u32 fsnotify_mask = 0;
 	int ret;
 
@@ -173,7 +177,7 @@ static inline void fsnotify_mkdir(struct inode *inode, struct dentry *dentry)
 static inline void fsnotify_access(struct file *file)
 {
 	struct path *path = &file->f_path;
-	struct inode *inode = file_inode(file);
+	struct inode *inode = path->dentry->d_inode;
 	__u32 mask = FS_ACCESS;
 
 	if (S_ISDIR(inode->i_mode))
@@ -191,7 +195,7 @@ static inline void fsnotify_access(struct file *file)
 static inline void fsnotify_modify(struct file *file)
 {
 	struct path *path = &file->f_path;
-	struct inode *inode = file_inode(file);
+	struct inode *inode = path->dentry->d_inode;
 	__u32 mask = FS_MODIFY;
 
 	if (S_ISDIR(inode->i_mode))
@@ -209,7 +213,7 @@ static inline void fsnotify_modify(struct file *file)
 static inline void fsnotify_open(struct file *file)
 {
 	struct path *path = &file->f_path;
-	struct inode *inode = file_inode(file);
+	struct inode *inode = path->dentry->d_inode;
 	__u32 mask = FS_OPEN;
 
 	if (S_ISDIR(inode->i_mode))
@@ -225,7 +229,7 @@ static inline void fsnotify_open(struct file *file)
 static inline void fsnotify_close(struct file *file)
 {
 	struct path *path = &file->f_path;
-	struct inode *inode = file_inode(file);
+	struct inode *inode = path->dentry->d_inode;
 	fmode_t mode = file->f_mode;
 	__u32 mask = (mode & FMODE_WRITE) ? FS_CLOSE_WRITE : FS_CLOSE_NOWRITE;
 

include/uapi/linux/fs.h

@@ -132,6 +132,7 @@ struct inodes_stat_t {
 #define MS_LAZYTIME	(1<<25) /* Update the on-disk [acm]times lazily */
 
 /* These sb flags are internal to the kernel */
+#define MS_NOREMOTELOCK	(1<<27)
 #define MS_NOSEC	(1<<28)
 #define MS_BORN		(1<<29)
 #define MS_ACTIVE	(1<<30)

security/integrity/ima/ima_appraise.c

@@ -190,7 +190,7 @@ int ima_appraise_measurement(enum ima_hooks func,
 {
 	static const char op[] = "appraise_data";
 	char *cause = "unknown";
-	struct dentry *dentry = file->f_path.dentry;
+	struct dentry *dentry = file_dentry(file);
 	struct inode *inode = d_backing_inode(dentry);
 	enum integrity_status status = INTEGRITY_UNKNOWN;
 	int rc = xattr_len, hash_start = 0;
@@ -295,7 +295,7 @@ int ima_appraise_measurement(enum ima_hooks func,
  */
 void ima_update_xattr(struct integrity_iint_cache *iint, struct file *file)
 {
-	struct dentry *dentry = file->f_path.dentry;
+	struct dentry *dentry = file_dentry(file);
 	int rc = 0;
 
 	/* do not collect and update hash for digital signatures */

security/integrity/ima/ima_main.c

@@ -228,7 +228,7 @@ static int process_measurement(struct file *file, char *buf, loff_t size,
 	if ((action & IMA_APPRAISE_SUBMASK) ||
 		    strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) != 0)
 		/* read 'security.ima' */
-		xattr_len = ima_read_xattr(file->f_path.dentry, &xattr_value);
+		xattr_len = ima_read_xattr(file_dentry(file), &xattr_value);
 
 	hash_algo = ima_get_hash_algo(xattr_value, xattr_len);