6 files changed, 46 insertions, 27 deletions

diff --git a/fs/locks.c b/fs/locks.c
index ee1b15f6fc13..c1656cff53ee 100644
--- a/fs/locks.c
+++ b/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;
@@ -1628,7 +1633,7 @@ 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 +1747,7 @@ 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 +1787,7 @@ 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 +1835,7 @@ 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 +1984,7 @@ 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 +2010,7 @@ 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 +2134,7 @@ out:
  */
 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 +2196,7 @@ 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 +2348,7 @@ 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 +2431,7 @@ out:
 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 +2440,7 @@ 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 +2458,7 @@ 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 +2475,12 @@ 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 +2514,7 @@ 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 +2558,7 @@ 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 +2586,7 @@ 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 +2688,7 @@ 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;
 
diff --git a/fs/namespace.c b/fs/namespace.c
index 7bb2cda3bfef..dcd9afe21e62 100644
--- a/fs/namespace.c
+++ b/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,
diff --git a/fs/open.c b/fs/open.c
index 4fd6e256f4f4..648fb9d3e97a 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -726,7 +726,7 @@ 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;
 
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index e2a94a26767b..3d0b9dee2b76 100644
--- a/fs/overlayfs/super.c
+++ b/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;
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 7db097d673a8..8ee0f011547f 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1065,6 +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,
@@ -1252,7 +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 {
@@ -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;
 }
diff --git a/include/uapi/linux/fs.h b/include/uapi/linux/fs.h
index 3b00f7c8943f..2473272169f2 100644
--- a/include/uapi/linux/fs.h
+++ b/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)