3 files changed, 20 insertions, 9 deletions

diff --git a/fs/aio.c b/fs/aio.c
index f8e52a1854c1..58c33dcfb6ca 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -278,11 +278,11 @@ static int aio_ring_mmap(struct file *file, struct vm_area_struct *vma)
         return 0;
 }
 
-static void aio_ring_remap(struct file *file, struct vm_area_struct *vma)
+static int aio_ring_remap(struct file *file, struct vm_area_struct *vma)
 {
         struct mm_struct *mm = vma->vm_mm;
         struct kioctx_table *table;
-        int i;
+        int i, res = -EINVAL;
 
         spin_lock(&mm->ioctx_lock);
         rcu_read_lock();
@@ -292,13 +292,17 @@ static void aio_ring_remap(struct file *file, struct vm_area_struct *vma)
 
                 ctx = table->table[i];
                 if (ctx && ctx->aio_ring_file == file) {
-                        ctx->user_id = ctx->mmap_base = vma->vm_start;
+                        if (!atomic_read(&ctx->dead)) {
+                                ctx->user_id = ctx->mmap_base = vma->vm_start;
+                                res = 0;
+                        }
                         break;
                 }
         }
 
         rcu_read_unlock();
         spin_unlock(&mm->ioctx_lock);
+        return res;
 }
 
 static const struct file_operations aio_ring_fops = {
@@ -748,11 +752,12 @@ static int kill_ioctx(struct mm_struct *mm, struct kioctx *ctx,
 {
         struct kioctx_table *table;
 
-        if (atomic_xchg(&ctx->dead, 1))
+        spin_lock(&mm->ioctx_lock);
+        if (atomic_xchg(&ctx->dead, 1)) {
+                spin_unlock(&mm->ioctx_lock);
                 return -EINVAL;
+        }
 
-
-        spin_lock(&mm->ioctx_lock);
         table = rcu_dereference_raw(mm->ioctx_table);
         WARN_ON(ctx != table->table[ctx->id]);
         table->table[ctx->id] = NULL;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index f4131e8ead74..52cc4492cb3a 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1549,7 +1549,7 @@ struct file_operations {
         long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
         long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
         int (*mmap) (struct file *, struct vm_area_struct *);
-        void (*mremap)(struct file *, struct vm_area_struct *);
+        int (*mremap)(struct file *, struct vm_area_struct *);
         int (*open) (struct inode *, struct file *);
         int (*flush) (struct file *, fl_owner_t id);
         int (*release) (struct inode *, struct file *);
diff --git a/mm/mremap.c b/mm/mremap.c
index 57dadc025c64..2dc44b1cb1df 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -286,8 +286,14 @@ static unsigned long move_vma(struct vm_area_struct *vma,
                 old_len = new_len;
                 old_addr = new_addr;
                 new_addr = -ENOMEM;
-        } else if (vma->vm_file && vma->vm_file->f_op->mremap)
-                vma->vm_file->f_op->mremap(vma->vm_file, new_vma);
+        } else if (vma->vm_file && vma->vm_file->f_op->mremap) {
+                err = vma->vm_file->f_op->mremap(vma->vm_file, new_vma);
+                if (err < 0) {
+                        move_page_tables(new_vma, new_addr, vma, old_addr,
+                                         moved_len, true);
+                        return err;
+                }
+        }
 
         /* Conceal VM_ACCOUNT so old reservation is not undone */
         if (vm_flags & VM_ACCOUNT) {