3 files changed, 13 insertions, 2 deletions

diff --git a/fs/autofs4/autofs_i.h b/fs/autofs4/autofs_i.h
index d8d8e7ba6a1e..908e18455413 100644
--- a/fs/autofs4/autofs_i.h
+++ b/fs/autofs4/autofs_i.h
@@ -269,6 +269,17 @@ int autofs4_fill_super(struct super_block *, void *, int);
 struct autofs_info *autofs4_new_ino(struct autofs_sb_info *);
 void autofs4_clean_ino(struct autofs_info *);
 
+static inline int autofs_prepare_pipe(struct file *pipe)
+{
+        if (!pipe->f_op || !pipe->f_op->write)
+                return -EINVAL;
+        if (!S_ISFIFO(pipe->f_dentry->d_inode->i_mode))
+                return -EINVAL;
+        /* We want a packet pipe */
+        pipe->f_flags |= O_DIRECT;
+        return 0;
+}
+
 /* Queue management functions */
 
 int autofs4_wait(struct autofs_sb_info *,struct dentry *, enum autofs_notify);
diff --git a/fs/autofs4/dev-ioctl.c b/fs/autofs4/dev-ioctl.c
index 3dfd615afb6b..aa9103f8f01b 100644
--- a/fs/autofs4/dev-ioctl.c
+++ b/fs/autofs4/dev-ioctl.c
@@ -376,7 +376,7 @@ static int autofs_dev_ioctl_setpipefd(struct file *fp,
                         err = -EBADF;
                         goto out;
                 }
-                if (!pipe->f_op || !pipe->f_op->write) {
+                if (autofs_prepare_pipe(pipe) < 0) {
                         err = -EPIPE;
                         fput(pipe);
                         goto out;
diff --git a/fs/autofs4/inode.c b/fs/autofs4/inode.c
index 14c7bc02349e..6e488ebe7784 100644
--- a/fs/autofs4/inode.c
+++ b/fs/autofs4/inode.c
@@ -290,7 +290,7 @@ int autofs4_fill_super(struct super_block *s, void *data, int silent)
                 printk("autofs: could not open pipe file descriptor\n");
                 goto fail_dput;
         }
-        if (!pipe->f_op || !pipe->f_op->write)
+        if (autofs_prepare_pipe(pipe) < 0)
                 goto fail_fput;
         sbi->pipe = pipe;
         sbi->pipefd = pipefd;