pipe: return -ENOIOCTLCMD instead of -EINVAL on unknown ioctl command

As described in commit 07d106d0a ("vfs: fix up ENOIOCTLCMD error handling"), drivers should return -ENOIOCTLCMD if they receive an ioctl command which they don't understand. Doing so will result in -ENOTTY being returned to userspace, which matches the behaviour of the compat layer if it fails to translate an ioctl command.

This patch fixes the pipe ioctl to return -ENOIOCTLCMD instead of -EINVAL when passed an unknown ioctl command.

---
 fs/pipe.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

index fec5e4a..95ebb56 100644
@@ -693,7 +693,7 @@ static long pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 
 			return put_user(count, (int __user *)arg);
 		default:
-			return -EINVAL;
+			return -ENOIOCTLCMD;
 	}
 }
 

1.7.4.1