[Devel] [PATCH v2] fs/fuse kio: deny unavailable ioctl's in kio

[Pavel Butsykin]

There are some ioctl's that were made to service the kio module, and they
should not be available to user app.

Also there are two ioctls PCS_IOC_NOCSUMONREAD and PCS_IOC_NOWRITEDELAY that
must be handled in kio, otherwise they are meaningless. So let's return
-EOPNOTSUPP unless we implement them in kio.

Signed-off-by: Pavel Butsykin <pbutsykin at virtuozzo.com>
---
 fs/fuse/fuse_i.h                   |  2 ++
 fs/fuse/kio/pcs/pcs_fuse_kdirect.c | 27 ++++++++++++++++++++++++---
 fs/fuse/kio/pcs/pcs_ioctl.h        |  5 +++++
 3 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index d7dd571c08f6..4c27bfa0e74d 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -301,6 +301,7 @@ struct fuse_io_priv {
  * FR_FINISHED:		request is finished
  * FR_PRIVATE:		request is on private list
  * FR_NONBLOCKING:	non-blocking request (only needed for KIO)
+ * FR_KIO_INTERNAL:	request initiated by KIO
  */
 enum fuse_req_flag {
 	FR_ISREPLY,
@@ -315,6 +316,7 @@ enum fuse_req_flag {
 	FR_FINISHED,
 	FR_PRIVATE,
 	FR_NONBLOCKING,
+	FR_KIO_INTERNAL,
 };
 
 /**
diff --git a/fs/fuse/kio/pcs/pcs_fuse_kdirect.c b/fs/fuse/kio/pcs/pcs_fuse_kdirect.c
index 89866370a341..cdd4fe578128 100644
--- a/fs/fuse/kio/pcs/pcs_fuse_kdirect.c
+++ b/fs/fuse/kio/pcs/pcs_fuse_kdirect.c
@@ -156,6 +156,7 @@ int kpcs_conn_init(struct fuse_conn *fc)
 	}
 
 	__set_bit(FR_BACKGROUND, &req->flags);
+	__set_bit(FR_KIO_INTERNAL, &req->flags);
 	memset(&req->misc.ioctl, 0, sizeof(req->misc.ioctl));
 	/* filehandle and nodeid are null, but this is OK */
 	inarg = &req->misc.ioctl.in;
@@ -218,6 +219,7 @@ static int fuse_pcs_getfileinfo(struct fuse_conn *fc, struct file *file,
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
+	__set_bit(FR_KIO_INTERNAL, &req->flags);
 	memset(&req->misc.ioctl, 0, sizeof(req->misc.ioctl));
 	inarg = &req->misc.ioctl.in;
 	outarg = &req->misc.ioctl.out;
@@ -269,6 +271,7 @@ static int fuse_pcs_kdirect_claim_op(struct fuse_conn *fc, struct file *file,
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
+	__set_bit(FR_KIO_INTERNAL, &req->flags);
 	memset(&req->misc.ioctl, 0, sizeof(req->misc.ioctl));
 	inarg = &req->misc.ioctl.in;
 	outarg = &req->misc.ioctl.out;
@@ -470,6 +473,7 @@ int fuse_map_resolve(struct pcs_map_entry *m, int direction)
 		return PTR_ERR(req);
 	}
 
+	__set_bit(FR_KIO_INTERNAL, &req->flags);
 	memset(&req->misc.ioctl, 0, sizeof(req->misc.ioctl));
 	inarg = &req->misc.ioctl.in;
 	outarg = &req->misc.ioctl.out;
@@ -601,6 +605,7 @@ int fuse_pcs_csconn_send(struct fuse_conn *fc, struct pcs_rpc *ep, int flags)
 		return PTR_ERR(req);
 	}
 
+	__set_bit(FR_KIO_INTERNAL, &req->flags);
 	memset(&req->misc.ioctl, 0, sizeof(req->misc.ioctl));
 	inarg = &req->misc.ioctl.in;
 	outarg = &req->misc.ioctl.out;
@@ -1084,6 +1089,9 @@ static int pcs_kio_classify_req(struct fuse_conn *fc, struct fuse_req *req, bool
 {
 	struct fuse_inode *fi = get_fuse_inode(req->io_inode);
 
+	if (test_bit(FR_KIO_INTERNAL, &req->flags))
+		return 1;
+
 	switch (req->in.h.opcode) {
 	case FUSE_READ:
 	case FUSE_WRITE:
@@ -1110,9 +1118,22 @@ static int pcs_kio_classify_req(struct fuse_conn *fc, struct fuse_req *req, bool
 	case FUSE_IOCTL: {
 		struct fuse_ioctl_in const *inarg = req->in.args[0].value;
 
-		if (inarg->cmd != FS_IOC_FIEMAP)
-			return 1;
-
+		switch (inarg->cmd) {
+			case FS_IOC_FIEMAP:
+				break;
+			case PCS_IOC_NOCSUMONREAD:
+			case PCS_IOC_NOWRITEDELAY:
+				return -EOPNOTSUPP;
+			case PCS_IOC_INIT_KDIRECT:
+			case PCS_IOC_CSCONN:
+			case PCS_IOC_GETFILEINFO:
+			case PCS_IOC_KDIRECT_CLAIM:
+			case PCS_IOC_KDIRECT_RELEASE:
+			case PCS_IOC_GETMAP:
+				return -EPERM;
+			default:
+				return 1;
+		}
 		break;
 	}
 	default:
diff --git a/fs/fuse/kio/pcs/pcs_ioctl.h b/fs/fuse/kio/pcs/pcs_ioctl.h
index 5cf40e35f881..8fe1aca9ef12 100644
--- a/fs/fuse/kio/pcs/pcs_ioctl.h
+++ b/fs/fuse/kio/pcs/pcs_ioctl.h
@@ -78,6 +78,11 @@ struct pcs_ioc_csconn
 #define PCS_IOC_CS_REOPEN	(PCS_IOC_CS_OPEN|PCS_IOC_CS_CLOSE)
 };
 
+#define PCS_IOC_NOCSUMONREAD	_IOW('V',3,u32)
+# define PCS_IOC_NOCSUMONREAD_DATA	1
+# define PCS_IOC_NOCSUMONREAD_METADATA	2
+#define PCS_IOC_NOWRITEDELAY	_IOW('V',4,u32)
+
 #define PCS_IOC_INIT_KDIRECT	_IOR('V',32, struct pcs_ioc_init_kdirect)
 #define PCS_IOC_CSCONN		_IOR('V',33, struct pcs_ioc_csconn)
 #define PCS_IOC_GETFILEINFO	_IOR('V',34, struct pcs_ioc_fileinfo)
-- 
2.15.1