[PATCH] nvme/ioctl: check SUBMIT_IO with nvme_cmd_allowed()

[Yang Xiuwei]

Unlike IO_CMD / IO64_CMD, NVME_IOCTL_SUBMIT_IO never calls
nvme_cmd_allowed(). Unprivileged callers can thus issue I/O on a
partition device or write through a read-only file descriptor.

Pass flags and open_for_write through and reject disallowed commands
with -EACCES.

Signed-off-by: Yang Xiuwei <yangxiuwei at kylinos.cn>
---
 drivers/nvme/host/ioctl.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c
index 664216eece4a..752d7b249000 100644
--- a/drivers/nvme/host/ioctl.c
+++ b/drivers/nvme/host/ioctl.c
@@ -202,7 +202,8 @@ static int nvme_submit_user_cmd(struct request_queue *q,
 	return ret;
 }
 
-static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
+static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio,
+		unsigned int flags, bool open_for_write)
 {
 	struct nvme_user_io io;
 	struct nvme_command c;
@@ -260,6 +261,9 @@ static int nvme_submit_io(struct nvme_ns *ns, struct nvme_user_io __user *uio)
 	c.rw.lbat = cpu_to_le16(io.apptag);
 	c.rw.lbatm = cpu_to_le16(io.appmask);
 
+	if (!nvme_cmd_allowed(ns, &c, flags, open_for_write))
+		return -EACCES;
+
 	return nvme_submit_user_cmd(ns->queue, &c, io.addr, length, metadata,
 			meta_len, NULL, 0, 0);
 }
@@ -595,7 +599,7 @@ static int nvme_ns_ioctl(struct nvme_ns *ns, unsigned int cmd,
 	case NVME_IOCTL_SUBMIT_IO32:
 #endif
 	case NVME_IOCTL_SUBMIT_IO:
-		return nvme_submit_io(ns, argp);
+		return nvme_submit_io(ns, argp, flags, open_for_write);
 	case NVME_IOCTL_IO64_CMD_VEC:
 		flags |= NVME_IOCTL_VEC;
 		fallthrough;
-- 
2.25.1