sg: restore command permission for TYPE_SCANNER

sg allowed any command for TYPE_SCANNER. The cmd_filter patchset
doesn't. We can't change sg's permission since it might break the
existing software.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 14 insertions, 8 deletions

diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 9d28b9f74d90..661f9f21650a 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -217,6 +217,18 @@ static int sg_last_dev(void);
 #define SZ_SG_IOVEC sizeof(sg_iovec_t)
 #define SZ_SG_REQ_INFO sizeof(sg_req_info_t)
 
+static int sg_allow_access(struct file *filp, unsigned char *cmd)
+{
+        struct sg_fd *sfp = (struct sg_fd *)filp->private_data;
+        struct request_queue *q = sfp->parentdp->device->request_queue;
+
+        if (sfp->parentdp->device->type == TYPE_SCANNER)
+                return 0;
+
+        return blk_verify_command(&q->cmd_filter,
+                                  cmd, filp->f_mode & FMODE_WRITE);
+}
+
 static int
 sg_open(struct inode *inode, struct file *filp)
 {
@@ -641,7 +653,6 @@ sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
         unsigned char cmnd[MAX_COMMAND_SIZE];
         int timeout;
         unsigned long ul_timeout;
-        struct request_queue *q;
 
         if (count < SZ_SG_IO_HDR)
                 return -EINVAL;
@@ -690,9 +701,7 @@ sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,
                 sg_remove_request(sfp, srp);
                 return -EFAULT;
         }
-        q = sfp->parentdp->device->request_queue;
-        if (read_only && blk_verify_command(&q->cmd_filter, cmnd,
-                                            file->f_mode & FMODE_WRITE)) {
+        if (read_only && sg_allow_access(file, cmnd)) {
                 sg_remove_request(sfp, srp);
                 return -EPERM;
         }
@@ -1061,14 +1070,11 @@ sg_ioctl(struct inode *inode, struct file *filp,
                         return -ENODEV;
                 if (read_only) {
                         unsigned char opcode = WRITE_6;
-                        struct request_queue *q = sdp->device->request_queue;
                         Scsi_Ioctl_Command __user *siocp = p;
 
                         if (copy_from_user(&opcode, siocp->data, 1))
                                 return -EFAULT;
-                        if (blk_verify_command(&q->cmd_filter,
-                                               &opcode,
-                                               filp->f_mode & FMODE_WRITE))
+                        if (sg_allow_access(filp, &opcode))
                                 return -EPERM;
                 }
                 return sg_scsi_ioctl(filp, sdp->device->request_queue, NULL, p);