Re: [PATCH] always check write protect

[Christoph Hellwig <hch@infradead.org>]

On Tue, Jun 24, 2003 at 09:04:48PM -0000, pc-linscsi2@crowcastle.net wrote:
> The current version of sd.c only checks the write protect status for
> removable media.  This is wrong--you can have write-protected non-removable
> media.  This is common with high-end storage arrays.  This patch corrects
> the behaviour.  It applies with slight line offsets to recent 2.4 kernels,
> including 2.4.21.

What about a patch like the following for 2.5?  It also address your
fixme by calling check_disk_change (and thus sd_revalidate_disk) in
->open when the write_prot flag is set.


diff -Nru a/drivers/scsi/sd.c b/drivers/scsi/sd.c
--- a/drivers/scsi/sd.c	Wed Jun 25 11:47:26 2003
+++ b/drivers/scsi/sd.c	Wed Jun 25 11:47:26 2003
@@ -368,25 +368,24 @@
 	if (!scsi_block_when_processing_errors(sdev))
 		goto error_out;
 
-	if (sdev->removable) {
+	if (sdev->removable || sdkp->write_prot)
 		check_disk_change(inode->i_bdev);
 
-		/*
-		 * If the drive is empty, just let the open fail.
-		 */
-		retval = -ENOMEDIUM;
-		if ((!sdkp->media_present) && !(filp->f_flags & O_NDELAY))
-			goto error_out;
+	/*
+	 * If the drive is empty, just let the open fail.
+	 */
+	retval = -ENOMEDIUM;
+	if (sdev->removable && !sdkp->media_present &&
+	    !(filp->f_flags & O_NDELAY))
+		goto error_out;
 
-		/*
-		 * Similarly, if the device has the write protect tab set,
-		 * have the open fail if the user expects to be able to write
-		 * to the thing.
-		 */
-		retval = -EROFS;
-		if ((sdkp->write_prot) && (filp->f_mode & FMODE_WRITE))
-			goto error_out;
-	}
+	/*
+	 * If the device has the write protect tab set, have the open fail
+	 * if the user expects to be able to write to the thing.
+	 */
+	retval = -EROFS;
+	if ((sdkp->write_prot) && (filp->f_mode & FMODE_WRITE))
+		goto error_out;
 
 	/*
 	 * It is possible that the disk changing stuff resulted in