Skip to contentSkip to conversation

FAILED: patch "[PATCH] floppy: reintroduce O_NDELAY fix" failed to apply to 4.14-stable tree

PATCH [email protected] 1 participant 1 message Mar 1, 2021

Subsystems (3)
lore
Share & tools
lore

[email protected]

author maintainer
#0 lore raw

The patch below does not apply to the 4.14-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 8a0c014cd20516ade9654fc13b51345ec58e7be8 Mon Sep 17 00:00:00 2001
From: Jiri Kosina <[email protected]>
Date: Fri, 22 Jan 2021 12:13:20 +0100
Subject: [PATCH] floppy: reintroduce O_NDELAY fix

This issue was originally fixed in 09954bad4 ("floppy: refactor open() flags handling").

The fix as a side-effect, however, introduce issue for open(O_ACCMODE) that is being used for ioctl-only open. I wrote a fix for that, but instead of it being merged, full revert of 09954bad4 was performed, re-introducing the O_NDELAY / O_NONBLOCK issue, and it strikes again.

This is a forward-port of the original fix to current codebase; the original submission had the changelog below:

====
Commit 09954bad4 ("floppy: refactor open() flags handling"), as a side-effect, causes open(/dev/fdX, O_ACCMODE) to fail. It turns out that this is being used setfdprm userspace for ioctl-only open().

Reintroduce back the original behavior wrt !(FMODE_READ|FMODE_WRITE) modes, while still keeping the original O_NDELAY bug fixed.

Reported-and-tested-by Kurt Garloff <[email protected]>
Fixes 09954bad4 ("floppy: refactor open() flags handling")
Fixes f2791e7ead ("Revert "floppy: refactor open() flags handling"")
drivers/block/floppy.c +15 -15
index dfe1dfc901cc..0b71292d9d5a 100644
@@ -4121,23 +4121,23 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 	if (fdc_state[FDC(drive)].rawcmd == 1)
 		fdc_state[FDC(drive)].rawcmd = 2;
 
-	if (!(mode & FMODE_NDELAY)) {
-		if (mode & (FMODE_READ|FMODE_WRITE)) {
-			drive_state[drive].last_checked = 0;
-			clear_bit(FD_OPEN_SHOULD_FAIL_BIT,
-				  &drive_state[drive].flags);
-			if (bdev_check_media_change(bdev))
-				floppy_revalidate(bdev->bd_disk);
-			if (test_bit(FD_DISK_CHANGED_BIT, &drive_state[drive].flags))
-				goto out;
-			if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &drive_state[drive].flags))
-				goto out;
-		}
-		res = -EROFS;
-		if ((mode & FMODE_WRITE) &&
-		    !test_bit(FD_DISK_WRITABLE_BIT, &drive_state[drive].flags))
+	if (mode & (FMODE_READ|FMODE_WRITE)) {
+		drive_state[drive].last_checked = 0;
+		clear_bit(FD_OPEN_SHOULD_FAIL_BIT, &drive_state[drive].flags);
+		if (bdev_check_media_change(bdev))
+			floppy_revalidate(bdev->bd_disk);
+		if (test_bit(FD_DISK_CHANGED_BIT, &drive_state[drive].flags))
+			goto out;
+		if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &drive_state[drive].flags))
 			goto out;
 	}
+
+	res = -EROFS;
+
+	if ((mode & FMODE_WRITE) &&
+			!test_bit(FD_DISK_WRITABLE_BIT, &drive_state[drive].flags))
+		goto out;
+
 	mutex_unlock(&open_lock);
 	mutex_unlock(&floppy_mutex);
 	return 0;