floppy: fix open(O_ACCMODE) for ioctl-only open

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.

Cc: stable@vger.kernel.org # v4.5+
Reported-by: Wim Osterholt <wim@djo.tudelft.nl>
Tested-by: Wim Osterholt <wim@djo.tudelft.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Jiri Kosina 2016-06-16 09:53:58 +02:00 committed by Jens Axboe
parent c1ece76719
commit ff06db1efb

View File

@ -3663,11 +3663,6 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
opened_bdev[drive] = bdev;
if (!(mode & (FMODE_READ|FMODE_WRITE))) {
res = -EINVAL;
goto out;
}
res = -ENXIO;
if (!floppy_track_buffer) {
@ -3711,13 +3706,15 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
if (UFDCS->rawcmd == 1)
UFDCS->rawcmd = 2;
UDRS->last_checked = 0;
clear_bit(FD_OPEN_SHOULD_FAIL_BIT, &UDRS->flags);
check_disk_change(bdev);
if (test_bit(FD_DISK_CHANGED_BIT, &UDRS->flags))
goto out;
if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &UDRS->flags))
goto out;
if (mode & (FMODE_READ|FMODE_WRITE)) {
UDRS->last_checked = 0;
clear_bit(FD_OPEN_SHOULD_FAIL_BIT, &UDRS->flags);
check_disk_change(bdev);
if (test_bit(FD_DISK_CHANGED_BIT, &UDRS->flags))
goto out;
if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &UDRS->flags))
goto out;
}
res = -EROFS;