4.7-stable review patch. If anyone has any objections, please let me know.
------------------ From: Jiri Kosina <[email protected]> commit ff06db1efb2ad6db06eb5b99b88a0c15a9cc9b0e upstream. 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-by: Wim Osterholt <[email protected]> Tested-by: Wim Osterholt <[email protected]> Signed-off-by: Jiri Kosina <[email protected]> Signed-off-by: Jens Axboe <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/block/floppy.c | 21 +++++++++------------ 1 file changed, 9 insertions(+), 12 deletions(-) --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -3663,11 +3663,6 @@ static int floppy_open(struct block_devi 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_devi 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;
