floppy: use del_timer_sync() in init cleanup

When no floppy is found the module code can be released while a timer
function is pending or about to be executed.

CPU0                                  CPU1
				      floppy_init()
timer_softirq()
   spin_lock_irq(&base->lock);
   detach_timer();
   spin_unlock_irq(&base->lock);
   -> Interrupt
					del_timer();
				        return -ENODEV;
                                      module_cleanup();
   <- EOI
   call_timer_fn();
   OOPS

Use del_timer_sync() to prevent this.

Signed-off-by: Carsten Emde <C.Emde@osadl.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 4 insertions, 4 deletions

diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index 98de8f418676..9955a53733b2 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -4250,7 +4250,7 @@ static int __init floppy_init(void)
         use_virtual_dma = can_use_virtual_dma & 1;
         fdc_state[0].address = FDC1;
         if (fdc_state[0].address == -1) {
-                del_timer(&fd_timeout);
+                del_timer_sync(&fd_timeout);
                 err = -ENODEV;
                 goto out_unreg_region;
         }
@@ -4261,7 +4261,7 @@ static int __init floppy_init(void)
         fdc = 0;                /* reset fdc in case of unexpected interrupt */
         err = floppy_grab_irq_and_dma();
         if (err) {
-                del_timer(&fd_timeout);
+                del_timer_sync(&fd_timeout);
                 err = -EBUSY;
                 goto out_unreg_region;
         }
@@ -4318,7 +4318,7 @@ static int __init floppy_init(void)
                 user_reset_fdc(-1, FD_RESET_ALWAYS, false);
         }
         fdc = 0;
-        del_timer(&fd_timeout);
+        del_timer_sync(&fd_timeout);
         current_drive = 0;
         initialized = true;
         if (have_no_fdc) {
@@ -4368,7 +4368,7 @@ out_unreg_blkdev:
         unregister_blkdev(FLOPPY_MAJOR, "fd");
 out_put_disk:
         while (dr--) {
-                del_timer(&motor_off_timer[dr]);
+                del_timer_sync(&motor_off_timer[dr]);
                 if (disks[dr]->queue)
                         blk_cleanup_queue(disks[dr]->queue);
                 put_disk(disks[dr]);