diff mbox series

[5.12,435/677] ataflop: fix off by one in ataflop_probe()

Message ID 20210512144851.790467242@linuxfoundation.org
State Superseded
Headers show
Series None | expand

Commit Message

Greg Kroah-Hartman May 12, 2021, 2:48 p.m. UTC 
From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit b777f4c47781df6b23e3f4df6fdb92d9aceac7bb ]

Smatch complains that the "type > NUM_DISK_MINORS" should be >=
instead of >.  We also need to subtract one from "type" at the start.

Fixes: bf9c0538e485 ("ataflop: use a separate gendisk for each media format")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/block/ataflop.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index aed2c2a4f4ea..d601e49f80e0 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c
@@ -2001,7 +2001,10 @@  static void ataflop_probe(dev_t dev)
 	int drive = MINOR(dev) & 3;
 	int type  = MINOR(dev) >> 2;
 
-	if (drive >= FD_MAX_UNITS || type > NUM_DISK_MINORS)
+	if (type)
+		type--;
+
+	if (drive >= FD_MAX_UNITS || type >= NUM_DISK_MINORS)
 		return;
 	mutex_lock(&ataflop_probe_lock);
 	if (!unit[drive].disk[type]) {