diff mbox series

[2/2] ataflop: fix off by one in ataflop_probe()

Message ID YH/8QdfDxhjGjXHG@mwanda (mailing list archive)
State New
Headers show
Series [1/2] ataflop: potential out of bounds in do_format() | expand

Commit Message

Dan Carpenter April 21, 2021, 10:19 a.m. UTC
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>
---
 drivers/block/ataflop.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Comments

Christoph Hellwig April 21, 2021, 2:23 p.m. UTC | #1
On Wed, Apr 21, 2021 at 01:19:45PM +0300, Dan Carpenter wrote:
> 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>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>
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]) {