From b777f4c47781df6b23e3f4df6fdb92d9aceac7bb Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Wed, 21 Apr 2021 13:19:45 +0300 Subject: ataflop: fix off by one in ataflop_probe() 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 Signed-off-by: Dan Carpenter Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- drivers/block/ataflop.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'drivers/block') 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]) { -- cgit v1.2.3