block: check for max_hw_sectors underflow

The logical block size need to be smaller than the max_hw_sector
setting, otherwise we can't even transfer a single LBA.

Signed-off-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-settings.c b/block/blk-settings.c
index 7a672021daee6abf3c0af487df12368ecc2f9222..effeb9a639bb459e36e0ae2e8ab9deeeeedc1103 100644 (file)
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -104,6 +104,7 @@ static int blk_validate_zoned_limits(struct queue_limits *lim)
 static int blk_validate_limits(struct queue_limits *lim)
 {
        unsigned int max_hw_sectors;
+       unsigned int logical_block_sectors;
 
        /*
         * Unless otherwise specified, default to 512 byte logical blocks and a
@@ -134,8 +135,11 @@ static int blk_validate_limits(struct queue_limits *lim)
                lim->max_hw_sectors = BLK_SAFE_MAX_SECTORS;
        if (WARN_ON_ONCE(lim->max_hw_sectors < PAGE_SECTORS))
                return -EINVAL;
+       logical_block_sectors = lim->logical_block_size >> SECTOR_SHIFT;
+       if (WARN_ON_ONCE(logical_block_sectors > lim->max_hw_sectors))
+               return -EINVAL;
        lim->max_hw_sectors = round_down(lim->max_hw_sectors,
-                       lim->logical_block_size >> SECTOR_SHIFT);
+                       logical_block_sectors);
 
        /*
         * The actual max_sectors value is a complex beast and also takes the
@@ -153,7 +157,7 @@ static int blk_validate_limits(struct queue_limits *lim)
                lim->max_sectors = min(max_hw_sectors, BLK_DEF_MAX_SECTORS_CAP);
        }
        lim->max_sectors = round_down(lim->max_sectors,
-                       lim->logical_block_size >> SECTOR_SHIFT);
+                       logical_block_sectors);
 
        /*
         * Random default for the maximum number of segments.  Driver should not