1 files changed, 4 insertions, 1 deletions

diff --git a/block/blk-lib.c b/block/blk-lib.c
index 78e627e2581d..2b461b496a78 100644
--- a/block/blk-lib.c
+++ b/block/blk-lib.c
@@ -59,7 +59,10 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
          * granularity
          */
         max_discard_sectors = min(q->limits.max_discard_sectors, UINT_MAX >> 9);
-        if (q->limits.discard_granularity) {
+        if (unlikely(!max_discard_sectors)) {
+                /* Avoid infinite loop below. Being cautious never hurts. */
+                return -EOPNOTSUPP;
+        } else if (q->limits.discard_granularity) {
                 unsigned int disc_sects = q->limits.discard_granularity >> 9;
 
                 max_discard_sectors &= ~(disc_sects - 1);