[PATCH 1/3] block: avoid integer overflows in max_integrity_io_size

[Christoph Hellwig <hch@lst.de>]

Sashiko reports that the calculation in max_integrity_io_size could
overflow a u32 when using 16kiB or larger LBA sizes.  Fix this by
evaluating the maximum size as a 64-bit integer.

Fixes: ec7f31b2a2d3 ("block: make bio auto-integrity deadlock safe")
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/blkdev.h | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 4f7905c3412b..098a65f3e48b 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1816,9 +1816,11 @@ static inline int bio_split_rw_at(struct bio *bio,
  */
 static inline unsigned int max_integrity_io_size(struct queue_limits *lim)
 {
-	return min_t(unsigned int, lim->max_segment_size,
-		(BLK_INTEGRITY_MAX_SIZE / lim->integrity.metadata_size) <<
-			lim->integrity.interval_exp);
+	u64 max_intervals;
+
+	max_intervals = BLK_INTEGRITY_MAX_SIZE / lim->integrity.metadata_size;
+	return min_t(u64, lim->max_segment_size,
+		max_intervals << lim->integrity.interval_exp);
 }
 
 #define DEFINE_IO_COMP_BATCH(name)	struct io_comp_batch name = { }
-- 
2.53.0