From 1de67e8e28fc47d71ee06ffa0185da549b378ffb Mon Sep 17 00:00:00 2001 From: John Garry Date: Fri, 11 Jul 2025 10:52:54 +0000 Subject: [PATCH] block: sanitize chunk_sectors for atomic write limits Currently we just ensure that a non-zero value in chunk_sectors aligns with any atomic write boundary, as the blk boundary functionality uses both these values. However it is also improper to have atomic write unit max > chunk_sectors (for non-zero chunk_sectors), as this would lead to splitting of atomic write bios (which is disallowed). Sanitize atomic write unit max against chunk_sectors to avoid any potential problems. Fixes: d00eea91deaf3 ("block: Add extra checks in blk_validate_atomic_write_limits()") Reviewed-by: Nilay Shroff Signed-off-by: John Garry Reviewed-by: Martin K. Petersen Link: https://lore.kernel.org/r/20250711105258.3135198-3-john.g.garry@oracle.com Signed-off-by: Jens Axboe --- block/blk-settings.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/block/blk-settings.c b/block/blk-settings.c index a000daafbfb48..3425ae1b1f014 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -181,6 +181,8 @@ static void blk_atomic_writes_update_limits(struct queue_limits *lim) static void blk_validate_atomic_write_limits(struct queue_limits *lim) { unsigned int boundary_sectors; + unsigned int atomic_write_hw_max_sectors = + lim->atomic_write_hw_max >> SECTOR_SHIFT; if (!(lim->features & BLK_FEAT_ATOMIC_WRITES)) goto unsupported; @@ -202,6 +204,10 @@ static void blk_validate_atomic_write_limits(struct queue_limits *lim) lim->atomic_write_hw_max)) goto unsupported; + if (WARN_ON_ONCE(lim->chunk_sectors && + atomic_write_hw_max_sectors > lim->chunk_sectors)) + goto unsupported; + boundary_sectors = lim->atomic_write_hw_boundary >> SECTOR_SHIFT; if (boundary_sectors) { -- 2.47.2