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This doesn't really make any sense as we never want to send I/O to a device that's been set to zero size, or never moved out of that. I am a bit surprised we haven't caught this for a long time, but the removal of the extra validation inside of zram caused syzbot to trip over this issue recently. I've added a Fixes tag for that commit, but the issue really goes back way before git history. Signed-off-by: Kevin Paul Reddy Janagari --- block/blk-core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/blk-core.c b/block/blk-core.c index 94941e3ce219..6a66f4f6912f 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -515,7 +515,7 @@ static inline int bio_check_eod(struct bio *bio) sector_t maxsector =3D bdev_nr_sectors(bio->bi_bdev); unsigned int nr_sectors =3D bio_sectors(bio); =20 - if (nr_sectors && maxsector && + if (nr_sectors && (nr_sectors > maxsector || bio->bi_iter.bi_sector > maxsector - nr_sectors)) { pr_info_ratelimited("%s: attempt to access beyond end of device\n" --=20 2.39.5