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blk-lib: fix blkdev_issue_secure_erase

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There's a bug in blkdev_issue_secure_erase. The statement
"unsigned int len = min_t(sector_t, nr_sects, max_sectors);"
sets the variable "len" to the length in sectors, but the statement
"bio->bi_iter.bi_size = len" treats it as if it were in bytes.
The statements "sector += len << SECTOR_SHIFT" and "nr_sects -= len <<
SECTOR_SHIFT" are thinko.

This patch fixes it.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org	# v5.19
Fixes: 44abff2c0b ("block: decouple REQ_OP_SECURE_ERASE from REQ_OP_DISCARD")
Link: https://lore.kernel.org/r/alpine.LRH.2.02.2209141549480.28100@file01.intranet.prod.int.rdu2.redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Mikulas Patocka 2022-09-14 16:55:51 -04:00 committed by Jens Axboe
parent 56f99b8d06
commit c4fa368466
1 changed files with 8 additions and 3 deletions
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11
block/blk-lib.c
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@ -309,6 +309,11 @@ int blkdev_issue_secure_erase(struct block_device *bdev, sector_t sector,
struct blk_plug plug;
int ret = 0;
/* make sure that "len << SECTOR_SHIFT" doesn't overflow */
if (max_sectors > UINT_MAX >> SECTOR_SHIFT)
max_sectors = UINT_MAX >> SECTOR_SHIFT;
max_sectors &= ~bs_mask;
if (max_sectors == 0)
return -EOPNOTSUPP;
if ((sector | nr_sects) & bs_mask)
@ -322,10 +327,10 @@ int blkdev_issue_secure_erase(struct block_device *bdev, sector_t sector,
bio = blk_next_bio(bio, bdev, 0, REQ_OP_SECURE_ERASE, gfp);
bio->bi_iter.bi_sector = sector;
bio->bi_iter.bi_size = len;
bio->bi_iter.bi_size = len << SECTOR_SHIFT;
sector += len << SECTOR_SHIFT;
nr_sects -= len << SECTOR_SHIFT;
sector += len;
nr_sects -= len;
if (!nr_sects) {
ret = submit_bio_wait(bio);
bio_put(bio);