From f7e3f852a42d7cd8f1af2c330d9d153e30c8adcf Mon Sep 17 00:00:00 2001 From: Shaurya Rane Date: Thu, 4 Dec 2025 23:42:59 +0530 Subject: [PATCH] block: fix memory leak in __blkdev_issue_zero_pages Move the fatal signal check before bio_alloc() to prevent a memory leak when BLKDEV_ZERO_KILLABLE is set and a fatal signal is pending. Previously, the bio was allocated before checking for a fatal signal. If a signal was pending, the code would break out of the loop without freeing or chaining the just-allocated bio, causing a memory leak. This matches the pattern already used in __blkdev_issue_write_zeroes() where the signal check precedes the allocation. Fixes: bf86bcdb4012 ("blk-lib: check for kill signal in ioctl BLKZEROOUT") Reported-by: syzbot+527a7e48a3d3d315d862@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=527a7e48a3d3d315d862 Signed-off-by: Shaurya Rane Reviewed-by: Keith Busch Tested-by: syzbot+527a7e48a3d3d315d862@syzkaller.appspotmail.com Signed-off-by: Jens Axboe --- block/blk-lib.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/block/blk-lib.c b/block/blk-lib.c index 19e0203cc18a9..9e2cc58f881f8 100644 --- a/block/blk-lib.c +++ b/block/blk-lib.c @@ -202,13 +202,13 @@ static void __blkdev_issue_zero_pages(struct block_device *bdev, unsigned int nr_vecs = __blkdev_sectors_to_bio_pages(nr_sects); struct bio *bio; - bio = bio_alloc(bdev, nr_vecs, REQ_OP_WRITE, gfp_mask); - bio->bi_iter.bi_sector = sector; - if ((flags & BLKDEV_ZERO_KILLABLE) && fatal_signal_pending(current)) break; + bio = bio_alloc(bdev, nr_vecs, REQ_OP_WRITE, gfp_mask); + bio->bi_iter.bi_sector = sector; + do { unsigned int len; -- 2.47.3