From 340e84573878b2b9d63210482af46883366361b9 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 22 Jul 2021 09:53:54 +0200 Subject: [PATCH] block: delay freeing the gendisk blkdev_get_no_open acquires a reference to the block_device through the block device inode and then tries to acquire a device model reference to the gendisk. But at this point the disk migh already be freed (although the race is free). Fix this by only freeing the gendisk from the whole device bdevs ->free_inode callback as well. Fixes: 22ae8ce8b892 ("block: simplify bdev/disk lookup in blkdev_get") Signed-off-by: Christoph Hellwig Reviewed-by: Josef Bacik Reviewed-by: Ming Lei Link: https://lore.kernel.org/r/20210722075402.983367-2-hch@lst.de Signed-off-by: Jens Axboe --- block/genhd.c | 3 +-- fs/block_dev.c | 2 ++ 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/block/genhd.c b/block/genhd.c index af4d2ab..298ee78 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -1079,10 +1079,9 @@ static void disk_release(struct device *dev) disk_release_events(disk); kfree(disk->random); xa_destroy(&disk->part_tbl); - bdput(disk->part0); if (test_bit(GD_QUEUE_REF, &disk->state) && disk->queue) blk_put_queue(disk->queue); - kfree(disk); + bdput(disk->part0); /* frees the disk */ } struct class block_class = { .name = "block", diff --git a/fs/block_dev.c b/fs/block_dev.c index ca8bf18..a38b0f3 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -812,6 +812,8 @@ static void bdev_free_inode(struct inode *inode) free_percpu(bdev->bd_stats); kfree(bdev->bd_meta_info); + if (!bdev_is_partition(bdev)) + kfree(bdev->bd_disk); kmem_cache_free(bdev_cachep, BDEV_I(inode)); } -- 2.7.4