Commit 4e325d0a authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Yu Kuai
Browse files

block: propagate partition scanning errors to the BLKRRPART ioctl 

mainline inclusion
from mainline-v6.9-rc5
commit 752863bddacab6b5c5164b1df8c8b2e3a175ee28
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IAFS7F
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=752863bddacab6b5c5164b1df8c8b2e3a175ee28



--------------------------------

Commit 4601b4b1 ("block: reopen the device in blkdev_reread_part")
lost the propagation of I/O errors from the low-level read of the
partition table to the user space caller of the BLKRRPART.

Apparently some user space relies on, so restore the propagation.  This
isn't exactly pretty as other block device open calls explicitly do not
are about these errors, so add a new BLK_OPEN_STRICT_SCAN to opt into
the error propagation.

Fixes: 4601b4b1 ("block: reopen the device in blkdev_reread_part")
Reported-by: default avatarSaranya Muruganandam <saranyamohan@google.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarChaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: default avatarShin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Tested-by: default avatarShin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Link: https://lore.kernel.org/r/20240417144743.2277601-1-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
Signed-off-by: default avatarYu Kuai <yukuai3@huawei.com>
parent 06bfbb03

block/bdev.c

+19 −10
Original line number Diff line number Diff line
@@ -648,6 +648,14 @@ static void blkdev_flush_mapping(struct block_device *bdev) 
	bdev_write_inode(bdev);

}



static void blkdev_put_whole(struct block_device *bdev)

{

	if (atomic_dec_and_test(&bdev->bd_openers))

		blkdev_flush_mapping(bdev);

	if (bdev->bd_disk->fops->release)

		bdev->bd_disk->fops->release(bdev->bd_disk);

}



static int blkdev_get_whole(struct block_device *bdev, blk_mode_t mode)

{

	struct gendisk *disk = bdev->bd_disk;
@@ -666,18 +674,19 @@ static int blkdev_get_whole(struct block_device *bdev, blk_mode_t mode) 


	if (!atomic_read(&bdev->bd_openers))

		set_init_blocksize(bdev);

	if (test_bit(GD_NEED_PART_SCAN, &disk->state))

		bdev_disk_changed(disk, false);

	atomic_inc(&bdev->bd_openers);

	return 0;

	if (test_bit(GD_NEED_PART_SCAN, &disk->state)) {

		/*

		 * Only return scanning errors if we are called from contexts

		 * that explicitly want them, e.g. the BLKRRPART ioctl.

		 */

		ret = bdev_disk_changed(disk, false);

		if (ret && (mode & BLK_OPEN_STRICT_SCAN)) {

			blkdev_put_whole(bdev);

			return ret;

		}



static void blkdev_put_whole(struct block_device *bdev)

{

	if (atomic_dec_and_test(&bdev->bd_openers))

		blkdev_flush_mapping(bdev);

	if (bdev->bd_disk->fops->release)

		bdev->bd_disk->fops->release(bdev->bd_disk);

	}

	return 0;

}



static int blkdev_get_part(struct block_device *part, blk_mode_t mode)

block/ioctl.c

+2 −1
Original line number Diff line number Diff line
@@ -556,7 +556,8 @@ static int blkdev_common_ioctl(struct block_device *bdev, blk_mode_t mode, 
			return -EACCES;

		if (bdev_is_partition(bdev))

			return -EINVAL;

		return disk_scan_partitions(bdev->bd_disk, mode);

		return disk_scan_partitions(bdev->bd_disk,

				mode | BLK_OPEN_STRICT_SCAN);

	case BLKTRACESTART:

	case BLKTRACESTOP:

	case BLKTRACETEARDOWN:

include/linux/blkdev.h

+2 −0
Original line number Diff line number Diff line
@@ -129,6 +129,8 @@ typedef unsigned int __bitwise blk_mode_t; 
#define BLK_OPEN_WRITE_IOCTL	((__force blk_mode_t)(1 << 4))

/* open is exclusive wrt all other BLK_OPEN_WRITE opens to the device */

#define BLK_OPEN_RESTRICT_WRITES	((__force blk_mode_t)(1 << 5))

/* return partition scanning errors */

#define BLK_OPEN_STRICT_SCAN	((__force blk_mode_t)(1 << 6))



struct gendisk {

	/*