diff mbox

[v2] fs: guard_bio_eod() needs to consider partitions

Message ID 20171024172148.12397-1-gedwards@ddn.com (mailing list archive)
State New, archived
Headers show

Commit Message

Greg Edwards Oct. 24, 2017, 5:21 p.m. UTC
guard_bio_eod() needs to look at the partition capacity, not just the
capacity of the whole device, when determining if truncation is
necessary.

[   60.268688] attempt to access beyond end of device
[   60.268690] unknown-block(9,1): rw=0, want=67103509, limit=67103506
[   60.268693] buffer_io_error: 2 callbacks suppressed
[   60.268696] Buffer I/O error on dev md1p7, logical block 4524305, async page read

Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index")
Signed-off-by: Greg Edwards <gedwards@ddn.com>
---
Changes from v1:
  * use __disk_get_part instead of disk_get_part, similar to what
    blk_partition_remap does

 fs/buffer.c           | 10 +++++++++-
 include/linux/genhd.h |  1 +
 2 files changed, 10 insertions(+), 1 deletion(-)

Comments

Greg Edwards Nov. 1, 2017, 5:49 p.m. UTC | #1
On Tue, Oct 24, 2017 at 11:21:48AM -0600, Greg Edwards wrote:
> guard_bio_eod() needs to look at the partition capacity, not just the
> capacity of the whole device, when determining if truncation is
> necessary.
>
> [   60.268688] attempt to access beyond end of device
> [   60.268690] unknown-block(9,1): rw=0, want=67103509, limit=67103506
> [   60.268693] buffer_io_error: 2 callbacks suppressed
> [   60.268696] Buffer I/O error on dev md1p7, logical block 4524305, async page read
>
> Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index")
> Signed-off-by: Greg Edwards <gedwards@ddn.com>
> ---
> Changes from v1:
>   * use __disk_get_part instead of disk_get_part, similar to what
>     blk_partition_remap does

Al, Christoph,

Any thoughts on this version?

It would be nice to get this fixed before 4.14 goes out, as this is a
regression from previous releases.

Greg
Christoph Hellwig Nov. 10, 2017, 8:46 a.m. UTC | #2
This looks good to me:

Reviewed-by: Christoph Hellwig <hch@lst.de>

Jens, can you pick it up through the block tree given that is where
the issue was introduced?
Jens Axboe Nov. 10, 2017, 3:25 p.m. UTC | #3
On 11/10/2017 01:46 AM, Christoph Hellwig wrote:
> This looks good to me:
> 
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> 
> Jens, can you pick it up through the block tree given that is where
> the issue was introduced?

I picked it up, and marked it for 4.13 stable as well.
diff mbox

Patch

diff --git a/fs/buffer.c b/fs/buffer.c
index 170df856bdb9..b96f3b98a6ef 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -3055,8 +3055,16 @@  void guard_bio_eod(int op, struct bio *bio)
 	sector_t maxsector;
 	struct bio_vec *bvec = &bio->bi_io_vec[bio->bi_vcnt - 1];
 	unsigned truncated_bytes;
+	struct hd_struct *part;
+
+	rcu_read_lock();
+	part = __disk_get_part(bio->bi_disk, bio->bi_partno);
+	if (part)
+		maxsector = part_nr_sects_read(part);
+	else
+		maxsector = get_capacity(bio->bi_disk);
+	rcu_read_unlock();
 
-	maxsector = get_capacity(bio->bi_disk);
 	if (!maxsector)
 		return;
 
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index ea652bfcd675..cb8c5fd74b71 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -242,6 +242,7 @@  static inline dev_t part_devt(struct hd_struct *part)
 	return part_to_dev(part)->devt;
 }
 
+extern struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 
 static inline void disk_put_part(struct hd_struct *part)