Patch "fs: guard_bio_eod() needs to consider partitions" has been added to the 4.14-stable tree

Patch "fs: guard_bio_eod() needs to consider partitions" has been added to the 4.14-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    fs: guard_bio_eod() needs to consider partitions

to the 4.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     fs-guard_bio_eod-needs-to-consider-partitions.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 67f2519fe2903c4041c0e94394d14d372fe51399 Mon Sep 17 00:00:00 2001
From: Greg Edwards <gedwards@ddn.com>
Date: Tue, 24 Oct 2017 11:21:48 -0600
Subject: fs: guard_bio_eod() needs to consider partitions

From: Greg Edwards <gedwards@ddn.com>

commit 67f2519fe2903c4041c0e94394d14d372fe51399 upstream.

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")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Edwards <gedwards@ddn.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -3055,8 +3055,16 @@ void guard_bio_eod(int op, struct bio *b
 	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;
 
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -243,6 +243,7 @@ static inline dev_t part_devt(struct hd_
 	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)


Patches currently in stable-queue which might be from gedwards@ddn.com are

queue-4.14/fs-guard_bio_eod-needs-to-consider-partitions.patch