4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Greg Edwards <gedwards@xxxxxxx>
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@xxxxxx>
Signed-off-by: Greg Edwards <gedwards@xxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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)