md/raid10: fix memory leak when reshaping a RAID10.

raid10 reshape clears unwanted bits from a bio->bi_flags using
a method which, while clumsy, worked until 3.10 when BIO_OWNS_VEC
was added.
Since then it clears that bit but shouldn't.  This results in a
memory leak.

So change to used the approved method of clearing unwanted bits.

As this causes a memory leak which can consume all of memory
the fix is suitable for -stable.

Fixes: a38352e0ac
Cc: stable@vger.kernel.org (v3.10+)
Reported-by: mdraid.pkoch@dfgh.net (Peter Koch)
Signed-off-by: NeilBrown <neilb@suse.de>
This commit is contained in:
NeilBrown 2014-08-18 13:56:38 +10:00
parent 9c4bdf697c
commit ce0b0a4695

View File

@ -4410,7 +4410,7 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr,
read_bio->bi_private = r10_bio;
read_bio->bi_end_io = end_sync_read;
read_bio->bi_rw = READ;
read_bio->bi_flags &= ~(BIO_POOL_MASK - 1);
read_bio->bi_flags &= (~0UL << BIO_RESET_BITS);
read_bio->bi_flags |= 1 << BIO_UPTODATE;
read_bio->bi_vcnt = 0;
read_bio->bi_iter.bi_size = 0;