linux-kernel - [PATCH V4 10/45] btrfs: avoid to access bvec table directly for a cloned bio

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20171218122247.3488-11-ming.lei@redhat.com>
Date:   Mon, 18 Dec 2017 20:22:12 +0800
From:   Ming Lei <ming.lei@...hat.com>
To:     Jens Axboe <axboe@...com>, Christoph Hellwig <hch@...radead.org>,
        Alexander Viro <viro@...iv.linux.org.uk>,
        Kent Overstreet <kent.overstreet@...il.com>
Cc:     Huang Ying <ying.huang@...el.com>, linux-kernel@...r.kernel.org,
        linux-block@...r.kernel.org, linux-fsdevel@...r.kernel.org,
        linux-mm@...ck.org, Theodore Ts'o <tytso@....edu>,
        "Darrick J . Wong" <darrick.wong@...cle.com>,
        Coly Li <colyli@...e.de>, Filipe Manana <fdmanana@...il.com>,
        Ming Lei <ming.lei@...hat.com>, Chris Mason <clm@...com>,
        Josef Bacik <jbacik@...com>, David Sterba <dsterba@...e.com>,
        linux-btrfs@...r.kernel.org, Liu Bo <bo.li.liu@...cle.com>
Subject: [PATCH V4 10/45] btrfs: avoid to access bvec table directly for a cloned bio

Commit 17347cec15f919901c90(Btrfs: change how we iterate bios in endio)
mentioned that for dio the submitted bio may be fast cloned, we
can't access the bvec table directly for a cloned bio, so use
bio_get_first_bvec() to retrieve the 1st bvec.

Cc: Chris Mason <clm@...com>
Cc: Josef Bacik <jbacik@...com>
Cc: David Sterba <dsterba@...e.com>
Cc: linux-btrfs@...r.kernel.org
Cc: Liu Bo <bo.li.liu@...cle.com>
Reviewed-by: Liu Bo <bo.li.liu@...cle.com>
Acked: David Sterba <dsterba@...e.com>
Signed-off-by: Ming Lei <ming.lei@...hat.com>
---
 fs/btrfs/inode.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 4d5cb6e93c80..cb1e2d201434 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -8015,6 +8015,7 @@ static blk_status_t dio_read_error(struct inode *inode, struct bio *failed_bio,
 	int segs;
 	int ret;
 	blk_status_t status;
+	struct bio_vec bvec;
 
 	BUG_ON(bio_op(failed_bio) == REQ_OP_WRITE);
 
@@ -8030,8 +8031,9 @@ static blk_status_t dio_read_error(struct inode *inode, struct bio *failed_bio,
 	}
 
 	segs = bio_segments(failed_bio);
+	bio_get_first_bvec(failed_bio, &bvec);
 	if (segs > 1 ||
-	    (failed_bio->bi_io_vec->bv_len > btrfs_inode_sectorsize(inode)))
+	    (bvec.bv_len > btrfs_inode_sectorsize(inode)))
 		read_mode |= REQ_FAILFAST_DEV;
 
 	isector = start - btrfs_io_bio(failed_bio)->logical;
-- 
2.9.5