From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joseph Qi Date: Wed, 28 Mar 2018 17:50:19 +0800 Subject: [Ocfs2-devel] [PATCH] ocfs2/o2hb: check len for bio_add_page() to avoid submitting incorrect bio In-Reply-To: <5ABB3DEC.5020507@huawei.com> References: <5ABB110A.3050808@huawei.com> <9c5f2dca-dc05-c36d-c6ec-24171fe0a94f@gmail.com> <5ABB3DEC.5020507@huawei.com> Message-ID: <398b95fa-4ed6-bccf-e8f3-b2e118808ea6@gmail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com On 18/3/28 15:02, piaojun wrote: > Hi Joseph, > > On 2018/3/28 12:58, Joseph Qi wrote: >> >> >> On 18/3/28 11:50, piaojun wrote: >>> We need check len for bio_add_page() to make sure the bio has been set up >>> correctly, otherwise we may submit incorrect data to device. >>> >>> Signed-off-by: Jun Piao >>> Reviewed-by: Yiwen Jiang >>> --- >>> fs/ocfs2/cluster/heartbeat.c | 11 ++++++++++- >>> 1 file changed, 10 insertions(+), 1 deletion(-) >>> >>> diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c >>> index ea8c551..43ad79f 100644 >>> --- a/fs/ocfs2/cluster/heartbeat.c >>> +++ b/fs/ocfs2/cluster/heartbeat.c >>> @@ -570,7 +570,16 @@ static struct bio *o2hb_setup_one_bio(struct o2hb_region *reg, >>> current_page, vec_len, vec_start); >>> >>> len = bio_add_page(bio, page, vec_len, vec_start); >>> - if (len != vec_len) break; >>> + if (len != vec_len) { >>> + mlog(ML_ERROR, "Adding page[%d] to bio failed, " >>> + "page %p, len %d, vec_len %u, vec_start %u, " >>> + "bi_sector %llu\n", current_page, page, len, >>> + vec_len, vec_start, >>> + (unsigned long long)bio->bi_iter.bi_sector); >>> + bio_put(bio); >>> + bio = ERR_PTR(-EFAULT); >> >> IMO, EFAULT is not an appropriate error code here. >> If __bio_add_page returns 0, some are caused by bio checking failed. >> Also I've noticed that several other callers just use ENOMEM, so I think >> EINVAL or ENOMEM may be better. > > __bio_add_page has been deleted in patch c66a14d07c13, and I notice that > other callers always use -EFAULT or -EIO. I'm afraid we are not basing on > the same kernel source. > Oops... Yes, I was looking an old kernel... EIO sounds reasonable, but I don't know why EFAULT since it means "Bad address". Thanks, Joseph