Previously, we were opportunistically initializing the bio_iter if it appeared to be uninitialized in the middle of the read path. The problem is that a sequence like:
- start reading message - initialize bio_iter - read half a message - messenger fault, reconnect - restart reading message - ** bio_iter now non-NULL, not reinitialized ** - read past end of bio, crash Instead, initialize the bio_iter unconditionally when we allocate/claim the message for read. Signed-off-by: Sage Weil <[email protected]> --- net/ceph/messenger.c | 11 ++++++----- 1 files changed, 6 insertions(+), 5 deletions(-) diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c index e24310e..efa369f 100644 --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -1876,6 +1876,11 @@ static int read_partial_message(struct ceph_connection *con) else con->in_msg_pos.page_pos = 0; con->in_msg_pos.data_pos = 0; + +#ifdef CONFIG_BLOCK + if (m->bio) + init_bio_iter(m->bio, &m->bio_iter, &m->bio_seg); +#endif } /* front */ @@ -1892,10 +1897,6 @@ static int read_partial_message(struct ceph_connection *con) if (ret <= 0) return ret; } -#ifdef CONFIG_BLOCK - if (m->bio && !m->bio_iter) - init_bio_iter(m->bio, &m->bio_iter, &m->bio_seg); -#endif /* (page) data */ while (con->in_msg_pos.data_pos < data_len) { @@ -1906,7 +1907,7 @@ static int read_partial_message(struct ceph_connection *con) return ret; #ifdef CONFIG_BLOCK } else if (m->bio) { - + BUG_ON(!m->bio_iter); ret = read_partial_message_bio(con, &m->bio_iter, &m->bio_seg, data_len, do_datacrc); -- 1.7.9 -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
