Message ID | 513B6520.8050303@inktank.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Reviewed-by: Josh Durgin <josh.durgin@inktank.com> On 03/09/2013 08:36 AM, Alex Elder wrote: > This patch is available in the branch "review/wip-msgr-refactor" > (prior to 6 other patches) in the ceph-client git repository. > That branch is based on branch "review/wip-abstract-2". > > -Alex > > At one time it was necessary to clear a message's bio_iter field to > avoid a bad pointer dereference in write_partial_msg_pages(). > > That no longer seems to be the case. Here's why. > > The message's bio fields represent (in this case) outgoing data. > Between where the bio_iter is made NULL in prepare_write_message() > and the call in that function to prepare_message_data(), the > bio fields are never used. > > In prepare_message_data(), init-bio_iter() is called, and the result > of that overwrites the value in the message's bio_iter field. > > Because it gets overwritten anyway, there is no need to set it to > NULL. So don't do it. > > This resolves: > http://tracker.ceph.com/issues/4402 > > Signed-off-by: Alex Elder <elder@inktank.com> > --- > net/ceph/messenger.c | 4 ---- > 1 file changed, 4 deletions(-) > > diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c > index e75a03d..17d9321 100644 > --- a/net/ceph/messenger.c > +++ b/net/ceph/messenger.c > @@ -804,10 +804,6 @@ static void prepare_write_message(struct > ceph_connection *con) > m->hdr.seq = cpu_to_le64(++con->out_seq); > m->needs_out_seq = false; > } > -#ifdef CONFIG_BLOCK > - else > - m->bio_iter = NULL; > -#endif > > dout("prepare_write_message %p seq %lld type %d len %d+%d+%d (%zd)\n", > m, con->out_seq, le16_to_cpu(m->hdr.type), > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c index e75a03d..17d9321 100644 --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -804,10 +804,6 @@ static void prepare_write_message(struct ceph_connection *con) m->hdr.seq = cpu_to_le64(++con->out_seq); m->needs_out_seq = false; } -#ifdef CONFIG_BLOCK - else - m->bio_iter = NULL; -#endif dout("prepare_write_message %p seq %lld type %d len %d+%d+%d (%zd)\n",
This patch is available in the branch "review/wip-msgr-refactor" (prior to 6 other patches) in the ceph-client git repository. That branch is based on branch "review/wip-abstract-2". -Alex At one time it was necessary to clear a message's bio_iter field to avoid a bad pointer dereference in write_partial_msg_pages(). That no longer seems to be the case. Here's why. The message's bio fields represent (in this case) outgoing data. Between where the bio_iter is made NULL in prepare_write_message() and the call in that function to prepare_message_data(), the bio fields are never used. In prepare_message_data(), init-bio_iter() is called, and the result of that overwrites the value in the message's bio_iter field. Because it gets overwritten anyway, there is no need to set it to NULL. So don't do it. This resolves: http://tracker.ceph.com/issues/4402 Signed-off-by: Alex Elder <elder@inktank.com> --- net/ceph/messenger.c | 4 ---- 1 file changed, 4 deletions(-) m, con->out_seq, le16_to_cpu(m->hdr.type),