> -----Original Message----- > From: Ben Hutchings [mailto:ben@xxxxxxxxxxxxxxx] > Sent: Wednesday, July 25, 2012 10:47 AM > To: KY Srinivasan > Cc: gregkh@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > devel@xxxxxxxxxxxxxxxxxxxxxx; virtualization@xxxxxxxxxxxxxx; olaf@xxxxxxxxx; > apw@xxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx > Subject: Re: [PATCH 03/17] Drivers: hv: kvp: Cleanup error handling in KVP > > On Wed, Jul 25, 2012 at 02:10:05PM +0000, KY Srinivasan wrote: > > > > > > > -----Original Message----- > > > From: Ben Hutchings [mailto:ben@xxxxxxxxxxxxxxx] > > > Sent: Tuesday, July 24, 2012 9:11 PM > > > To: KY Srinivasan > > > Cc: gregkh@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > > > devel@xxxxxxxxxxxxxxxxxxxxxx; virtualization@xxxxxxxxxxxxxx; olaf@xxxxxxxxx; > > > apw@xxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx > > > Subject: Re: [PATCH 03/17] Drivers: hv: kvp: Cleanup error handling in KVP > > > > > > On Tue, 2012-07-24 at 09:01 -0700, K. Y. Srinivasan wrote: > > > > In preparation to implementing IP injection, cleanup the way we propagate > > > > and handle errors both in the driver as well as in the user level daemon. > > > > > > > > Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> > > > > Reviewed-by: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx> > > > > --- > > > > drivers/hv/hv_kvp.c | 112 > +++++++++++++++++++++++++++++++++++++- > > > -------- > > > > include/linux/hyperv.h | 17 +++++--- > > > > tools/hv/hv_kvp_daemon.c | 70 +++++++++++++++------------- > > > > 3 files changed, 138 insertions(+), 61 deletions(-) > > > > > > > > diff --git a/drivers/hv/hv_kvp.c b/drivers/hv/hv_kvp.c > > > > index 0012eed..9b7fc4a 100644 > > > > --- a/drivers/hv/hv_kvp.c > > > > +++ b/drivers/hv/hv_kvp.c > > > [...] > > > > @@ -109,27 +154,52 @@ kvp_cn_callback(struct cn_msg *msg, struct > > > netlink_skb_parms *nsp) > > > > { > > > > struct hv_kvp_msg *message; > > > > struct hv_kvp_msg_enumerate *data; > > > > + int error = 0; > > > > > > > > message = (struct hv_kvp_msg *)msg->data; > > > > - switch (message->kvp_hdr.operation) { > > > > + > > > > + /* > > > > + * If we are negotiating the version information > > > > + * with the daemon; handle that first. > > > > + */ > > > > + > > > > + if (in_hand_shake) { > > > > + if (kvp_handle_handshake(message)) > > > > + in_hand_shake = false; > > > > + return; > > > > + } > > > > + > > > > + /* > > > > + * Based on the version of the daemon, we propagate errors from the > > > > + * daemon differently. > > > > + */ > > > > + > > > > + data = &message->body.kvp_enum_data; > > > > + > > > > + switch (dm_reg_value) { > > > > case KVP_OP_REGISTER: > > > > - pr_info("KVP: user-mode registering done.\n"); > > > > - kvp_register(); > > > > - kvp_transaction.active = false; > > > > - hv_kvp_onchannelcallback(kvp_transaction.kvp_context); > > > > + /* > > > > + * Null string is used to pass back error condition. > > > > + */ > > > > + if (!strlen(data->data.key)) > > > > > > Do we know that the key is null-terminated here? Shouldn't we just > > > check whether data->data.key[0] == 0? > > > > Yes, currently we do return null string to indicate error. > [...] > > So the kernel should assume userland input is always valid? Good point! This is the existing code and this patch-set cleans up all the error handling and would not have this problem. K. Y _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
