[PATCH] ipmi: fix panic ipmb response

The "null message handler" in the IPMI driver is used in startup and panic
situations to handle messages.  It was only designed to work with messages
from the local management controller, but in some cases it was used to get
messages from remote managmenet controllers, and the system would then
panic.  This patch makes the "null message handler" in the IPMI driver more
general so it works with any kind of message.
Signed-off-by: Corey Minyard <minyard@acm.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/char/ipmi/ipmi_msghandler.c

@@ -219,7 +219,7 @@ struct ipmi_smi
 	   interface comes in with a NULL user, call this routine with
 	   it.  Note that the message will still be freed by the
 	   caller.  This only works on the system interface. */
-	void (*null_user_handler)(ipmi_smi_t intf, struct ipmi_smi_msg *msg);
+	void (*null_user_handler)(ipmi_smi_t intf, struct ipmi_recv_msg *msg);
 
 	/* When we are scanning the channels for an SMI, this will
 	   tell which channel we are scanning. */
@@ -459,7 +459,27 @@ unsigned int ipmi_addr_length(int addr_type)
 
 static void deliver_response(struct ipmi_recv_msg *msg)
 {
-	msg->user->handler->ipmi_recv_hndl(msg, msg->user->handler_data);
+	if (! msg->user) {
+		ipmi_smi_t    intf = msg->user_msg_data;
+		unsigned long flags;
+
+		/* Special handling for NULL users. */
+		if (intf->null_user_handler) {
+			intf->null_user_handler(intf, msg);
+			spin_lock_irqsave(&intf->counter_lock, flags);
+			intf->handled_local_responses++;
+			spin_unlock_irqrestore(&intf->counter_lock, flags);
+		} else {
+			/* No handler, so give up. */
+			spin_lock_irqsave(&intf->counter_lock, flags);
+			intf->unhandled_local_responses++;
+			spin_unlock_irqrestore(&intf->counter_lock, flags);
+		}
+		ipmi_free_recv_msg(msg);
+	} else {
+		msg->user->handler->ipmi_recv_hndl(msg,
+						   msg->user->handler_data);
+	}
 }
 
 /* Find the next sequence number not being used and add the given
@@ -1389,6 +1409,8 @@ int ipmi_request_settime(ipmi_user_t      user,
 	unsigned char saddr, lun;
 	int           rv;
 
+	if (! user)
+		return -EINVAL;
 	rv = check_addr(user->intf, addr, &saddr, &lun);
 	if (rv)
 		return rv;
@@ -1418,6 +1440,8 @@ int ipmi_request_supply_msgs(ipmi_user_t          user,
 	unsigned char saddr, lun;
 	int           rv;
 
+	if (! user)
+		return -EINVAL;
 	rv = check_addr(user->intf, addr, &saddr, &lun);
 	if (rv)
 		return rv;
@@ -1638,7 +1662,7 @@ send_channel_info_cmd(ipmi_smi_t intf, int chan)
 			      (struct ipmi_addr *) &si,
 			      0,
 			      &msg,
-			      NULL,
+			      intf,
 			      NULL,
 			      NULL,
 			      0,
@@ -1648,19 +1672,20 @@ send_channel_info_cmd(ipmi_smi_t intf, int chan)
 }
 
 static void
-channel_handler(ipmi_smi_t intf, struct ipmi_smi_msg *msg)
+channel_handler(ipmi_smi_t intf, struct ipmi_recv_msg *msg)
 {
 	int rv = 0;
 	int chan;
 
-	if ((msg->rsp[0] == (IPMI_NETFN_APP_RESPONSE << 2))
-	    && (msg->rsp[1] == IPMI_GET_CHANNEL_INFO_CMD))
+	if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
+	    && (msg->msg.netfn == IPMI_NETFN_APP_RESPONSE)
+	    && (msg->msg.cmd == IPMI_GET_CHANNEL_INFO_CMD))
 	{
 		/* It's the one we want */
-		if (msg->rsp[2] != 0) {
+		if (msg->msg.data[0] != 0) {
 			/* Got an error from the channel, just go on. */
 
-			if (msg->rsp[2] == IPMI_INVALID_COMMAND_ERR) {
+			if (msg->msg.data[0] == IPMI_INVALID_COMMAND_ERR) {
 				/* If the MC does not support this
 				   command, that is legal.  We just
 				   assume it has one IPMB at channel
@@ -1677,13 +1702,13 @@ channel_handler(ipmi_smi_t intf, struct ipmi_smi_msg *msg)
 			}
 			goto next_channel;
 		}
-		if (msg->rsp_size < 6) {
+		if (msg->msg.data_len < 4) {
 			/* Message not big enough, just go on. */
 			goto next_channel;
 		}
 		chan = intf->curr_channel;
-		intf->channels[chan].medium = msg->rsp[4] & 0x7f;
-		intf->channels[chan].protocol = msg->rsp[5] & 0x1f;
+		intf->channels[chan].medium = msg->msg.data[2] & 0x7f;
+		intf->channels[chan].protocol = msg->msg.data[3] & 0x1f;
 
 	next_channel:
 		intf->curr_channel++;
@@ -2382,6 +2407,14 @@ static int handle_bmc_rsp(ipmi_smi_t          intf,
 	unsigned long        flags;
 
 	recv_msg = (struct ipmi_recv_msg *) msg->user_data;
+	if (recv_msg == NULL)
+	{
+		printk(KERN_WARNING"IPMI message received with no owner. This\n"
+			"could be because of a malformed message, or\n"
+			"because of a hardware error.  Contact your\n"
+			"hardware vender for assistance\n");
+		return 0;
+	}
 
 	/* Make sure the user still exists. */
 	list_for_each_entry(user, &(intf->users), link) {
@@ -2392,19 +2425,11 @@ static int handle_bmc_rsp(ipmi_smi_t          intf,
 		}
 	}
 
-	if (!found) {
-		/* Special handling for NULL users. */
-		if (!recv_msg->user && intf->null_user_handler){
-			intf->null_user_handler(intf, msg);
-			spin_lock_irqsave(&intf->counter_lock, flags);
-			intf->handled_local_responses++;
-			spin_unlock_irqrestore(&intf->counter_lock, flags);
-		}else{
-			/* The user for the message went away, so give up. */
-			spin_lock_irqsave(&intf->counter_lock, flags);
-			intf->unhandled_local_responses++;
-			spin_unlock_irqrestore(&intf->counter_lock, flags);
-		}
+	if ((! found) && recv_msg->user) {
+		/* The user for the message went away, so give up. */
+		spin_lock_irqsave(&intf->counter_lock, flags);
+		intf->unhandled_local_responses++;
+		spin_unlock_irqrestore(&intf->counter_lock, flags);
 		ipmi_free_recv_msg(recv_msg);
 	} else {
 		struct ipmi_system_interface_addr *smi_addr;
@@ -2890,28 +2915,30 @@ static void dummy_recv_done_handler(struct ipmi_recv_msg *msg)
 }
 
 #ifdef CONFIG_IPMI_PANIC_STRING
-static void event_receiver_fetcher(ipmi_smi_t intf, struct ipmi_smi_msg *msg)
+static void event_receiver_fetcher(ipmi_smi_t intf, struct ipmi_recv_msg *msg)
 {
-	if ((msg->rsp[0] == (IPMI_NETFN_SENSOR_EVENT_RESPONSE << 2))
-	    && (msg->rsp[1] == IPMI_GET_EVENT_RECEIVER_CMD)
-	    && (msg->rsp[2] == IPMI_CC_NO_ERROR))
+	if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
+	    && (msg->msg.netfn == IPMI_NETFN_SENSOR_EVENT_RESPONSE)
+	    && (msg->msg.cmd == IPMI_GET_EVENT_RECEIVER_CMD)
+	    && (msg->msg.data[0] == IPMI_CC_NO_ERROR))
 	{
 		/* A get event receiver command, save it. */
-		intf->event_receiver = msg->rsp[3];
-		intf->event_receiver_lun = msg->rsp[4] & 0x3;
+		intf->event_receiver = msg->msg.data[1];
+		intf->event_receiver_lun = msg->msg.data[2] & 0x3;
 	}
 }
 
-static void device_id_fetcher(ipmi_smi_t intf, struct ipmi_smi_msg *msg)
+static void device_id_fetcher(ipmi_smi_t intf, struct ipmi_recv_msg *msg)
 {
-	if ((msg->rsp[0] == (IPMI_NETFN_APP_RESPONSE << 2))
-	    && (msg->rsp[1] == IPMI_GET_DEVICE_ID_CMD)
-	    && (msg->rsp[2] == IPMI_CC_NO_ERROR))
+	if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
+	    && (msg->msg.netfn == IPMI_NETFN_APP_RESPONSE)
+	    && (msg->msg.cmd == IPMI_GET_DEVICE_ID_CMD)
+	    && (msg->msg.data[0] == IPMI_CC_NO_ERROR))
 	{
 		/* A get device id command, save if we are an event
 		   receiver or generator. */
-		intf->local_sel_device = (msg->rsp[8] >> 2) & 1;
-		intf->local_event_generator = (msg->rsp[8] >> 5) & 1;
+		intf->local_sel_device = (msg->msg.data[6] >> 2) & 1;
+		intf->local_event_generator = (msg->msg.data[6] >> 5) & 1;
 	}
 }
 #endif
@@ -2967,7 +2994,7 @@ static void send_panic_events(char *str)
 			       &addr,
 			       0,
 			       &msg,
-			       NULL,
+			       intf,
 			       &smi_msg,
 			       &recv_msg,
 			       0,
@@ -3013,7 +3040,7 @@ static void send_panic_events(char *str)
 			       &addr,
 			       0,
 			       &msg,
-			       NULL,
+			       intf,
 			       &smi_msg,
 			       &recv_msg,
 			       0,
@@ -3033,7 +3060,7 @@ static void send_panic_events(char *str)
 				       &addr,
 				       0,
 				       &msg,
-				       NULL,
+				       intf,
 				       &smi_msg,
 				       &recv_msg,
 				       0,
@@ -3095,7 +3122,7 @@ static void send_panic_events(char *str)
 				       &addr,
 				       0,
 				       &msg,
-				       NULL,
+				       intf,
 				       &smi_msg,
 				       &recv_msg,
 				       0,

include/linux/ipmi.h

@@ -242,7 +242,8 @@ struct ipmi_recv_msg
 	/* The user_msg_data is the data supplied when a message was
 	   sent, if this is a response to a sent message.  If this is
 	   not a response to a sent message, then user_msg_data will
-	   be NULL. */
+	   be NULL.  If the user above is NULL, then this will be the
+	   intf. */
 	void             *user_msg_data;
 
 	/* Call this when done with the message.  It will presumably free