[PATCH] s390: cmm guest sender id

An arbitrary guest must not be allowed to trigger cmm actions.  Only one
specific guest namely the one that serves as the resource monitor may send cmm
messages.  Add a parameter that allows to specify the guest that may send
messages.  z/VMs resource manager has the name 'VMRMSVM' which is the default.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 16 insertions, 7 deletions

diff --git a/drivers/s390/net/smsgiucv.c b/drivers/s390/net/smsgiucv.c
index a3d2858..1e3f7f3 100644
--- a/drivers/s390/net/smsgiucv.c
+++ b/drivers/s390/net/smsgiucv.c
@@ -32,7 +32,7 @@ struct smsg_callback {
 	struct list_head list;
 	char *prefix;
 	int len;
-	void (*callback)(char *str);
+	void (*callback)(char *from, char *str);
 };
 
 MODULE_AUTHOR
@@ -55,8 +55,9 @@ smsg_message_pending(iucv_MessagePending *eib, void *pgm_data)
 {
 	struct smsg_callback *cb;
 	unsigned char *msg;
+	unsigned char sender[9];
 	unsigned short len;
-	int rc;
+	int rc, i;
 
 	len = eib->ln1msg2.ipbfln1f;
 	msg = kmalloc(len + 1, GFP_ATOMIC|GFP_DMA);
@@ -69,10 +70,18 @@ smsg_message_pending(iucv_MessagePending *eib, void *pgm_data)
 	if (rc == 0) {
 		msg[len] = 0;
 		EBCASC(msg, len);
+		memcpy(sender, msg, 8);
+		sender[8] = 0;
+		/* Remove trailing whitespace from the sender name. */
+		for (i = 7; i >= 0; i--) {
+			if (sender[i] != ' ' && sender[i] != '\t')
+				break;
+			sender[i] = 0;
+		}
 		spin_lock(&smsg_list_lock);
 		list_for_each_entry(cb, &smsg_list, list)
 			if (strncmp(msg + 8, cb->prefix, cb->len) == 0) {
-				cb->callback(msg + 8);
+				cb->callback(sender, msg + 8);
 				break;
 			}
 		spin_unlock(&smsg_list_lock);
@@ -91,7 +100,7 @@ static struct device_driver smsg_driver = {
 };
 
 int
-smsg_register_callback(char *prefix, void (*callback)(char *str))
+smsg_register_callback(char *prefix, void (*callback)(char *from, char *str))
 {
 	struct smsg_callback *cb;
 
@@ -108,7 +117,7 @@ smsg_register_callback(char *prefix, void (*callback)(char *str))
 }
 
 void
-smsg_unregister_callback(char *prefix, void (*callback)(char *str))
+smsg_unregister_callback(char *prefix, void (*callback)(char *from, char *str))
 {
 	struct smsg_callback *cb, *tmp;
 
diff --git a/drivers/s390/net/smsgiucv.h b/drivers/s390/net/smsgiucv.h
index 04cd871..67f5d4f 100644
--- a/drivers/s390/net/smsgiucv.h
+++ b/drivers/s390/net/smsgiucv.h
@@ -5,6 +5,6 @@
  * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
  */
 
-int  smsg_register_callback(char *, void (*)(char *));
-void smsg_unregister_callback(char *, void (*)(char *));
+int  smsg_register_callback(char *, void (*)(char *, char *));
+void smsg_unregister_callback(char *, void (*)(char *, char *));