[patch 5/12] s390: cmm guest sender id.
From: Martin Schwidefsky <[email protected]>
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 <[email protected]>
diffstat:
arch/s390/mm/cmm.c | 9 ++++++++-
drivers/s390/net/smsgiucv.c | 19 ++++++++++++++-----
drivers/s390/net/smsgiucv.h | 4 ++--
3 files changed, 24 insertions(+), 8 deletions(-)
diff -urpN linux-2.6/arch/s390/mm/cmm.c linux-2.6-patched/arch/s390/mm/cmm.c
--- linux-2.6/arch/s390/mm/cmm.c 2005-03-02 08:38:13.000000000 +0100
+++ linux-2.6-patched/arch/s390/mm/cmm.c 2005-04-22 15:45:02.000000000 +0200
@@ -20,6 +20,11 @@
#include <asm/pgalloc.h>
#include <asm/uaccess.h>
+static char *sender = "VMRMSVM";
+module_param(sender, charp, 0);
+MODULE_PARM_DESC(sender,
+ "Guest name that may send SMSG messages (default VMRMSVM)");
+
#include "../../../drivers/s390/net/smsgiucv.h"
#define CMM_NR_PAGES ((PAGE_SIZE / sizeof(unsigned long)) - 2)
@@ -367,10 +372,12 @@ static struct ctl_table cmm_dir_table[]
#ifdef CONFIG_CMM_IUCV
#define SMSG_PREFIX "CMM"
static void
-cmm_smsg_target(char *msg)
+cmm_smsg_target(char *from, char *msg)
{
long pages, seconds;
+ if (strlen(sender) > 0 && strcmp(from, sender) != 0)
+ return;
if (!cmm_skip_blanks(msg + strlen(SMSG_PREFIX), &msg))
return;
if (strncmp(msg, "SHRINK", 6) == 0) {
diff -urpN linux-2.6/drivers/s390/net/smsgiucv.c linux-2.6-patched/drivers/s390/net/smsgiucv.c
--- linux-2.6/drivers/s390/net/smsgiucv.c 2005-03-02 08:37:49.000000000 +0100
+++ linux-2.6-patched/drivers/s390/net/smsgiucv.c 2005-04-22 15:45:02.000000000 +0200
@@ -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
{
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
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, voi
}
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 -urpN linux-2.6/drivers/s390/net/smsgiucv.h linux-2.6-patched/drivers/s390/net/smsgiucv.h
--- linux-2.6/drivers/s390/net/smsgiucv.h 2005-03-02 08:37:49.000000000 +0100
+++ linux-2.6-patched/drivers/s390/net/smsgiucv.h 2005-04-22 15:45:02.000000000 +0200
@@ -5,6 +5,6 @@
* Author(s): Martin Schwidefsky ([email protected])
*/
-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 *));