Commit 15439d74 authored by Martin Schwidefsky's avatar Martin Schwidefsky Committed by Linus Torvalds

[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: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 0b642ede
...@@ -20,6 +20,11 @@ ...@@ -20,6 +20,11 @@
#include <asm/pgalloc.h> #include <asm/pgalloc.h>
#include <asm/uaccess.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" #include "../../../drivers/s390/net/smsgiucv.h"
#define CMM_NR_PAGES ((PAGE_SIZE / sizeof(unsigned long)) - 2) #define CMM_NR_PAGES ((PAGE_SIZE / sizeof(unsigned long)) - 2)
...@@ -367,10 +372,12 @@ static struct ctl_table cmm_dir_table[] = { ...@@ -367,10 +372,12 @@ static struct ctl_table cmm_dir_table[] = {
#ifdef CONFIG_CMM_IUCV #ifdef CONFIG_CMM_IUCV
#define SMSG_PREFIX "CMM" #define SMSG_PREFIX "CMM"
static void static void
cmm_smsg_target(char *msg) cmm_smsg_target(char *from, char *msg)
{ {
long pages, seconds; long pages, seconds;
if (strlen(sender) > 0 && strcmp(from, sender) != 0)
return;
if (!cmm_skip_blanks(msg + strlen(SMSG_PREFIX), &msg)) if (!cmm_skip_blanks(msg + strlen(SMSG_PREFIX), &msg))
return; return;
if (strncmp(msg, "SHRINK", 6) == 0) { if (strncmp(msg, "SHRINK", 6) == 0) {
......
...@@ -32,7 +32,7 @@ struct smsg_callback { ...@@ -32,7 +32,7 @@ struct smsg_callback {
struct list_head list; struct list_head list;
char *prefix; char *prefix;
int len; int len;
void (*callback)(char *str); void (*callback)(char *from, char *str);
}; };
MODULE_AUTHOR MODULE_AUTHOR
...@@ -55,8 +55,9 @@ smsg_message_pending(iucv_MessagePending *eib, void *pgm_data) ...@@ -55,8 +55,9 @@ smsg_message_pending(iucv_MessagePending *eib, void *pgm_data)
{ {
struct smsg_callback *cb; struct smsg_callback *cb;
unsigned char *msg; unsigned char *msg;
unsigned char sender[9];
unsigned short len; unsigned short len;
int rc; int rc, i;
len = eib->ln1msg2.ipbfln1f; len = eib->ln1msg2.ipbfln1f;
msg = kmalloc(len + 1, GFP_ATOMIC|GFP_DMA); msg = kmalloc(len + 1, GFP_ATOMIC|GFP_DMA);
...@@ -69,10 +70,18 @@ smsg_message_pending(iucv_MessagePending *eib, void *pgm_data) ...@@ -69,10 +70,18 @@ smsg_message_pending(iucv_MessagePending *eib, void *pgm_data)
if (rc == 0) { if (rc == 0) {
msg[len] = 0; msg[len] = 0;
EBCASC(msg, len); 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); spin_lock(&smsg_list_lock);
list_for_each_entry(cb, &smsg_list, list) list_for_each_entry(cb, &smsg_list, list)
if (strncmp(msg + 8, cb->prefix, cb->len) == 0) { if (strncmp(msg + 8, cb->prefix, cb->len) == 0) {
cb->callback(msg + 8); cb->callback(sender, msg + 8);
break; break;
} }
spin_unlock(&smsg_list_lock); spin_unlock(&smsg_list_lock);
...@@ -91,7 +100,7 @@ static struct device_driver smsg_driver = { ...@@ -91,7 +100,7 @@ static struct device_driver smsg_driver = {
}; };
int 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; struct smsg_callback *cb;
...@@ -108,7 +117,7 @@ smsg_register_callback(char *prefix, void (*callback)(char *str)) ...@@ -108,7 +117,7 @@ smsg_register_callback(char *prefix, void (*callback)(char *str))
} }
void 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; struct smsg_callback *cb, *tmp;
......
...@@ -5,6 +5,6 @@ ...@@ -5,6 +5,6 @@
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
*/ */
int smsg_register_callback(char *, void (*)(char *)); int smsg_register_callback(char *, void (*)(char *, char *));
void smsg_unregister_callback(char *, void (*)(char *)); void smsg_unregister_callback(char *, void (*)(char *, char *));
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