s390/qeth: sanitize strings in debug messages

As Documentation/s390/s390dbf.txt states quite clearly, using any
pointer in sprinf-formatted s390dbf debug entries is dangerous.
The pointers are dereferenced whenever the trace file is read from.
So if the referenced data has a shorter life-time than the trace file,
any read operation can result in a use-after-free.

So rip out all hazardous use of indirect data, and replace any usage of
dev_name() and such by the Bus ID number.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 35 insertions, 69 deletions

diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index 0b161cc1fd2e..ffa2aa1dd4c5 100644
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -494,9 +494,8 @@ int qeth_l3_setrouting_v4(struct qeth_card *card)
 				  QETH_PROT_IPV4);
 	if (rc) {
 		card->options.route4.type = NO_ROUTER;
-		QETH_DBF_MESSAGE(2, "Error (0x%04x) while setting routing type"
-			" on %s. Type set to 'no router'.\n", rc,
-			QETH_CARD_IFNAME(card));
+		QETH_DBF_MESSAGE(2, "Error (%#06x) while setting routing type on device %x. Type set to 'no router'.\n",
+				 rc, CARD_DEVID(card));
 	}
 	return rc;
 }
@@ -518,9 +517,8 @@ int qeth_l3_setrouting_v6(struct qeth_card *card)
 				  QETH_PROT_IPV6);
 	if (rc) {
 		card->options.route6.type = NO_ROUTER;
-		QETH_DBF_MESSAGE(2, "Error (0x%04x) while setting routing type"
-			" on %s. Type set to 'no router'.\n", rc,
-			QETH_CARD_IFNAME(card));
+		QETH_DBF_MESSAGE(2, "Error (%#06x) while setting routing type on device %x. Type set to 'no router'.\n",
+				 rc, CARD_DEVID(card));
 	}
 	return rc;
 }
@@ -1070,8 +1068,8 @@ qeth_diags_trace_cb(struct qeth_card *card, struct qeth_reply *reply,
 		}
 		break;
 	default:
-		QETH_DBF_MESSAGE(2, "Unknown sniffer action (0x%04x) on %s\n",
-			cmd->data.diagass.action, QETH_CARD_IFNAME(card));
+		QETH_DBF_MESSAGE(2, "Unknown sniffer action (%#06x) on device %x\n",
+				 cmd->data.diagass.action, CARD_DEVID(card));
 	}
 
 	return 0;
@@ -1517,32 +1515,25 @@ static void qeth_l3_set_rx_mode(struct net_device *dev)
 	qeth_l3_handle_promisc_mode(card);
 }
 
-static const char *qeth_l3_arp_get_error_cause(int *rc)
+static int qeth_l3_arp_makerc(int rc)
 {
-	switch (*rc) {
-	case QETH_IPA_ARP_RC_FAILED:
-		*rc = -EIO;
-		return "operation failed";
+	switch (rc) {
+	case IPA_RC_SUCCESS:
+		return 0;
 	case QETH_IPA_ARP_RC_NOTSUPP:
-		*rc = -EOPNOTSUPP;
-		return "operation not supported";
-	case QETH_IPA_ARP_RC_OUT_OF_RANGE:
-		*rc = -EINVAL;
-		return "argument out of range";
 	case QETH_IPA_ARP_RC_Q_NOTSUPP:
-		*rc = -EOPNOTSUPP;
-		return "query operation not supported";
+		return -EOPNOTSUPP;
+	case QETH_IPA_ARP_RC_OUT_OF_RANGE:
+		return -EINVAL;
 	case QETH_IPA_ARP_RC_Q_NO_DATA:
-		*rc = -ENOENT;
-		return "no query data available";
+		return -ENOENT;
 	default:
-		return "unknown error";
+		return -EIO;
 	}
 }
 
 static int qeth_l3_arp_set_no_entries(struct qeth_card *card, int no_entries)
 {
-	int tmp;
 	int rc;
 
 	QETH_CARD_TEXT(card, 3, "arpstnoe");
@@ -1560,13 +1551,10 @@ static int qeth_l3_arp_set_no_entries(struct qeth_card *card, int no_entries)
 	rc = qeth_send_simple_setassparms(card, IPA_ARP_PROCESSING,
 					  IPA_CMD_ASS_ARP_SET_NO_ENTRIES,
 					  no_entries);
-	if (rc) {
-		tmp = rc;
-		QETH_DBF_MESSAGE(2, "Could not set number of ARP entries on "
-			"%s: %s (0x%x/%d)\n", QETH_CARD_IFNAME(card),
-			qeth_l3_arp_get_error_cause(&rc), tmp, tmp);
-	}
-	return rc;
+	if (rc)
+		QETH_DBF_MESSAGE(2, "Could not set number of ARP entries on device %x: %#x\n",
+				 CARD_DEVID(card), rc);
+	return qeth_l3_arp_makerc(rc);
 }
 
 static __u32 get_arp_entry_size(struct qeth_card *card,
@@ -1716,7 +1704,6 @@ static int qeth_l3_query_arp_cache_info(struct qeth_card *card,
 {
 	struct qeth_cmd_buffer *iob;
 	struct qeth_ipa_cmd *cmd;
-	int tmp;
 	int rc;
 
 	QETH_CARD_TEXT_(card, 3, "qarpipv%i", prot);
@@ -1735,15 +1722,10 @@ static int qeth_l3_query_arp_cache_info(struct qeth_card *card,
 	rc = qeth_l3_send_ipa_arp_cmd(card, iob,
 			   QETH_SETASS_BASE_LEN+QETH_ARP_CMD_LEN,
 			   qeth_l3_arp_query_cb, (void *)qinfo);
-	if (rc) {
-		tmp = rc;
-		QETH_DBF_MESSAGE(2,
-			"Error while querying ARP cache on %s: %s "
-			"(0x%x/%d)\n", QETH_CARD_IFNAME(card),
-			qeth_l3_arp_get_error_cause(&rc), tmp, tmp);
-	}
-
-	return rc;
+	if (rc)
+		QETH_DBF_MESSAGE(2, "Error while querying ARP cache on device %x: %#x\n",
+				 CARD_DEVID(card), rc);
+	return qeth_l3_arp_makerc(rc);
 }
 
 static int qeth_l3_arp_query(struct qeth_card *card, char __user *udata)
@@ -1797,8 +1779,6 @@ static int qeth_l3_arp_add_entry(struct qeth_card *card,
 				struct qeth_arp_cache_entry *entry)
 {
 	struct qeth_cmd_buffer *iob;
-	char buf[16];
-	int tmp;
 	int rc;
 
 	QETH_CARD_TEXT(card, 3, "arpadent");
@@ -1824,14 +1804,10 @@ static int qeth_l3_arp_add_entry(struct qeth_card *card,
 				   sizeof(struct qeth_arp_cache_entry),
 				   (unsigned long) entry,
 				   qeth_setassparms_cb, NULL);
-	if (rc) {
-		tmp = rc;
-		qeth_l3_ipaddr4_to_string((u8 *)entry->ipaddr, buf);
-		QETH_DBF_MESSAGE(2, "Could not add ARP entry for address %s "
-			"on %s: %s (0x%x/%d)\n", buf, QETH_CARD_IFNAME(card),
-			qeth_l3_arp_get_error_cause(&rc), tmp, tmp);
-	}
-	return rc;
+	if (rc)
+		QETH_DBF_MESSAGE(2, "Could not add ARP entry on device %x: %#x\n",
+				 CARD_DEVID(card), rc);
+	return qeth_l3_arp_makerc(rc);
 }
 
 static int qeth_l3_arp_remove_entry(struct qeth_card *card,
@@ -1839,7 +1815,6 @@ static int qeth_l3_arp_remove_entry(struct qeth_card *card,
 {
 	struct qeth_cmd_buffer *iob;
 	char buf[16] = {0, };
-	int tmp;
 	int rc;
 
 	QETH_CARD_TEXT(card, 3, "arprment");
@@ -1864,21 +1839,15 @@ static int qeth_l3_arp_remove_entry(struct qeth_card *card,
 	rc = qeth_send_setassparms(card, iob,
 				   12, (unsigned long)buf,
 				   qeth_setassparms_cb, NULL);
-	if (rc) {
-		tmp = rc;
-		memset(buf, 0, 16);
-		qeth_l3_ipaddr4_to_string((u8 *)entry->ipaddr, buf);
-		QETH_DBF_MESSAGE(2, "Could not delete ARP entry for address %s"
-			" on %s: %s (0x%x/%d)\n", buf, QETH_CARD_IFNAME(card),
-			qeth_l3_arp_get_error_cause(&rc), tmp, tmp);
-	}
-	return rc;
+	if (rc)
+		QETH_DBF_MESSAGE(2, "Could not delete ARP entry on device %x: %#x\n",
+				 CARD_DEVID(card), rc);
+	return qeth_l3_arp_makerc(rc);
 }
 
 static int qeth_l3_arp_flush_cache(struct qeth_card *card)
 {
 	int rc;
-	int tmp;
 
 	QETH_CARD_TEXT(card, 3, "arpflush");
 
@@ -1894,13 +1863,10 @@ static int qeth_l3_arp_flush_cache(struct qeth_card *card)
 	}
 	rc = qeth_send_simple_setassparms(card, IPA_ARP_PROCESSING,
 					  IPA_CMD_ASS_ARP_FLUSH_CACHE, 0);
-	if (rc) {
-		tmp = rc;
-		QETH_DBF_MESSAGE(2, "Could not flush ARP cache on %s: %s "
-			"(0x%x/%d)\n", QETH_CARD_IFNAME(card),
-			qeth_l3_arp_get_error_cause(&rc), tmp, tmp);
-	}
-	return rc;
+	if (rc)
+		QETH_DBF_MESSAGE(2, "Could not flush ARP cache on device %x: %#x\n",
+				 CARD_DEVID(card), rc);
+	return qeth_l3_arp_makerc(rc);
 }
 
 static int qeth_l3_do_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)