[PATCH AUTOSEL for 4.9 45/50] s390/qeth: fix retrieval of vipa and proxy-arp addresses

From: Levin, Alexander (Sasha Levin)
Date: Tue Oct 24 2017 - 21:58:16 EST


From: Ursula Braun <ubraun@xxxxxxxxxxxxxxxxxx>

[ Upstream commit e48b9eaaa29a0a7d5da2df136b07eefa0180d584 ]

qeth devices in layer3 mode need a separate handling of vipa and proxy-arp
addresses. vipa and proxy-arp addresses processed by qeth can be read from
userspace. Introduced with commit 5f78e29ceebf ("qeth: optimize IP handling
in rx_mode callback") the retrieval of vipa and proxy-arp addresses is
broken, if more than one vipa or proxy-arp address are set.

The qeth code used local variable "int i" for 2 different purposes. This
patch now spends 2 separate local variables of type "int".
While touching these functions hash_for_each_safe() is converted to
hash_for_each(), since there is no removal of hash entries.

Signed-off-by: Ursula Braun <ubraun@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Julian Wiedmann <jwi@xxxxxxxxxxxxxxxxxx>
Reference-ID: RQM 3524
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
drivers/s390/net/qeth_l3_sys.c | 30 ++++++++++++++++--------------
1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/drivers/s390/net/qeth_l3_sys.c b/drivers/s390/net/qeth_l3_sys.c
index 0e00a5ce0f00..cffe42f5775d 100644
--- a/drivers/s390/net/qeth_l3_sys.c
+++ b/drivers/s390/net/qeth_l3_sys.c
@@ -692,15 +692,15 @@ static ssize_t qeth_l3_dev_vipa_add_show(char *buf, struct qeth_card *card,
enum qeth_prot_versions proto)
{
struct qeth_ipaddr *ipaddr;
- struct hlist_node *tmp;
char addr_str[40];
+ int str_len = 0;
int entry_len; /* length of 1 entry string, differs between v4 and v6 */
- int i = 0;
+ int i;

entry_len = (proto == QETH_PROT_IPV4)? 12 : 40;
entry_len += 2; /* \n + terminator */
spin_lock_bh(&card->ip_lock);
- hash_for_each_safe(card->ip_htable, i, tmp, ipaddr, hnode) {
+ hash_for_each(card->ip_htable, i, ipaddr, hnode) {
if (ipaddr->proto != proto)
continue;
if (ipaddr->type != QETH_IP_TYPE_VIPA)
@@ -708,16 +708,17 @@ static ssize_t qeth_l3_dev_vipa_add_show(char *buf, struct qeth_card *card,
/* String must not be longer than PAGE_SIZE. So we check if
* string length gets near PAGE_SIZE. Then we can savely display
* the next IPv6 address (worst case, compared to IPv4) */
- if ((PAGE_SIZE - i) <= entry_len)
+ if ((PAGE_SIZE - str_len) <= entry_len)
break;
qeth_l3_ipaddr_to_string(proto, (const u8 *)&ipaddr->u,
addr_str);
- i += snprintf(buf + i, PAGE_SIZE - i, "%s\n", addr_str);
+ str_len += snprintf(buf + str_len, PAGE_SIZE - str_len, "%s\n",
+ addr_str);
}
spin_unlock_bh(&card->ip_lock);
- i += snprintf(buf + i, PAGE_SIZE - i, "\n");
+ str_len += snprintf(buf + str_len, PAGE_SIZE - str_len, "\n");

- return i;
+ return str_len;
}

static ssize_t qeth_l3_dev_vipa_add4_show(struct device *dev,
@@ -854,15 +855,15 @@ static ssize_t qeth_l3_dev_rxip_add_show(char *buf, struct qeth_card *card,
enum qeth_prot_versions proto)
{
struct qeth_ipaddr *ipaddr;
- struct hlist_node *tmp;
char addr_str[40];
+ int str_len = 0;
int entry_len; /* length of 1 entry string, differs between v4 and v6 */
- int i = 0;
+ int i;

entry_len = (proto == QETH_PROT_IPV4)? 12 : 40;
entry_len += 2; /* \n + terminator */
spin_lock_bh(&card->ip_lock);
- hash_for_each_safe(card->ip_htable, i, tmp, ipaddr, hnode) {
+ hash_for_each(card->ip_htable, i, ipaddr, hnode) {
if (ipaddr->proto != proto)
continue;
if (ipaddr->type != QETH_IP_TYPE_RXIP)
@@ -870,16 +871,17 @@ static ssize_t qeth_l3_dev_rxip_add_show(char *buf, struct qeth_card *card,
/* String must not be longer than PAGE_SIZE. So we check if
* string length gets near PAGE_SIZE. Then we can savely display
* the next IPv6 address (worst case, compared to IPv4) */
- if ((PAGE_SIZE - i) <= entry_len)
+ if ((PAGE_SIZE - str_len) <= entry_len)
break;
qeth_l3_ipaddr_to_string(proto, (const u8 *)&ipaddr->u,
addr_str);
- i += snprintf(buf + i, PAGE_SIZE - i, "%s\n", addr_str);
+ str_len += snprintf(buf + str_len, PAGE_SIZE - str_len, "%s\n",
+ addr_str);
}
spin_unlock_bh(&card->ip_lock);
- i += snprintf(buf + i, PAGE_SIZE - i, "\n");
+ str_len += snprintf(buf + str_len, PAGE_SIZE - str_len, "\n");

- return i;
+ return str_len;
}

static ssize_t qeth_l3_dev_rxip_add4_show(struct device *dev,
--
2.11.0