From: Julian Wiedmann <jwi@linux.ibm.com>
Date: Mon, 23 Dec 2019 15:03:22 +0100
Subject: s390/qeth: lock the card while changing its hsuid
Git-commit: 5b6c7b55cfe26224b0f41b1c226d3534c542787f
Patch-mainline: v5.5-rc5
References: git-fixes
qeth_l3_dev_hsuid_store() initially checks the card state, but doesn't
take the conf_mutex to ensure that the card stays in this state while
being reconfigured.
Rework the code to take this lock, and drop a redundant state check in a
helper function.
Fixes: b333293058aa ("qeth: add support for af_iucv HiperSockets transport")
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[ ptesarik: All other returns under mutex also converted to gotos. ]
Signed-off-by: Petr Tesarik <ptesarik@suse.com>
---
drivers/s390/net/qeth_core_main.c | 6 -----
drivers/s390/net/qeth_l3_sys.c | 40 ++++++++++++++++++++++++++------------
2 files changed, 28 insertions(+), 18 deletions(-)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -3519,12 +3519,6 @@ int qeth_configure_cq(struct qeth_card *
goto out;
}
- if (card->state != CARD_STATE_DOWN &&
- card->state != CARD_STATE_RECOVER) {
- rc = -1;
- goto out;
- }
-
qeth_free_qdio_buffers(card);
card->options.cq = cq;
rc = 0;
--- a/drivers/s390/net/qeth_l3_sys.c
+++ b/drivers/s390/net/qeth_l3_sys.c
@@ -271,25 +271,37 @@ static ssize_t qeth_l3_dev_hsuid_store(s
struct device_attribute *attr, const char *buf, size_t count)
{
struct qeth_card *card = dev_get_drvdata(dev);
+ int rc = 0;
char *tmp;
- int rc;
if (!card)
return -EINVAL;
if (card->info.type != QETH_CARD_TYPE_IQD)
return -EPERM;
+
+ mutex_lock(&card->conf_mutex);
if (card->state != CARD_STATE_DOWN &&
- card->state != CARD_STATE_RECOVER)
- return -EPERM;
- if (card->options.sniffer)
- return -EPERM;
- if (card->options.cq == QETH_CQ_NOTAVAILABLE)
- return -EPERM;
+ card->state != CARD_STATE_RECOVER) {
+ rc = -EPERM;
+ goto out;
+ }
+
+ if (card->options.sniffer) {
+ rc = -EPERM;
+ goto out;
+ }
+
+ if (card->options.cq == QETH_CQ_NOTAVAILABLE) {
+ rc = -EPERM;
+ goto out;
+ }
tmp = strsep((char **)&buf, "\n");
- if (strlen(tmp) > 8)
- return -EINVAL;
+ if (strlen(tmp) > 8) {
+ rc = -EINVAL;
+ goto out;
+ }
if (card->options.hsuid[0])
/* delete old ip address */
@@ -300,11 +312,13 @@ static ssize_t qeth_l3_dev_hsuid_store(s
card->options.hsuid[0] = '\0';
memcpy(card->dev->perm_addr, card->options.hsuid, 9);
qeth_configure_cq(card, QETH_CQ_DISABLED);
- return count;
+ goto out;
}
- if (qeth_configure_cq(card, QETH_CQ_ENABLED))
- return -EPERM;
+ if (qeth_configure_cq(card, QETH_CQ_ENABLED)) {
+ rc = -EPERM;
+ goto out;
+ }
snprintf(card->options.hsuid, sizeof(card->options.hsuid),
"%-8s", tmp);
@@ -313,6 +327,8 @@ static ssize_t qeth_l3_dev_hsuid_store(s
rc = qeth_l3_modify_hsuid(card, true);
+out:
+ mutex_unlock(&card->conf_mutex);
return rc ? rc : count;
}