Embed nr_ids (the number of cpu for the xps cpus map, and the number of
rxqs for the xps cpus map) in dev_maps. That will help not accessing out
of bound memory if those values change after dev_maps was allocated.
Suggested-by: Alexander Duyck <alexander.du...@gmail.com>
Signed-off-by: Antoine Tenart <aten...@kernel.org>
---
include/linux/netdevice.h | 4 ++++
net/core/dev.c | 34 +++++++++++++++-------------------
net/core/net-sysfs.c | 38 ++++++++++++++++++++++----------------
3 files changed, 41 insertions(+), 35 deletions(-)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index d7d3c646d40d..40683b6eee54 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -780,6 +780,9 @@ struct xps_map {
/*
* This structure holds all XPS maps for device. Maps are indexed by CPU.
*
+ * We keep track of the number of cpus/rxqs used when the struct is allocated,
+ * in nr_ids. This will help not accessing out-of-bound memory.
+ *
* We keep track of the number of traffic classes used when the struct is
* allocated, in num_tc. This will be used to navigate the maps, to ensure
we're
* not crossing its upper bound, as the original dev->num_tc can be updated in
@@ -787,6 +790,7 @@ struct xps_map {
*/
struct xps_dev_maps {
struct rcu_head rcu;
+ unsigned int nr_ids;
s16 num_tc;
struct xps_map __rcu *attr_map[]; /* Either CPUs map or RXQs map */
};
diff --git a/net/core/dev.c b/net/core/dev.c
index 7c5e2c614723..1f7df0bd415c 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2506,14 +2506,14 @@ static void reset_xps_maps(struct net_device *dev,
}
static void clean_xps_maps(struct net_device *dev, const unsigned long *mask,
- struct xps_dev_maps *dev_maps, unsigned int nr_ids,
- u16 offset, u16 count, bool is_rxqs_map)
+ struct xps_dev_maps *dev_maps, u16 offset, u16 count,
+ bool is_rxqs_map)
{
+ unsigned int nr_ids = dev_maps->nr_ids;
bool active = false;
int i, j;
- for (j = -1; j = netif_attrmask_next(j, mask, nr_ids),
- j < nr_ids;)
+ for (j = -1; j = netif_attrmask_next(j, mask, nr_ids), j < nr_ids;)
active |= remove_xps_queue_cpu(dev, dev_maps, j, offset,
count);
if (!active)
@@ -2533,7 +2533,6 @@ static void netif_reset_xps_queues(struct net_device
*dev, u16 offset,
{
const unsigned long *possible_mask = NULL;
struct xps_dev_maps *dev_maps;
- unsigned int nr_ids;
if (!static_key_false(&xps_needed))
return;
@@ -2543,11 +2542,9 @@ static void netif_reset_xps_queues(struct net_device
*dev, u16 offset,
if (static_key_false(&xps_rxqs_needed)) {
dev_maps = xmap_dereference(dev->xps_rxqs_map);
- if (dev_maps) {
- nr_ids = dev->num_rx_queues;
- clean_xps_maps(dev, possible_mask, dev_maps, nr_ids,
- offset, count, true);
- }
+ if (dev_maps)
+ clean_xps_maps(dev, possible_mask, dev_maps, offset,
+ count, true);
}
dev_maps = xmap_dereference(dev->xps_cpus_map);
@@ -2556,9 +2553,7 @@ static void netif_reset_xps_queues(struct net_device
*dev, u16 offset,
if (num_possible_cpus() > 1)
possible_mask = cpumask_bits(cpu_possible_mask);
- nr_ids = nr_cpu_ids;
- clean_xps_maps(dev, possible_mask, dev_maps, nr_ids, offset, count,
- false);
+ clean_xps_maps(dev, possible_mask, dev_maps, offset, count, false);
out_no_maps:
mutex_unlock(&xps_map_mutex);
@@ -2672,6 +2667,7 @@ int __netif_set_xps_queue(struct net_device *dev, const
unsigned long *mask,
return -ENOMEM;
}
+ new_dev_maps->nr_ids = nr_ids;
new_dev_maps->num_tc = num_tc;
}
@@ -2786,12 +2782,12 @@ int __netif_set_xps_queue(struct net_device *dev, const
unsigned long *mask,
goto out_no_maps;
/* removes tx-queue from unused CPUs/rx-queues */
- for (j = -1; j = netif_attrmask_next(j, possible_mask, nr_ids),
- j < nr_ids;) {
+ for (j = -1; j = netif_attrmask_next(j, possible_mask,
dev_maps->nr_ids),
+ j < dev_maps->nr_ids;) {
for (i = tc, tci = j * dev_maps->num_tc; i--; tci++)
active |= remove_xps_queue(dev_maps, tci, index);
- if (!netif_attr_test_mask(j, mask, nr_ids) ||
- !netif_attr_test_online(j, online_mask, nr_ids))
+ if (!netif_attr_test_mask(j, mask, dev_maps->nr_ids) ||
+ !netif_attr_test_online(j, online_mask, dev_maps->nr_ids))
active |= remove_xps_queue(dev_maps, tci, index);
for (i = dev_maps->num_tc - tc, tci++; --i; tci++)
active |= remove_xps_queue(dev_maps, tci, index);
@@ -3947,7 +3943,7 @@ static int __get_xps_queue_idx(struct net_device *dev,
struct sk_buff *skb,
struct xps_map *map;
int queue_index = -1;
- if (tc >= dev_maps->num_tc)
+ if (tc >= dev_maps->num_tc || tci >= dev_maps->nr_ids)
return queue_index;
tci *= dev_maps->num_tc;
@@ -3986,7 +3982,7 @@ static int get_xps_queue(struct net_device *dev, struct
net_device *sb_dev,
if (dev_maps) {
int tci = sk_rx_queue_get(sk);
- if (tci >= 0 && tci < dev->num_rx_queues)
+ if (tci >= 0)
queue_index = __get_xps_queue_idx(dev, skb, dev_maps,
tci);
}
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index c1d4d3e712a9..e544e5f2467c 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -1319,9 +1319,9 @@ static ssize_t xps_cpus_show(struct netdev_queue *queue,
{
struct net_device *dev = queue->dev;
struct xps_dev_maps *dev_maps;
+ unsigned int index, nr_ids;
int j, len, ret, tc = 0;
unsigned long *mask;
- unsigned int index;
if (!netif_is_multiqueue(dev))
return -ENOENT;
@@ -1340,19 +1340,20 @@ static ssize_t xps_cpus_show(struct netdev_queue *queue,
goto err_rtnl_unlock;
}
- mask = bitmap_zalloc(nr_cpu_ids, GFP_KERNEL);
+ rcu_read_lock();
+ dev_maps = rcu_dereference(dev->xps_cpus_map);
+ nr_ids = dev_maps ? dev_maps->nr_ids : nr_cpu_ids;
+
+ mask = bitmap_zalloc(nr_ids, GFP_KERNEL);
if (!mask) {
ret = -ENOMEM;
- goto err_rtnl_unlock;
+ goto err_rcu_unlock;
}
- rcu_read_lock();
- dev_maps = rcu_dereference(dev->xps_cpus_map);
if (!dev_maps || tc >= dev_maps->num_tc)
goto out_no_maps;
- for (j = -1; j = netif_attrmask_next(j, NULL, nr_cpu_ids),
- j < nr_cpu_ids;) {
+ for (j = -1; j = netif_attrmask_next(j, NULL, nr_ids), j < nr_ids;) {
int i, tci = j * dev_maps->num_tc + tc;
struct xps_map *map;
@@ -1372,10 +1373,12 @@ static ssize_t xps_cpus_show(struct netdev_queue *queue,
rtnl_unlock();
- len = bitmap_print_to_pagebuf(false, buf, mask, nr_cpu_ids);
+ len = bitmap_print_to_pagebuf(false, buf, mask, nr_ids);
bitmap_free(mask);
return len < PAGE_SIZE ? len : -EINVAL;
+err_rcu_unlock:
+ rcu_read_unlock();
err_rtnl_unlock:
rtnl_unlock();
return ret;
@@ -1426,9 +1429,9 @@ static ssize_t xps_rxqs_show(struct netdev_queue *queue,
char *buf)
{
struct net_device *dev = queue->dev;
struct xps_dev_maps *dev_maps;
+ unsigned int index, nr_ids;
int j, len, ret, tc = 0;
unsigned long *mask;
- unsigned int index;
index = get_netdev_queue_index(queue);
@@ -1441,19 +1444,20 @@ static ssize_t xps_rxqs_show(struct netdev_queue
*queue, char *buf)
goto err_rtnl_unlock;
}
- mask = bitmap_zalloc(dev->num_rx_queues, GFP_KERNEL);
+ rcu_read_lock();
+ dev_maps = rcu_dereference(dev->xps_rxqs_map);
+ nr_ids = dev_maps ? dev_maps->nr_ids : dev->num_rx_queues;
+
+ mask = bitmap_zalloc(nr_ids, GFP_KERNEL);
if (!mask) {
ret = -ENOMEM;
- goto err_rtnl_unlock;
+ goto err_rcu_unlock;
}
- rcu_read_lock();
- dev_maps = rcu_dereference(dev->xps_rxqs_map);
if (!dev_maps || tc >= dev_maps->num_tc)
goto out_no_maps;
- for (j = -1; j = netif_attrmask_next(j, NULL, dev->num_rx_queues),
- j < dev->num_rx_queues;) {
+ for (j = -1; j = netif_attrmask_next(j, NULL, nr_ids), j < nr_ids;) {
int i, tci = j * dev_maps->num_tc + tc;
struct xps_map *map;
@@ -1473,11 +1477,13 @@ static ssize_t xps_rxqs_show(struct netdev_queue
*queue, char *buf)
rtnl_unlock();
- len = bitmap_print_to_pagebuf(false, buf, mask, dev->num_rx_queues);
+ len = bitmap_print_to_pagebuf(false, buf, mask, nr_ids);
bitmap_free(mask);
return len < PAGE_SIZE ? len : -EINVAL;
+err_rcu_unlock:
+ rcu_read_unlock();
err_rtnl_unlock:
rtnl_unlock();
return ret;
--
2.29.2
