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 | 26 +++++++++++---------------
net/core/net-sysfs.c | 4 ++--
3 files changed, 17 insertions(+), 17 deletions(-)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 481307de6983..f923eb97c446 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 118cc0985ff1..2a0a777390c6 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2505,14 +2505,14 @@ 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)
@@ -2532,7 +2532,6 @@ 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;
@@ -2542,11 +2541,9 @@ 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);
@@ -2555,9 +2552,7 @@ 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);
@@ -2690,6 +2685,7 @@ 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;
}
@@ -3943,7 +3939,7 @@ 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;
@@ -3982,7 +3978,7 @@ 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 f606f3556ad7..5b7123d3b66f 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -1331,16 +1331,16 @@ static int xps_queue_show(struct net_device *dev,
unsigned long **mask,
if (is_rxqs_map) {
dev_maps = rcu_dereference(dev->xps_rxqs_map);
- nr_ids = dev->num_rx_queues;
} else {
dev_maps = rcu_dereference(dev->xps_cpus_map);
- nr_ids = nr_cpu_ids;
if (num_possible_cpus() > 1)
possible_mask = cpumask_bits(cpu_possible_mask);
}
if (!dev_maps || tc >= dev_maps->num_tc)
goto rcu_unlock;
+ nr_ids = dev_maps->nr_ids;
+
for (j = -1; j = netif_attrmask_next(j, possible_mask, nr_ids),
j < nr_ids;) {
int i, tci = j * dev_maps->num_tc + tc;
--
2.29.2
