media: dvb_ca_en50221: prevent using slot_info for Spectre attacs

[mirror_ubuntu-bionic-kernel.git] / mm / memcontrol.c

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index ac2ffd5e02b914fb9564649c9475babc51119de6..fd82b0e5742a021f6de66953b6e7e9956782ae23 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -879,7 +879,7 @@ static void invalidate_reclaim_iterators(struct mem_cgroup *dead_memcg)
        int nid;
        int i;
 
-       while ((memcg = parent_mem_cgroup(memcg))) {
+       for (; memcg; memcg = parent_mem_cgroup(memcg)) {
                for_each_node(nid) {
                        mz = mem_cgroup_nodeinfo(memcg, nid);
                        for (i = 0; i <= DEF_PRIORITY; i++) {
@@ -2205,7 +2205,7 @@ static void __memcg_schedule_kmem_cache_create(struct mem_cgroup *memcg,
 {
        struct memcg_kmem_cache_create_work *cw;
 
-       cw = kmalloc(sizeof(*cw), GFP_NOWAIT);
+       cw = kmalloc(sizeof(*cw), GFP_NOWAIT | __GFP_NOWARN);
        if (!cw)
                return;
 
@@ -4187,6 +4187,9 @@ static void free_mem_cgroup_per_node_info(struct mem_cgroup *memcg, int node)
 {
        struct mem_cgroup_per_node *pn = memcg->nodeinfo[node];
 
+       if (!pn)
+               return;
+
        free_percpu(pn->lruvec_stat);
        kfree(pn);
 }
@@ -5828,6 +5831,20 @@ void mem_cgroup_sk_alloc(struct sock *sk)
        if (!mem_cgroup_sockets_enabled)
                return;
 
+       /*
+        * Socket cloning can throw us here with sk_memcg already
+        * filled. It won't however, necessarily happen from
+        * process context. So the test for root memcg given
+        * the current task's memcg won't help us in this case.
+        *
+        * Respecting the original socket's memcg is a better
+        * decision in this case.
+        */
+       if (sk->sk_memcg) {
+               css_get(&sk->sk_memcg->css);
+               return;
+       }
+
        rcu_read_lock();
        memcg = mem_cgroup_from_task(current);
        if (memcg == root_mem_cgroup)