diff options
| -rw-r--r-- | mm/kasan/quarantine.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/mm/kasan/quarantine.c b/mm/kasan/quarantine.c index 4c5375810449..0e3f8494628f 100644 --- a/mm/kasan/quarantine.c +++ b/mm/kasan/quarantine.c @@ -29,6 +29,7 @@ #include <linux/srcu.h> #include <linux/string.h> #include <linux/types.h> +#include <linux/cpuhotplug.h> #include "../slab.h" #include "kasan.h" @@ -43,6 +44,7 @@ struct qlist_head { struct qlist_node *head; struct qlist_node *tail; size_t bytes; + bool offline; }; #define QLIST_INIT { NULL, NULL, 0 } @@ -188,6 +190,10 @@ void quarantine_put(struct kasan_free_meta *info, struct kmem_cache *cache) local_irq_save(flags); q = this_cpu_ptr(&cpu_quarantine); + if (q->offline) { + local_irq_restore(flags); + return; + } qlist_put(q, &info->quarantine_link, cache->size); if (unlikely(q->bytes > QUARANTINE_PERCPU_SIZE)) { qlist_move_all(q, &temp); @@ -328,3 +334,36 @@ void quarantine_remove_cache(struct kmem_cache *cache) synchronize_srcu(&remove_cache_srcu); } + +static int kasan_cpu_online(unsigned int cpu) +{ + this_cpu_ptr(&cpu_quarantine)->offline = false; + return 0; +} + +static int kasan_cpu_offline(unsigned int cpu) +{ + struct qlist_head *q; + + q = this_cpu_ptr(&cpu_quarantine); + /* Ensure the ordering between the writing to q->offline and + * qlist_free_all. Otherwise, cpu_quarantine may be corrupted + * by interrupt. + */ + WRITE_ONCE(q->offline, true); + barrier(); + qlist_free_all(q, NULL); + return 0; +} + +static int __init kasan_cpu_quarantine_init(void) +{ + int ret = 0; + + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "mm/kasan:online", + kasan_cpu_online, kasan_cpu_offline); + if (ret < 0) + pr_err("kasan cpu quarantine register failed [%d]\n", ret); + return ret; +} +late_initcall(kasan_cpu_quarantine_init); |