diff options
Diffstat (limited to 'kernel/bpf/syscall.c')
-rw-r--r-- | kernel/bpf/syscall.c | 108 |
1 files changed, 96 insertions, 12 deletions
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 84470d1480aa..afca36f53c49 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -136,21 +136,29 @@ static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) void *bpf_map_area_alloc(size_t size, int numa_node) { - /* We definitely need __GFP_NORETRY, so OOM killer doesn't - * trigger under memory pressure as we really just want to - * fail instead. + /* We really just want to fail instead of triggering OOM killer + * under memory pressure, therefore we set __GFP_NORETRY to kmalloc, + * which is used for lower order allocation requests. + * + * It has been observed that higher order allocation requests done by + * vmalloc with __GFP_NORETRY being set might fail due to not trying + * to reclaim memory from the page cache, thus we set + * __GFP_RETRY_MAYFAIL to avoid such situations. */ - const gfp_t flags = __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO; + + const gfp_t flags = __GFP_NOWARN | __GFP_ZERO; void *area; if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { - area = kmalloc_node(size, GFP_USER | flags, numa_node); + area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags, + numa_node); if (area != NULL) return area; } - return __vmalloc_node_flags_caller(size, numa_node, GFP_KERNEL | flags, - __builtin_return_address(0)); + return __vmalloc_node_flags_caller(size, numa_node, + GFP_KERNEL | __GFP_RETRY_MAYFAIL | + flags, __builtin_return_address(0)); } void bpf_map_area_free(void *area) @@ -463,7 +471,7 @@ int map_check_no_btf(const struct bpf_map *map, return -ENOTSUPP; } -static int map_check_btf(const struct bpf_map *map, const struct btf *btf, +static int map_check_btf(struct bpf_map *map, const struct btf *btf, u32 btf_key_id, u32 btf_value_id) { const struct btf_type *key_type, *value_type; @@ -478,6 +486,22 @@ static int map_check_btf(const struct bpf_map *map, const struct btf *btf, if (!value_type || value_size != map->value_size) return -EINVAL; + map->spin_lock_off = btf_find_spin_lock(btf, value_type); + + if (map_value_has_spin_lock(map)) { + if (map->map_type != BPF_MAP_TYPE_HASH && + map->map_type != BPF_MAP_TYPE_ARRAY && + map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE) + return -ENOTSUPP; + if (map->spin_lock_off + sizeof(struct bpf_spin_lock) > + map->value_size) { + WARN_ONCE(1, + "verifier bug spin_lock_off %d value_size %d\n", + map->spin_lock_off, map->value_size); + return -EFAULT; + } + } + if (map->ops->map_check_btf) ret = map->ops->map_check_btf(map, btf, key_type, value_type); @@ -542,6 +566,8 @@ static int map_create(union bpf_attr *attr) map->btf = btf; map->btf_key_type_id = attr->btf_key_type_id; map->btf_value_type_id = attr->btf_value_type_id; + } else { + map->spin_lock_off = -EINVAL; } err = security_bpf_map_alloc(map); @@ -664,7 +690,7 @@ static void *__bpf_copy_key(void __user *ukey, u64 key_size) } /* last field in 'union bpf_attr' used by this command */ -#define BPF_MAP_LOOKUP_ELEM_LAST_FIELD value +#define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags static int map_lookup_elem(union bpf_attr *attr) { @@ -680,6 +706,9 @@ static int map_lookup_elem(union bpf_attr *attr) if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) return -EINVAL; + if (attr->flags & ~BPF_F_LOCK) + return -EINVAL; + f = fdget(ufd); map = __bpf_map_get(f); if (IS_ERR(map)) @@ -690,6 +719,12 @@ static int map_lookup_elem(union bpf_attr *attr) goto err_put; } + if ((attr->flags & BPF_F_LOCK) && + !map_value_has_spin_lock(map)) { + err = -EINVAL; + goto err_put; + } + key = __bpf_copy_key(ukey, map->key_size); if (IS_ERR(key)) { err = PTR_ERR(key); @@ -745,7 +780,13 @@ static int map_lookup_elem(union bpf_attr *attr) err = -ENOENT; } else { err = 0; - memcpy(value, ptr, value_size); + if (attr->flags & BPF_F_LOCK) + /* lock 'ptr' and copy everything but lock */ + copy_map_value_locked(map, value, ptr, true); + else + copy_map_value(map, value, ptr); + /* mask lock, since value wasn't zero inited */ + check_and_init_map_lock(map, value); } rcu_read_unlock(); } @@ -808,6 +849,12 @@ static int map_update_elem(union bpf_attr *attr) goto err_put; } + if ((attr->flags & BPF_F_LOCK) && + !map_value_has_spin_lock(map)) { + err = -EINVAL; + goto err_put; + } + key = __bpf_copy_key(ukey, map->key_size); if (IS_ERR(key)) { err = PTR_ERR(key); @@ -1219,6 +1266,7 @@ static void __bpf_prog_put_rcu(struct rcu_head *rcu) static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) { if (atomic_dec_and_test(&prog->aux->refcnt)) { + perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0); /* bpf_prog_free_id() must be called first */ bpf_prog_free_id(prog, do_idr_lock); bpf_prog_kallsyms_del_all(prog); @@ -1244,24 +1292,54 @@ static int bpf_prog_release(struct inode *inode, struct file *filp) return 0; } +static void bpf_prog_get_stats(const struct bpf_prog *prog, + struct bpf_prog_stats *stats) +{ + u64 nsecs = 0, cnt = 0; + int cpu; + + for_each_possible_cpu(cpu) { + const struct bpf_prog_stats *st; + unsigned int start; + u64 tnsecs, tcnt; + + st = per_cpu_ptr(prog->aux->stats, cpu); + do { + start = u64_stats_fetch_begin_irq(&st->syncp); + tnsecs = st->nsecs; + tcnt = st->cnt; + } while (u64_stats_fetch_retry_irq(&st->syncp, start)); + nsecs += tnsecs; + cnt += tcnt; + } + stats->nsecs = nsecs; + stats->cnt = cnt; +} + #ifdef CONFIG_PROC_FS static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) { const struct bpf_prog *prog = filp->private_data; char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; + struct bpf_prog_stats stats; + bpf_prog_get_stats(prog, &stats); bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); seq_printf(m, "prog_type:\t%u\n" "prog_jited:\t%u\n" "prog_tag:\t%s\n" "memlock:\t%llu\n" - "prog_id:\t%u\n", + "prog_id:\t%u\n" + "run_time_ns:\t%llu\n" + "run_cnt:\t%llu\n", prog->type, prog->jited, prog_tag, prog->pages * 1ULL << PAGE_SHIFT, - prog->aux->id); + prog->aux->id, + stats.nsecs, + stats.cnt); } #endif @@ -1562,6 +1640,7 @@ static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr) } bpf_prog_kallsyms_add(prog); + perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0); return err; free_used_maps: @@ -2083,6 +2162,7 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info); struct bpf_prog_info info = {}; u32 info_len = attr->info.info_len; + struct bpf_prog_stats stats; char __user *uinsns; u32 ulen; int err; @@ -2122,6 +2202,10 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog, if (err) return err; + bpf_prog_get_stats(prog, &stats); + info.run_time_ns = stats.nsecs; + info.run_cnt = stats.cnt; + if (!capable(CAP_SYS_ADMIN)) { info.jited_prog_len = 0; info.xlated_prog_len = 0; |