Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf...

[platform/kernel/linux-rpi.git] / kernel / bpf / verifier.c

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 930b555..0b9da95 100644 (file)
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -25,6 +25,7 @@
 #include <linux/btf_ids.h>
 #include <linux/poison.h>
 #include <linux/module.h>
+#include <linux/cpumask.h>
 
 #include "disasm.h"
 
@@ -6067,6 +6068,11 @@ static int check_ptr_to_btf_access(struct bpf_verifier_env *env,
                                   type_is_rcu_or_null(env, reg, field_name, btf_id)) {
                                /* __rcu tagged pointers can be NULL */
                                flag |= MEM_RCU | PTR_MAYBE_NULL;
+
+                               /* We always trust them */
+                               if (type_is_rcu_or_null(env, reg, field_name, btf_id) &&
+                                   flag & PTR_UNTRUSTED)
+                                       flag &= ~PTR_UNTRUSTED;
                        } else if (flag & (MEM_PERCPU | MEM_USER)) {
                                /* keep as-is */
                        } else {
@@ -9117,19 +9123,33 @@ static void do_refine_retval_range(struct bpf_reg_state *regs, int ret_type,
 {
        struct bpf_reg_state *ret_reg = &regs[BPF_REG_0];
 
-       if (ret_type != RET_INTEGER ||
-           (func_id != BPF_FUNC_get_stack &&
-            func_id != BPF_FUNC_get_task_stack &&
-            func_id != BPF_FUNC_probe_read_str &&
-            func_id != BPF_FUNC_probe_read_kernel_str &&
-            func_id != BPF_FUNC_probe_read_user_str))
+       if (ret_type != RET_INTEGER)
                return;
 
-       ret_reg->smax_value = meta->msize_max_value;
-       ret_reg->s32_max_value = meta->msize_max_value;
-       ret_reg->smin_value = -MAX_ERRNO;
-       ret_reg->s32_min_value = -MAX_ERRNO;
-       reg_bounds_sync(ret_reg);
+       switch (func_id) {
+       case BPF_FUNC_get_stack:
+       case BPF_FUNC_get_task_stack:
+       case BPF_FUNC_probe_read_str:
+       case BPF_FUNC_probe_read_kernel_str:
+       case BPF_FUNC_probe_read_user_str:
+               ret_reg->smax_value = meta->msize_max_value;
+               ret_reg->s32_max_value = meta->msize_max_value;
+               ret_reg->smin_value = -MAX_ERRNO;
+               ret_reg->s32_min_value = -MAX_ERRNO;
+               reg_bounds_sync(ret_reg);
+               break;
+       case BPF_FUNC_get_smp_processor_id:
+               ret_reg->umax_value = nr_cpu_ids - 1;
+               ret_reg->u32_max_value = nr_cpu_ids - 1;
+               ret_reg->smax_value = nr_cpu_ids - 1;
+               ret_reg->s32_max_value = nr_cpu_ids - 1;
+               ret_reg->umin_value = 0;
+               ret_reg->u32_min_value = 0;
+               ret_reg->smin_value = 0;
+               ret_reg->s32_min_value = 0;
+               reg_bounds_sync(ret_reg);
+               break;
+       }
 }
 
 static int