bpf: minor cleanups in ebpf code

Besides others, remove redundant comments where the code is self
documenting enough, and properly indent various bpf_verifier_ops
and bpf_prog_type_list declarations. Moreover, remove two exports
that actually have no module user.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 15 insertions, 21 deletions

diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index d781b077431f..5313d09d4b62 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -129,14 +129,12 @@ struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
 
         return fp;
 }
-EXPORT_SYMBOL_GPL(bpf_prog_realloc);
 
 void __bpf_prog_free(struct bpf_prog *fp)
 {
         kfree(fp->aux);
         vfree(fp);
 }
-EXPORT_SYMBOL_GPL(__bpf_prog_free);
 
 #ifdef CONFIG_BPF_JIT
 struct bpf_binary_header *
diff --git a/net/core/filter.c b/net/core/filter.c
index 71c2a1f473ad..ea51b479cf02 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -2069,16 +2069,12 @@ tc_cls_act_func_proto(enum bpf_func_id func_id)
 
 static bool __is_valid_access(int off, int size, enum bpf_access_type type)
 {
-        /* check bounds */
         if (off < 0 || off >= sizeof(struct __sk_buff))
                 return false;
-
-        /* disallow misaligned access */
+        /* The verifier guarantees that size > 0. */
         if (off % size != 0)
                 return false;
-
-        /* all __sk_buff fields are __u32 */
-        if (size != 4)
+        if (size != sizeof(__u32))
                 return false;
 
         return true;
@@ -2097,7 +2093,7 @@ static bool sk_filter_is_valid_access(int off, int size,
         if (type == BPF_WRITE) {
                 switch (off) {
                 case offsetof(struct __sk_buff, cb[0]) ...
-                        offsetof(struct __sk_buff, cb[4]):
+                     offsetof(struct __sk_buff, cb[4]):
                         break;
                 default:
                         return false;
@@ -2278,30 +2274,30 @@ static u32 bpf_net_convert_ctx_access(enum bpf_access_type type, int dst_reg,
 }
 
 static const struct bpf_verifier_ops sk_filter_ops = {
-        .get_func_proto = sk_filter_func_proto,
-        .is_valid_access = sk_filter_is_valid_access,
-        .convert_ctx_access = bpf_net_convert_ctx_access,
+        .get_func_proto         = sk_filter_func_proto,
+        .is_valid_access        = sk_filter_is_valid_access,
+        .convert_ctx_access     = bpf_net_convert_ctx_access,
 };
 
 static const struct bpf_verifier_ops tc_cls_act_ops = {
-        .get_func_proto = tc_cls_act_func_proto,
-        .is_valid_access = tc_cls_act_is_valid_access,
-        .convert_ctx_access = bpf_net_convert_ctx_access,
+        .get_func_proto         = tc_cls_act_func_proto,
+        .is_valid_access        = tc_cls_act_is_valid_access,
+        .convert_ctx_access     = bpf_net_convert_ctx_access,
 };
 
 static struct bpf_prog_type_list sk_filter_type __read_mostly = {
-        .ops = &sk_filter_ops,
-        .type = BPF_PROG_TYPE_SOCKET_FILTER,
+        .ops    = &sk_filter_ops,
+        .type   = BPF_PROG_TYPE_SOCKET_FILTER,
 };
 
 static struct bpf_prog_type_list sched_cls_type __read_mostly = {
-        .ops = &tc_cls_act_ops,
-        .type = BPF_PROG_TYPE_SCHED_CLS,
+        .ops    = &tc_cls_act_ops,
+        .type   = BPF_PROG_TYPE_SCHED_CLS,
 };
 
 static struct bpf_prog_type_list sched_act_type __read_mostly = {
-        .ops = &tc_cls_act_ops,
-        .type = BPF_PROG_TYPE_SCHED_ACT,
+        .ops    = &tc_cls_act_ops,
+        .type   = BPF_PROG_TYPE_SCHED_ACT,
 };
 
 static int __init register_sk_filter_ops(void)