Merge branch 'bpf-verifier-log-btf-prep'

Martin KaFai Lau says:

====================
This patch set has some changes and clean-up works for
the bpf_verifier_log.  They are the prep works for the
BTF (BPF Type Format).
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

2 files changed, 22 insertions, 12 deletions

diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 6b66cd1aa0b9..7e61c395fddf 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -153,7 +153,7 @@ struct bpf_insn_aux_data {
 
 #define BPF_VERIFIER_TMP_LOG_SIZE	1024
 
-struct bpf_verifer_log {
+struct bpf_verifier_log {
 	u32 level;
 	char kbuf[BPF_VERIFIER_TMP_LOG_SIZE];
 	char __user *ubuf;
@@ -161,11 +161,16 @@ struct bpf_verifer_log {
 	u32 len_total;
 };
 
-static inline bool bpf_verifier_log_full(const struct bpf_verifer_log *log)
+static inline bool bpf_verifier_log_full(const struct bpf_verifier_log *log)
 {
 	return log->len_used >= log->len_total - 1;
 }
 
+static inline bool bpf_verifier_log_needed(const struct bpf_verifier_log *log)
+{
+	return log->level && log->ubuf && !bpf_verifier_log_full(log);
+}
+
 #define BPF_MAX_SUBPROGS 256
 
 /* single container for all structs
@@ -185,13 +190,15 @@ struct bpf_verifier_env {
 	bool allow_ptr_leaks;
 	bool seen_direct_write;
 	struct bpf_insn_aux_data *insn_aux_data; /* array of per-insn state */
-	struct bpf_verifer_log log;
+	struct bpf_verifier_log log;
 	u32 subprog_starts[BPF_MAX_SUBPROGS];
 	/* computes the stack depth of each bpf function */
 	u16 subprog_stack_depth[BPF_MAX_SUBPROGS + 1];
 	u32 subprog_cnt;
 };
 
+void bpf_verifier_vlog(struct bpf_verifier_log *log, const char *fmt,
+		       va_list args);
 __printf(2, 3) void bpf_verifier_log_write(struct bpf_verifier_env *env,
 					   const char *fmt, ...);
 
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index e93a6e48641b..8acd2207e412 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -168,15 +168,11 @@ struct bpf_call_arg_meta {
 
 static DEFINE_MUTEX(bpf_verifier_lock);
 
-static void log_write(struct bpf_verifier_env *env, const char *fmt,
-		      va_list args)
+void bpf_verifier_vlog(struct bpf_verifier_log *log, const char *fmt,
+		       va_list args)
 {
-	struct bpf_verifer_log *log = &env->log;
 	unsigned int n;
 
-	if (!log->level || !log->ubuf || bpf_verifier_log_full(log))
-		return;
-
 	n = vscnprintf(log->kbuf, BPF_VERIFIER_TMP_LOG_SIZE, fmt, args);
 
 	WARN_ONCE(n >= BPF_VERIFIER_TMP_LOG_SIZE - 1,
@@ -200,18 +196,25 @@ __printf(2, 3) void bpf_verifier_log_write(struct bpf_verifier_env *env,
 {
 	va_list args;
 
+	if (!bpf_verifier_log_needed(&env->log))
+		return;
+
 	va_start(args, fmt);
-	log_write(env, fmt, args);
+	bpf_verifier_vlog(&env->log, fmt, args);
 	va_end(args);
 }
 EXPORT_SYMBOL_GPL(bpf_verifier_log_write);
 
 __printf(2, 3) static void verbose(void *private_data, const char *fmt, ...)
 {
+	struct bpf_verifier_env *env = private_data;
 	va_list args;
 
+	if (!bpf_verifier_log_needed(&env->log))
+		return;
+
 	va_start(args, fmt);
-	log_write(private_data, fmt, args);
+	bpf_verifier_vlog(&env->log, fmt, args);
 	va_end(args);
 }
 
@@ -5611,7 +5614,7 @@ static void free_states(struct bpf_verifier_env *env)
 int bpf_check(struct bpf_prog **prog, union bpf_attr *attr)
 {
 	struct bpf_verifier_env *env;
-	struct bpf_verifer_log *log;
+	struct bpf_verifier_log *log;
 	int ret = -EINVAL;
 
 	/* no program is valid */