[PATCH bpf-next] bpf: Tidy verifier bug message

[Paul Chaignon <paul.chaignon@gmail.com>]

Yonghong noticed that error messages for potential verifier bugs often
have a '(1)' at the end. This is happening because verifier_bug_if(cond,
env, fmt, args...) prints "(" #cond ")\n" as part of the message and
verifier_bug() is defined as:

  #define verifier_bug(env, fmt, args...) verifier_bug_if(1, env, fmt, ##args)

Hence, verifier_bug() always ends up displaying '(1)'. This small patch
fixes it by having verifier_bug_if conditionally call verifier_bug
instead of the other way around.

Fixes: 1cb0f56d9618 ("bpf: WARN_ONCE on verifier bugs")
Reported-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
---
 include/linux/bpf_verifier.h | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index c823f8efe3ed..d38b5ac6a191 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -876,12 +876,15 @@ __printf(3, 4) void verbose_linfo(struct bpf_verifier_env *env,
 	({											\
 		bool __cond = (cond);								\
 		if (unlikely(__cond)) {								\
-			BPF_WARN_ONCE(1, "verifier bug: " fmt "(" #cond ")\n", ##args);		\
-			bpf_log(&env->log, "verifier bug: " fmt "(" #cond ")\n", ##args);	\
+			verifier_bug(env, fmt " (" #cond ")", ##args);				\
 		}										\
 		(__cond);									\
 	})
-#define verifier_bug(env, fmt, args...) verifier_bug_if(1, env, fmt, ##args)
+#define verifier_bug(env, fmt, args...)					\
+	({								\
+		BPF_WARN_ONCE(1, "verifier bug: " fmt "\n", ##args);	\
+		bpf_log(&env->log, "verifier bug: " fmt "\n", ##args);	\
+	})
 
 static inline struct bpf_func_state *cur_func(struct bpf_verifier_env *env)
 {
-- 
2.43.0