From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Thu, 31 Oct 2024 15:20:56 +0000 (-0400)
Subject: tracing: Add might_fault() check in __DECLARE_TRACE_SYSCALL
X-Git-Tag: v6.13-rc1~115^2~8
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=ee3685a98ea920369696d31e54d1fe6a939ed65f;p=linux-block.git

tracing: Add might_fault() check in __DECLARE_TRACE_SYSCALL

Catch incorrect use of syscall tracepoints even if no probes are
registered by adding a might_fault() check in trace_##name()
emitted by __DECLARE_TRACE_SYSCALL.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jordan Rife <jrife@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Michael Jeanson <mjeanson@efficios.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Yonghong Song <yhs@fb.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc: bpf@vger.kernel.org
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Jordan Rife <jrife@google.com>
Cc: linux-trace-kernel@vger.kernel.org
Link: https://lore.kernel.org/20241031152056.744137-5-mathieu.desnoyers@efficios.com
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---

diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index 906f3091d23d..425123e921ac 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -301,6 +301,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p)
 	__DECLARE_TRACE_COMMON(name, PARAMS(proto), PARAMS(args), cond, PARAMS(data_proto)) \
 	static inline void trace_##name(proto)				\
 	{								\
+		might_fault();						\
 		if (static_branch_unlikely(&__tracepoint_##name.key))	\
 			__DO_TRACE(name,				\
 				TP_ARGS(args),				\