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 <[email protected]>
Tested-by: Jordan Rife <[email protected]>
Signed-off-by: Mathieu Desnoyers <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Michael Jeanson <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Yonghong Song <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Andrii Nakryiko <[email protected]>
Cc: [email protected]
Cc: Joel Fernandes <[email protected]>
Cc: Jordan Rife <[email protected]>
Cc: [email protected]
---
Changes since v4:
- Move might_fault() to trace_##name() emitted by __DECLARE_TRACE_SYSCALL
  so it is validated even when the tracepoint is disabled.
---
 include/linux/tracepoint.h | 1 +
 1 file changed, 1 insertion(+)

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),                          \
-- 
2.39.5


Reply via email to