perf/x86/intel/bts: Replace offsetof() with struct_size()

Use struct_size() to calculate the number of bytes to allocate for a new
bts_buffer. Compared to offsetof(), struct_size() provides additional
compile-time checks (e.g., __must_be_array()).

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250413104108.49142-2-thorsten.blum@linux.dev

diff --git a/arch/x86/events/intel/bts.c b/arch/x86/events/intel/bts.c
index da03f53bfa184606cd25ab40635dbb22efbb4cbc..16bc89c8023b34e016135b923cc004301cabea98 100644 (file)
--- a/arch/x86/events/intel/bts.c
+++ b/arch/x86/events/intel/bts.c
@@ -101,7 +101,7 @@ bts_buffer_setup_aux(struct perf_event *event, void **pages,
        if (overwrite && nr_buf > 1)
                return NULL;
 
-       bb = kzalloc_node(offsetof(struct bts_buffer, buf[nr_buf]), GFP_KERNEL, node);
+       bb = kzalloc_node(struct_size(bb, buf, nr_buf), GFP_KERNEL, node);
        if (!bb)
                return NULL;