From b81e03a24966dca0b119eff0549a4e44befff419 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Google)" Date: Tue, 19 Dec 2023 13:54:21 -0500 Subject: ring-buffer: Do no swap cpu buffers if order is different As all the subbuffer order (subbuffer sizes) must be the same throughout the ring buffer, check the order of the buffers that are doing a CPU buffer swap in ring_buffer_swap_cpu() to make sure they are the same. If the are not the same, then fail to do the swap, otherwise the ring buffer will think the CPU buffer has a specific subbuffer size when it does not. Link: https://lore.kernel.org/linux-trace-kernel/20231219185629.467894710@goodmis.org Cc: Masami Hiramatsu Cc: Mark Rutland Cc: Mathieu Desnoyers Cc: Andrew Morton Cc: Tzvetomir Stoyanov Cc: Vincent Donnefort Cc: Kent Overstreet Signed-off-by: Steven Rostedt (Google) --- kernel/trace/ring_buffer.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'kernel/trace') diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 3c11e8e811ed..fdcd171b09b5 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -5417,6 +5417,9 @@ int ring_buffer_swap_cpu(struct trace_buffer *buffer_a, if (cpu_buffer_a->nr_pages != cpu_buffer_b->nr_pages) goto out; + if (buffer_a->subbuf_order != buffer_b->subbuf_order) + goto out; + ret = -EAGAIN; if (atomic_read(&buffer_a->record_disabled)) -- cgit v1.2.3