From: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> commit e38e2c6a9efc435f9de344b7c91f7697e01b47d5 upstream. Fix to update dynamic data counter ('dyndata') and max length ('maxlen') only if the fetcharg uses the dynamic data. Also get out arg->dynamic from unlikely(). This makes dynamic data address wrong if process_fetch_insn() returns error on !arg->dynamic case. Link: https://lore.kernel.org/all/168908494781.123124.8160245359962103684.stgit@devnote2/ Suggested-by: Steven Rostedt <rostedt@xxxxxxxxxxx> Link: https://lore.kernel.org/all/20230710233400.5aaf024e@xxxxxxxxxxxxxxxxxx/ Fixes: 9178412ddf5a ("tracing: probeevent: Return consumed bytes of dynamic area") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> Reviewed-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/trace/trace_probe_tmpl.h | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/kernel/trace/trace_probe_tmpl.h +++ b/kernel/trace/trace_probe_tmpl.h @@ -206,11 +206,13 @@ store_trace_args(void *data, struct trac if (unlikely(arg->dynamic)) *dl = make_data_loc(maxlen, dyndata - base); ret = process_fetch_insn(arg->code, rec, dl, base); - if (unlikely(ret < 0 && arg->dynamic)) { - *dl = make_data_loc(0, dyndata - base); - } else { - dyndata += ret; - maxlen -= ret; + if (arg->dynamic) { + if (unlikely(ret < 0)) { + *dl = make_data_loc(0, dyndata - base); + } else { + dyndata += ret; + maxlen -= ret; + } } } }