From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7892010794 for ; Thu, 27 Jul 2023 15:08:41 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8082B3A9F for ; Thu, 27 Jul 2023 08:08:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1690470506; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=sobXbax/DXLXyfozu4NQWK9bV5IWun7S0SuuSyLNYyc=; b=HtQ48fjV4Urong7dpRGh7LXlZ7kekQ2cMC+x7zSU6z4dWAqFEH0HB8EhcVNCvXaIskfZa6 e7RFFGW8c/xORRkWJByK30PSRheTRFa9TnTfD9m2ul5+dr/ZJamGWahBmH14FjdRj7Raqk WuDfwb5p3yYWjwOkUiw3v8s8CpN/lvQ= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-569-K5ZXzCD6N62hni0nT3q2ng-1; Thu, 27 Jul 2023 11:08:22 -0400 X-MC-Unique: K5ZXzCD6N62hni0nT3q2ng-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 67C508564EF; Thu, 27 Jul 2023 15:08:22 +0000 (UTC) Received: from astarta.redhat.com (unknown [10.39.194.232]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AFA8F492C13; Thu, 27 Jul 2023 15:08:21 +0000 (UTC) From: Yauheni Kaliuta To: bpf@vger.kernel.org Cc: andrii@kernel.org, ast@kernel.org Subject: Re: [PATCH] tracing: perf_call_bpf: use struct trace_entry in struct syscall_tp_t References: <20230727150534.397532-1-ykaliuta@redhat.com> Date: Thu, 27 Jul 2023 18:08:20 +0300 In-Reply-To: <20230727150534.397532-1-ykaliuta@redhat.com> (Yauheni Kaliuta's message of "Thu, 27 Jul 2023 18:05:34 +0300") Message-ID: Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Resending with proper subject. >>>>> On Thu, 27 Jul 2023 18:05:34 +0300, Yauheni Kaliuta wrote: > bpf tracepoint program uses struct trace_event_raw_sys_enter as > argument where trace_entry is the first field. Use the same instead > of unsigned long long since if it's amended (for example by RT > patch) it accesses data with wrong offset. > Signed-off-by: Yauheni Kaliuta > --- > kernel/trace/trace_syscalls.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c > index 942ddbdace4a..07f4fa395e99 100644 > --- a/kernel/trace/trace_syscalls.c > +++ b/kernel/trace/trace_syscalls.c > @@ -555,12 +555,15 @@ static int perf_call_bpf_enter(struct trace_event_call *call, struct pt_regs *re > struct syscall_trace_enter *rec) > { > struct syscall_tp_t { > - unsigned long long regs; > + struct trace_entry ent; > unsigned long syscall_nr; > unsigned long args[SYSCALL_DEFINE_MAXARGS]; > } param; > int i; > + BUILD_BUG_ON(sizeof(param.ent) < sizeof(void *)); > + > + /* __bpf_prog_run() requires *regs as the first parameter */ > *(struct pt_regs **)¶m = regs; > param.syscall_nr = rec->nr; > for (i = 0; i < sys_data->nb_args; i++) > @@ -657,11 +660,14 @@ static int perf_call_bpf_exit(struct trace_event_call *call, struct pt_regs *reg > struct syscall_trace_exit *rec) > { > struct syscall_tp_t { > - unsigned long long regs; > + struct trace_entry ent; > unsigned long syscall_nr; > unsigned long ret; > } param; > + BUILD_BUG_ON(sizeof(param.ent) < sizeof(void *)); > + > + /* __bpf_prog_run() requires *regs as the first parameter */ > *(struct pt_regs **)¶m = regs; > param.syscall_nr = rec->nr; > param.ret = rec->ret; > -- > 2.41.0 -- WBR, Yauheni Kaliuta