From patchwork Tue Jul 11 02:11:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13307970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F3850EB64D9 for ; Tue, 11 Jul 2023 02:11:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231533AbjGKCLy (ORCPT ); Mon, 10 Jul 2023 22:11:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58666 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231503AbjGKCLu (ORCPT ); Mon, 10 Jul 2023 22:11:50 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B9AA7E47; Mon, 10 Jul 2023 19:11:46 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 3C672612D8; Tue, 11 Jul 2023 02:11:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 40BD8C433C7; Tue, 11 Jul 2023 02:11:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1689041505; bh=dyGyLJr8vd+bW4LxAKW9oZijQiFuiaTQ8/8k42bABvk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DeRKMbFR46yWLVqZlbFemJTwHS3Vm0RrRZ1idmE/FkP0AHbmelEGghaBFLF+C4iH/ lG8osBDSPZhcH6IphWUijV2duyUI+cN3fi4Y2bV8kZW3mU/pcAB5524f5GSlVjXwpG NJ24pNB+oXEMj5lxoXP8wleqKp+9NKAck6RGgSTG44+MhRqy4SG2ZfOLe1x7j8g9xV ZAFlQOwJ5kZsyFYCfg5PRqNROPeL6Pn3g2VXoUl9izSbzMbbNTtHYa6q0EwO/ilIzu YcIKJFJI9BmXlpbhUZ6y7NbczqbHleCI6+HeQ5dK8XLY29q8L4gaMICYJBxph7w1GC U4ITF8dF1NJSA== From: "Masami Hiramatsu (Google)" To: Steven Rostedt Cc: Dan Carpenter , linux-trace-kernel@vger.kernel.org, LKML , Masami Hiramatsu Subject: [PATCH v4 3/4] Revert "tracing: Add "(fault)" name injection to kernel probes" Date: Tue, 11 Jul 2023 11:11:42 +0900 Message-ID: <168904150193.2908673.2202766623358215003.stgit@mhiramat.roam.corp.google.com> X-Mailer: git-send-email 2.41.0.255.g8b1d071c50-goog In-Reply-To: <168904147563.2908673.18054267804278861545.stgit@mhiramat.roam.corp.google.com> References: <168904147563.2908673.18054267804278861545.stgit@mhiramat.roam.corp.google.com> User-Agent: StGit/0.19 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org From: Masami Hiramatsu (Google) This reverts commit 2e9906f84fc7c99388bb7123ade167250d50f1c0. It was turned out that commit 2e9906f84fc7 ("tracing: Add "(fault)" name injection to kernel probes") did not work correctly and probe events still show just '(fault)' (instead of '"(fault)"'). Also, current '(fault)' is more explicit that it faulted. This also moves FAULT_STRING macro to trace.h so that synthetic event can keep using it, and uses it in trace_probe.c too. Link: https://lore.kernel.org/all/20230706230642.3793a593@rorschach.local.home/ Cc: stable@vger.kernel.org Cc: Andrew Morton Cc: Tom Zanussi Signed-off-by: Masami Hiramatsu (Google) --- Changes in v3: - Move FAULT_STRING macro to trace.h so that synthetic event can keep using it. - Use FAULT_STRING in trace_probe.c. --- kernel/trace/trace.h | 2 ++ kernel/trace/trace_probe.c | 2 +- kernel/trace/trace_probe_kernel.h | 31 ++++++------------------------- 3 files changed, 9 insertions(+), 26 deletions(-) diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 79bdefe9261b..eee1f3ca4749 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -113,6 +113,8 @@ enum trace_type { #define MEM_FAIL(condition, fmt, ...) \ DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__) +#define FAULT_STRING "(fault)" + #define HIST_STACKTRACE_DEPTH 16 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long)) #define HIST_STACKTRACE_SKIP 5 diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 2d2616678295..591399ddcee5 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -65,7 +65,7 @@ int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, void *data, void *ent) int len = *(u32 *)data >> 16; if (!len) - trace_seq_puts(s, "(fault)"); + trace_seq_puts(s, FAULT_STRING); else trace_seq_printf(s, "\"%s\"", (const char *)get_loc_data(data, ent)); diff --git a/kernel/trace/trace_probe_kernel.h b/kernel/trace/trace_probe_kernel.h index c4e1d4c03a85..6deae2ce34f8 100644 --- a/kernel/trace/trace_probe_kernel.h +++ b/kernel/trace/trace_probe_kernel.h @@ -2,8 +2,6 @@ #ifndef __TRACE_PROBE_KERNEL_H_ #define __TRACE_PROBE_KERNEL_H_ -#define FAULT_STRING "(fault)" - /* * This depends on trace_probe.h, but can not include it due to * the way trace_probe_tmpl.h is used by trace_kprobe.c and trace_eprobe.c. @@ -15,16 +13,8 @@ static nokprobe_inline int fetch_store_strlen_user(unsigned long addr) { const void __user *uaddr = (__force const void __user *)addr; - int ret; - ret = strnlen_user_nofault(uaddr, MAX_STRING_SIZE); - /* - * strnlen_user_nofault returns zero on fault, insert the - * FAULT_STRING when that occurs. - */ - if (ret <= 0) - return strlen(FAULT_STRING) + 1; - return ret; + return strnlen_user_nofault(uaddr, MAX_STRING_SIZE); } /* Return the length of string -- including null terminal byte */ @@ -44,18 +34,7 @@ fetch_store_strlen(unsigned long addr) len++; } while (c && ret == 0 && len < MAX_STRING_SIZE); - /* For faults, return enough to hold the FAULT_STRING */ - return (ret < 0) ? strlen(FAULT_STRING) + 1 : len; -} - -static nokprobe_inline void set_data_loc(int ret, void *dest, void *__dest, void *base, int len) -{ - if (ret >= 0) { - *(u32 *)dest = make_data_loc(ret, __dest - base); - } else { - strscpy(__dest, FAULT_STRING, len); - ret = strlen(__dest) + 1; - } + return (ret < 0) ? ret : len; } /* @@ -76,7 +55,8 @@ fetch_store_string_user(unsigned long addr, void *dest, void *base) __dest = get_loc_data(dest, base); ret = strncpy_from_user_nofault(__dest, uaddr, maxlen); - set_data_loc(ret, dest, __dest, base, maxlen); + if (ret >= 0) + *(u32 *)dest = make_data_loc(ret, __dest - base); return ret; } @@ -107,7 +87,8 @@ fetch_store_string(unsigned long addr, void *dest, void *base) * probing. */ ret = strncpy_from_kernel_nofault(__dest, (void *)addr, maxlen); - set_data_loc(ret, dest, __dest, base, maxlen); + if (ret >= 0) + *(u32 *)dest = make_data_loc(ret, __dest - base); return ret; }