From patchwork Fri Jul 7 13:41:21 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: 13304901 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 347CEC0015E for ; Fri, 7 Jul 2023 13:41:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232199AbjGGNlt (ORCPT ); Fri, 7 Jul 2023 09:41:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54692 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232478AbjGGNli (ORCPT ); Fri, 7 Jul 2023 09:41:38 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D3F0926AC; Fri, 7 Jul 2023 06:41:25 -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 60959619A0; Fri, 7 Jul 2023 13:41:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9CBE4C433C8; Fri, 7 Jul 2023 13:41:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1688737284; bh=jw6d8p0evmmLgL+3c21Ikyeph2z5FEfOBl7kFpuv2U0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eLHO4WNRDixHbTt5uvtKqOR4/ipQeshtWMJ7pgUkiX8ZHGrvM8BCKpJJanHs/OC52 JzUXKgeG9i22eWxAeg29BHKM4kAiGEr9kGDIvx0+AqQUwvAaWZN5Bubq1jRdneOAaz Y577uxPLpreJWRmERnt/k8l9IEDn8K41ZQZ0OcT0Z1Z5FTj+dIqjb5DxG3r543+zxl 4UXSvoSUeIBOHj/Fa31UdsECn/GCGQOF+G6iNG2FF/Kuv8kUhRU9lWeXAC52l8ugs6 +tKKiBw6vFqoZJA8HncCjoBkd1V8r81qAIPmRYhD4yDAEzgX1F7jft35M5lIruCUoR LTYVlhYrjUQ4g== From: "Masami Hiramatsu (Google)" To: Steven Rostedt Cc: Dan Carpenter , linux-trace-kernel@vger.kernel.org, LKML , Masami Hiramatsu Subject: [PATCH v2 4/4] tracing/probes: Fix to record 0-length data_loc in fetch_store_string*() if fails Date: Fri, 7 Jul 2023 22:41:21 +0900 Message-ID: <168873728100.2687993.818241227929882555.stgit@mhiramat.roam.corp.google.com> X-Mailer: git-send-email 2.41.0.255.g8b1d071c50-goog In-Reply-To: <168873724526.2687993.15242662075324919195.stgit@mhiramat.roam.corp.google.com> References: <168873724526.2687993.15242662075324919195.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) Fix to record 0-length data to data_loc in fetch_store_string*() if it fails to get the string data. Currently those expect that the data_loc is updated by store_trace_args() if it returns the error code. However, that does not work correctly if the argument is an array of strings. In that case, store_trace_args() only clears the first entry of the array (which may have no error) and leaves other entries. So it should be cleared by fetch_store_string*() itself. Also, 'dyndata' and 'maxlen' in store_trace_args() should be updated only if it is used (ret > 0 and argument is a dynamic data.) Fixes: 40b53b771806 ("tracing: probeevent: Add array type support") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) --- kernel/trace/trace_probe_kernel.h | 6 ++---- kernel/trace/trace_probe_tmpl.h | 4 +--- kernel/trace/trace_uprobe.c | 3 ++- 3 files changed, 5 insertions(+), 8 deletions(-) diff --git a/kernel/trace/trace_probe_kernel.h b/kernel/trace/trace_probe_kernel.h index 6deae2ce34f8..37d5696ed768 100644 --- a/kernel/trace/trace_probe_kernel.h +++ b/kernel/trace/trace_probe_kernel.h @@ -55,8 +55,7 @@ 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); - if (ret >= 0) - *(u32 *)dest = make_data_loc(ret, __dest - base); + *(u32 *)dest = make_data_loc((ret >= 0) ? ret : 0, __dest - base); return ret; } @@ -87,8 +86,7 @@ fetch_store_string(unsigned long addr, void *dest, void *base) * probing. */ ret = strncpy_from_kernel_nofault(__dest, (void *)addr, maxlen); - if (ret >= 0) - *(u32 *)dest = make_data_loc(ret, __dest - base); + *(u32 *)dest = make_data_loc((ret >= 0) ? ret : 0, __dest - base); return ret; } diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h index ed9d57c6b041..bbad0503f166 100644 --- a/kernel/trace/trace_probe_tmpl.h +++ b/kernel/trace/trace_probe_tmpl.h @@ -267,9 +267,7 @@ store_trace_args(void *data, struct trace_probe *tp, void *rec, 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 { + if (unlikely(ret > 0 && arg->dynamic)) { dyndata += ret; maxlen -= ret; } diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 8b92e34ff0c8..7b47e9a2c010 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -170,7 +170,8 @@ fetch_store_string(unsigned long addr, void *dest, void *base) */ ret++; *(u32 *)dest = make_data_loc(ret, (void *)dst - base); - } + } else + *(u32 *)dest = make_data_loc(0, (void *)dst - base); return ret; }