From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 E8438225D7; Thu, 27 Mar 2025 07:16:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743059801; cv=none; b=LrdNavx8RfSkjBt1i8xUuwEp5BT8ttNqPxWYFY/5qgz8mX4eYpBjy3KSkUxC4yU65xKAClHLPCN1yZ2+ohbjimPYXkUqnKbuaVSsM66gvA+h0JxdB3UrAuY168U2Ol/ejY0t2QKytiQ52GsgojXef4YtRrkS6WL1xQaKbXE+IK0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743059801; c=relaxed/simple; bh=zhHvo/ZDWQ4l9fAWfTKydbGpXbrK382IHtHkv8djzso=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=sHwyMXCWcPruIQ4+ajGEzjxHNdf41TsV1PRpV4nQQe1Fwez5NeKuxgf/HnMrnlqC9wCoIG/XXCBMvT5nTrZaNGaJNji0mNuRIxhKjg1LL1vDTkUo+aTNhsztwfhn7z052QrHw2qOQmm3cDCjJne/qPyqEBWQnP17iTDvV0wqW7k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JMY1eFDG; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="JMY1eFDG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EF28BC4CEE4; Thu, 27 Mar 2025 07:16:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743059800; bh=zhHvo/ZDWQ4l9fAWfTKydbGpXbrK382IHtHkv8djzso=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=JMY1eFDGsR6/qHesdAg+bEH36xpcXqyVhojK6xUUy/weCfVN38VQW5WoOrJgZ6SKN prjkSvgEnIRlKuQM114Vnh3NlTPa4m7V2aWqb2jN85/Ia1eNUrKMDQVwzbW87nI7CP ynEFWaIPRJH40ZJCkxA4mGjt3ZqnieM2CIxgzVmNymMFTk07asw0p+ZYE6psYibJH7 kTS/nkgBoDGu34rIG87cnx6bjeF319p2l/IX/kYshTjKU6X5ITYbqtBHct1jlqNOKF FUD/YZ5HBEAtrMSnzYTMaFPznx+uKZH4VYmVJlzClusUGyPed15IKIPBgkakzjQAIW 1/qzIyjGZ85Mw== Date: Thu, 27 Mar 2025 00:16:38 -0700 From: Namhyung Kim To: Howard Chu Cc: acme@kernel.org, mingo@redhat.com, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org, irogers@google.com, adrian.hunter@intel.com, peterz@infradead.org, kan.liang@linux.intel.com, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] perf trace: Fix possible insufficient allocation of argument formats Message-ID: References: <20250326200540.1843856-1-howardchu95@gmail.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20250326200540.1843856-1-howardchu95@gmail.com> Hello, On Wed, Mar 26, 2025 at 01:05:40PM -0700, Howard Chu wrote: > Changes in v2: > * Simplify the code (written by Namhyung) Please move this below "---" after S-o-b tags so that it can be ignored when applying. > > In my previous fix of runtime error(Link: > https://lore.kernel.org/linux-perf-users/20250122025519.361873-1-howardchu95@gmail.com/), > I made a mistake of decrementing one unconditionally, regardless of > whether an extra 'syscall_nr' or 'nr' field was present in > libtraceevent's tp_format. This may cause perf trace to allocate one > fewer arg_fmt entry than needed for the accurate representation of syscall > arguments. > > This patch corrects the mistake by checking the presence of'syscall_nr' or > 'nr', and adjusting the length of arg_fmt[] accordingly. > > Signed-off-by: Howard Chu > Suggested-by: Namhyung Kim Also please add the Fixes tag. Thanks, Namhyung > --- > tools/perf/builtin-trace.c | 16 +++++----------- > 1 file changed, 5 insertions(+), 11 deletions(-) > > diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c > index a102748bd0c9..439e152186da 100644 > --- a/tools/perf/builtin-trace.c > +++ b/tools/perf/builtin-trace.c > @@ -2022,9 +2022,6 @@ static int syscall__alloc_arg_fmts(struct syscall *sc, int nr_args) > { > int idx; > > - if (nr_args == RAW_SYSCALL_ARGS_NUM && sc->fmt && sc->fmt->nr_args != 0) > - nr_args = sc->fmt->nr_args; > - > sc->arg_fmt = calloc(nr_args, sizeof(*sc->arg_fmt)); > if (sc->arg_fmt == NULL) > return -1; > @@ -2034,7 +2031,6 @@ static int syscall__alloc_arg_fmts(struct syscall *sc, int nr_args) > sc->arg_fmt[idx] = sc->fmt->arg[idx]; > } > > - sc->nr_args = nr_args; > return 0; > } > > @@ -2176,14 +2172,9 @@ static int syscall__read_info(struct syscall *sc, struct trace *trace) > return err; > } > > - /* > - * The tracepoint format contains __syscall_nr field, so it's one more > - * than the actual number of syscall arguments. > - */ > - if (syscall__alloc_arg_fmts(sc, sc->tp_format->format.nr_fields - 1)) > - return -ENOMEM; > - > sc->args = sc->tp_format->format.fields; > + sc->nr_args = sc->tp_format->format.nr_fields; > + > /* > * We need to check and discard the first variable '__syscall_nr' > * or 'nr' that mean the syscall number. It is needless here. > @@ -2194,6 +2185,9 @@ static int syscall__read_info(struct syscall *sc, struct trace *trace) > --sc->nr_args; > } > > + if (syscall__alloc_arg_fmts(sc, sc->nr_args)) > + return -ENOMEM; > + > sc->is_exit = !strcmp(name, "exit_group") || !strcmp(name, "exit"); > sc->is_open = !strcmp(name, "open") || !strcmp(name, "openat"); > > -- > 2.45.2 >