linux-kernel - Re: [PATCH 31/32] tools lib traceevent: Support function __get_dynamic_array

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <55E0FCF2.6040403@plumgrid.com>
Date:	Fri, 28 Aug 2015 17:29:38 -0700
From:	Alexei Starovoitov <ast@...mgrid.com>
To:	Wang Nan <wangnan0@...wei.com>, acme@...hat.com
Cc:	brendan.d.gregg@...il.com, daniel@...earbox.net, dsahern@...il.com,
	hekuang@...wei.com, jolsa@...nel.org, xiakaixu@...wei.com,
	masami.hiramatsu.pt@...achi.com, namhyung@...nel.org,
	a.p.zijlstra@...llo.nl, lizefan@...wei.com, pi3orama@....com,
	linux-kernel@...r.kernel.org,
	Arnaldo Carvalho de Melo <acme@...nel.org>,
	Ingo Molnar <mingo@...hat.com>,
	Steven Rostedt <rostedt@...dmis.org>
Subject: Re: [PATCH 31/32] tools lib traceevent: Support function
 __get_dynamic_array_len

On 8/28/15 12:06 AM, Wang Nan wrote:
> From: He Kuang<hekuang@...wei.com>
>
> Support helper function __get_dynamic_array_len() in libtraceevent,
> this function is used accompany with __print_array() or __print_hex(),
> but currently it is not an available function in the function list of
> process_function().
>
> The total allocated length of the dynamic array is embedded in the top
> half of __data_loc_##item field. This patch adds new arg type
> PRINT_DYNAMIC_ARRAY_LEN to return the length to eval_num_arg(),
>
> Signed-off-by: He Kuang<hekuang@...wei.com>
> Acked-by: Namhyung Kim<namhyung@...nel.org>

Tested-by: Alexei Starovoitov <ast@...mgrid.com>

this patch fixes the perf crash:
   Warning: [bpf:bpf_output_data] function __get_dynamic_array_len not 
defined
   Warning: Error: expected type 5 but read 0
*** glibc detected *** perf_4.2.0: double free or corruption (fasttop): 
0x00000000032caf20 ***
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x7ec96)[0x7f0d5d2d3c96]

it's not strictly necessary until patch 32 lands, but I think it's
a good fix regardless.
Steven, could you take it into your tree?

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/