Re: [PATCH 1/2] perf inject: Fix segfault due to close without open

From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>,
	linux-kernel@vger.kernel.org,
	Riccardo Mancini <rickyman7@gmail.com>,
	Namhyung Kim <namhyung@kernel.org>
Subject: Re: [PATCH 1/2] perf inject: Fix segfault due to close without open
Date: Mon, 13 Dec 2021 10:11:59 -0300	[thread overview]
Message-ID: <YbdGn89u/HXXvfwo@kernel.org> (raw)
In-Reply-To: <20211213084829.114772-2-adrian.hunter@intel.com>

Em Mon, Dec 13, 2021 at 10:48:28AM +0200, Adrian Hunter escreveu:
> The fixed commit attempts to close inject.output even if it was never
> opened e.g.
> 
>  $ perf record uname
>  Linux
>  [ perf record: Woken up 1 times to write data ]
>  [ perf record: Captured and wrote 0.002 MB perf.data (7 samples) ]
>  $ perf inject -i perf.data --vm-time-correlation=dry-run
>  Segmentation fault (core dumped)
>  $ gdb --quiet perf
>  Reading symbols from perf...
>  (gdb) r inject -i perf.data --vm-time-correlation=dry-run
>  Starting program: /home/ahunter/bin/perf inject -i perf.data --vm-time-correlation=dry-run
>  [Thread debugging using libthread_db enabled]
>  Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".

Thanks, applied.

- Arnaldo

>  Program received signal SIGSEGV, Segmentation fault.
>  0x00007eff8afeef5b in _IO_new_fclose (fp=0x0) at iofclose.c:48
>  48      iofclose.c: No such file or directory.
>  (gdb) bt
>  #0  0x00007eff8afeef5b in _IO_new_fclose (fp=0x0) at iofclose.c:48
>  #1  0x0000557fc7b74f92 in perf_data__close (data=data@entry=0x7ffcdafa6578) at util/data.c:376
>  #2  0x0000557fc7a6b807 in cmd_inject (argc=<optimized out>, argv=<optimized out>) at builtin-inject.c:1085
>  #3  0x0000557fc7ac4783 in run_builtin (p=0x557fc8074878 <commands+600>, argc=4, argv=0x7ffcdafb6a60) at perf.c:313
>  #4  0x0000557fc7a25d5c in handle_internal_command (argv=<optimized out>, argc=<optimized out>) at perf.c:365
>  #5  run_argv (argcp=<optimized out>, argv=<optimized out>) at perf.c:409
>  #6  main (argc=4, argv=0x7ffcdafb6a60) at perf.c:539
>  (gdb)
> 
> Fixes: 02e6246f5364d ("perf inject: Close inject.output on exit")
> Cc: stable@vger.kernel.org
> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
> ---
>  tools/perf/builtin-inject.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c
> index b9d6306cc14e..af70f1c72052 100644
> --- a/tools/perf/builtin-inject.c
> +++ b/tools/perf/builtin-inject.c
> @@ -1078,7 +1078,8 @@ int cmd_inject(int argc, const char **argv)
>  	zstd_fini(&(inject.session->zstd_data));
>  	perf_session__delete(inject.session);
>  out_close_output:
> -	perf_data__close(&inject.output);
> +	if (!inject.in_place_update)
> +		perf_data__close(&inject.output);
>  	free(inject.itrace_synth_opts.vm_tm_corr_args);
>  	return ret;
>  }
> -- 
> 2.25.1

-- 

- Arnaldo