Subject: Re: [PATCH 07/16] perf: top: fix heap-use-after-free issue

From: Jiri Olsa <[email-masked]>
Date: Mon, 18 Mar 2019 11:08:05 +0100

On Sat, Mar 16, 2019 at 04:05:47PM +0800, Changbin Du wrote:
> The evlist should be destroyed before the perf session.
> 
> =================================================================
> ==27350==ERROR: AddressSanitizer: heap-use-after-free on address 0x62b000002e38 at pc 0x5611da276999 bp 0x7ffce8f1d1a0 sp 0x7ffce8f1d190
> WRITE of size 8 at 0x62b000002e38 thread T0
>     #0 0x5611da276998 in __list_del /home/work/linux/tools/include/linux/list.h:89
>     #1 0x5611da276d4a in __list_del_entry /home/work/linux/tools/include/linux/list.h:102
>     #2 0x5611da276e77 in list_del_init /home/work/linux/tools/include/linux/list.h:145
>     #3 0x5611da2781cd in thread__put util/thread.c:130

ah, because thread is on the machine's list.. which is inside session
looks like we could use refference counts in machine in future

thanks,
jirka

>     #4 0x5611da2cc0a8 in __thread__zput util/thread.h:68
>     #5 0x5611da2d2dcb in hist_entry__delete util/hist.c:1148
>     #6 0x5611da2cdf91 in hists__delete_entry util/hist.c:337
>     #7 0x5611da2ce19e in hists__delete_entries util/hist.c:365
>     #8 0x5611da2db2ab in hists__delete_all_entries util/hist.c:2639
>     #9 0x5611da2db325 in hists_evsel__exit util/hist.c:2651
>     #10 0x5611da1c5352 in perf_evsel__exit util/evsel.c:1304
>     #11 0x5611da1c5390 in perf_evsel__delete util/evsel.c:1309
>     #12 0x5611da1b35f0 in perf_evlist__purge util/evlist.c:124
>     #13 0x5611da1b38e2 in perf_evlist__delete util/evlist.c:148
>     #14 0x5611da069781 in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1645
>     #15 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
>     #16 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
>     #17 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
>     #18 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520
>     #19 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)
>     #20 0x5611d9ff35c9 in _start (/home/work/linux/tools/perf/perf+0x3e95c9)
> 
> 0x62b000002e38 is located 11320 bytes inside of 27448-byte region [0x62b000000200,0x62b000006d38)
> freed by thread T0 here:
>     #0 0x7fdccb04ab70 in free (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedb70)
>     #1 0x5611da260df4 in perf_session__delete util/session.c:201
>     #2 0x5611da063de5 in __cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1300
>     #3 0x5611da06973c in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1642
>     #4 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
>     #5 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
>     #6 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
>     #7 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520
>     #8 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)
> 
> previously allocated by thread T0 here:
>     #0 0x7fdccb04b138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138)
>     #1 0x5611da26010c in zalloc util/util.h:23
>     #2 0x5611da260824 in perf_session__new util/session.c:118
>     #3 0x5611da0633a6 in __cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1192
>     #4 0x5611da06973c in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1642
>     #5 0x5611da17d038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
>     #6 0x5611da17d577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
>     #7 0x5611da17d97b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
>     #8 0x5611da17e0e9 in main /home/changbin/work/linux/tools/perf/perf.c:520
>     #9 0x7fdcc970f09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)
> 
> SUMMARY: AddressSanitizer: heap-use-after-free /home/work/linux/tools/include/linux/list.h:89 in __list_del
> Shadow bytes around the buggy address:
>   0x0c567fff8570: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
>   0x0c567fff8580: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
>   0x0c567fff8590: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
>   0x0c567fff85a0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
>   0x0c567fff85b0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
> =>0x0c567fff85c0: fd fd fd fd fd fd fd[fd]fd fd fd fd fd fd fd fd
>   0x0c567fff85d0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
>   0x0c567fff85e0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
>   0x0c567fff85f0: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
>   0x0c567fff8600: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
>   0x0c567fff8610: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
> Shadow byte legend (one shadow byte represents 8 application bytes):
>   Addressable:           00
>   Partially addressable: 01 02 03 04 05 06 07
>   Heap left redzone:       fa
>   Freed heap region:       fd
>   Stack left redzone:      f1
>   Stack mid redzone:       f2
>   Stack right redzone:     f3
>   Stack after return:      f5
>   Stack use after scope:   f8
>   Global redzone:          f9
>   Global init order:       f6
>   Poisoned by user:        f7
>   Container overflow:      fc
>   Array cookie:            ac
>   Intra object redzone:    bb
>   ASan internal:           fe
>   Left alloca redzone:     ca
>   Right alloca redzone:    cb
> ==27350==ABORTING
> 
> Signed-off-by: Changbin Du <[email-masked]>
> ---
>  tools/perf/builtin-top.c | 42 ++++++++++++++++++----------------------
>  1 file changed, 19 insertions(+), 23 deletions(-)
> 
> diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
> index 231a90daa958..614f278235fa 100644
> --- a/tools/perf/builtin-top.c
> +++ b/tools/perf/builtin-top.c
> @@ -1189,23 +1189,19 @@ static int __cmd_top(struct perf_top *top)
>  	pthread_t thread, thread_process;
>  	int ret;
>  
> -	top->session = perf_session__new(NULL, false, NULL);
> -	if (top->session == NULL)
> -		return -1;
> -
>  	if (!top->annotation_opts.objdump_path) {
>  		ret = perf_env__lookup_objdump(&top->session->header.env,
>  					       &top->annotation_opts.objdump_path);
>  		if (ret)
> -			goto out_delete;
> +			return ret;
>  	}
>  
>  	ret = callchain_param__setup_sample_type(&callchain_param);
>  	if (ret)
> -		goto out_delete;
> +		return ret;
>  
>  	if (perf_session__register_idle_thread(top->session) < 0)
> -		goto out_delete;
> +		return ret;
>  
>  	if (top->nr_threads_synthesize > 1)
>  		perf_set_multithreaded();
> @@ -1227,13 +1223,18 @@ static int __cmd_top(struct perf_top *top)
>  
>  	if (perf_hpp_list.socket) {
>  		ret = perf_env__read_cpu_topology_map(&perf_env);
> -		if (ret < 0)
> -			goto out_err_cpu_topo;
> +		if (ret < 0) {
> +			char errbuf[BUFSIZ];
> +			const char *err = str_error_r(-ret, errbuf, sizeof(errbuf));
> +
> +			ui__error("Could not read the CPU topology map: %s\n", err);
> +			return ret;
> +		}
>  	}
>  
>  	ret = perf_top__start_counters(top);
>  	if (ret)
> -		goto out_delete;
> +		return ret;
>  
>  	top->session->evlist = top->evlist;
>  	perf_session__set_id_hdr_size(top->session);
> @@ -1252,7 +1253,7 @@ static int __cmd_top(struct perf_top *top)
>  	ret = -1;
>  	if (pthread_create(&thread_process, NULL, process_thread, top)) {
>  		ui__error("Could not create process thread.\n");
> -		goto out_delete;
> +		return ret;
>  	}
>  
>  	if (pthread_create(&thread, NULL, (use_browser > 0 ? display_thread_tui :
> @@ -1296,19 +1297,7 @@ static int __cmd_top(struct perf_top *top)
>  out_join_thread:
>  	pthread_cond_signal(&top->qe.cond);
>  	pthread_join(thread_process, NULL);
> -out_delete:
> -	perf_session__delete(top->session);
> -	top->session = NULL;
> -
>  	return ret;
> -
> -out_err_cpu_topo: {
> -	char errbuf[BUFSIZ];
> -	const char *err = str_error_r(-ret, errbuf, sizeof(errbuf));
> -
> -	ui__error("Could not read the CPU topology map: %s\n", err);
> -	goto out_delete;
> -}
>  }
>  
>  static int
> @@ -1639,10 +1628,17 @@ int cmd_top(int argc, const char **argv)
>  		signal(SIGWINCH, winch_sig);
>  	}
>  
> +	top.session = perf_session__new(NULL, false, NULL);
> +	if (top.session == NULL) {
> +		status = -1;
> +		goto out_delete_evlist;
> +	}
> +
>  	status = __cmd_top(&top);
>  
>  out_delete_evlist:
>  	perf_evlist__delete(top.evlist);
> +	perf_session__delete(top.session);
>  
>  	return status;
>  }
> -- 
> 2.19.1
>