Commit 0216234c authored Sep 12, 2019 by Jiri Olsa Committed by Arnaldo Carvalho de Melo Sep 20, 2019

perf tools: Fix segfault in cpu_cache_level__read()



We release wrong pointer on error path in cpu_cache_level__read
function, leading to segfault:

  (gdb) r record ls
  Starting program: /root/perf/tools/perf/perf record ls
  ...
  [ perf record: Woken up 1 times to write data ]
  double free or corruption (out)

  Thread 1 "perf" received signal SIGABRT, Aborted.
  0x00007ffff7463798 in raise () from /lib64/power9/libc.so.6
  (gdb) bt
  #0  0x00007ffff7463798 in raise () from /lib64/power9/libc.so.6
  #1  0x00007ffff7443bac in abort () from /lib64/power9/libc.so.6
  #2  0x00007ffff74af8bc in __libc_message () from /lib64/power9/libc.so.6
  #3  0x00007ffff74b92b8 in malloc_printerr () from /lib64/power9/libc.so.6
  #4  0x00007ffff74bb874 in _int_free () from /lib64/power9/libc.so.6
  #5  0x0000000010271260 in __zfree (ptr=0x7fffffffa0b0) at ../../lib/zalloc..
  #6  0x0000000010139340 in cpu_cache_level__read (cache=0x7fffffffa090, cac..
  #7  0x0000000010143c90 in build_caches (cntp=0x7fffffffa118, size=<optimiz..
  ...

Releasing the proper pointer.

Fixes: 720e98b5 ("perf tools: Add perf data cache feature")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org: # v4.6+
Link: http://lore.kernel.org/lkml/20190912105235.10689-1-jolsa@kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 40f1c039

tools/perf/util/header.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1073,7 +1073,7 @@ static int cpu_cache_level__read(struct cpu_cache_level *cache, u32 cpu, u16 lev

		scnprintf(file, PATH_MAX, "%s/shared_cpu_list", path);
		if (sysfs__read_str(file, &cache->map, &len)) {
		zfree(&cache->map);
		zfree(&cache->size);
		zfree(&cache->type);
		return -1;
		}

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