Commit 95c36561 authored Feb 26, 2016 by Wang Nan Committed by Arnaldo Carvalho de Melo Mar 03, 2016

perf record: Ensure return non-zero rc when mmap fail



perf_evlist__mmap_ex() can fail without setting errno (for example, fail
in condition checking. In this case all syscall is success).

If this happen, record__open() incorrectly returns 0. Force setting rc
is a quick way to avoid this problem, or we have to follow all possible
code path in perf_evlist__mmap_ex() to make sure there's at least one
system call before returning an error.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1456479154-136027-30-git-send-email-wangnan0@huawei.com


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

parent e1ab48ba

tools/perf/builtin-record.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -324,7 +324,10 @@ static int record__open(struct record *rec)
		} else {
		pr_err("failed to mmap with %d (%s)\n", errno,
		strerror_r(errno, msg, sizeof(msg)));
		if (errno)
		rc = -errno;
		else
		rc = -EINVAL;
		}
		goto out;
		}