From: Song Liu songliubraving@fb.com
commit 29c77550eef31b0d72a45b49eeab03b8963264e8 upstream.
When perf.data is not written cleanly, we would like to process existing data as much as possible (please see f_header.data.size == 0 condition in perf_session__read_header). However, perf.data with partial data may crash perf. Specifically, we see crash in 'perf script' for NULL session->header.env.arch.
Fix this by checking session->header.env.arch before using it to determine native_arch. Also split the if condition so it is easier to read.
Committer notes:
If it is a pipe, we already assume is a native arch, so no need to check session->header.env.arch.
Signed-off-by: Song Liu songliubraving@fb.com Cc: Peter Zijlstra peterz@infradead.org Cc: kernel-team@fb.com Cc: stable@vger.kernel.org Link: http://lore.kernel.org/lkml/20211004053238.514936-1-songliubraving@fb.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- tools/perf/builtin-script.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)
--- a/tools/perf/builtin-script.c +++ b/tools/perf/builtin-script.c @@ -4024,11 +4024,15 @@ script_found: goto out_delete;
uname(&uts); - if (data.is_pipe || /* assume pipe_mode indicates native_arch */ - !strcmp(uts.machine, session->header.env.arch) || - (!strcmp(uts.machine, "x86_64") && - !strcmp(session->header.env.arch, "i386"))) + if (data.is_pipe) { /* Assume pipe_mode indicates native_arch */ native_arch = true; + } else if (session->header.env.arch) { + if (!strcmp(uts.machine, session->header.env.arch)) + native_arch = true; + else if (!strcmp(uts.machine, "x86_64") && + !strcmp(session->header.env.arch, "i386")) + native_arch = true; + }
script.session = session; script__setup_sample_type(&script);