| Message ID | 1627651386-21315-1-git-send-email-kamaagra@codeaurora.org (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | tracing: Fix NULL pointer dereference in start_creating | expand |
On Fri, 30 Jul 2021 18:53:06 +0530 Kamal Agrawal <kamaagra@codeaurora.org> wrote: > The event_trace_add_tracer() can fail. In this case, it leads to a crash > in start_creating with below call stack. Handle the error scenario > properly in trace_array_create_dir. > > Call trace: > down_write+0x7c/0x204 > start_creating.25017+0x6c/0x194 > tracefs_create_file+0xc4/0x2b4 > init_tracer_tracefs+0x5c/0x940 > trace_array_create_dir+0x58/0xb4 > trace_array_create+0x1bc/0x2b8 > trace_array_get_by_name+0xdc/0x18c > > Fixes: 4114fbfd Thanks, I'll queue this up. -- Steve > Signed-off-by: Kamal Agrawal <kamaagra@codeaurora.org> > --- > kernel/trace/trace.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > index c59dd35..33899a7 100644 > --- a/kernel/trace/trace.c > +++ b/kernel/trace/trace.c > @@ -9135,8 +9135,10 @@ static int trace_array_create_dir(struct trace_array *tr) > return -EINVAL; > > ret = event_trace_add_tracer(tr->dir, tr); > - if (ret) > + if (ret) { > tracefs_remove(tr->dir); > + return ret; > + } > > init_tracer_tracefs(tr, tr->dir); > __update_tracer_options(tr);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index c59dd35..33899a7 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -9135,8 +9135,10 @@ static int trace_array_create_dir(struct trace_array *tr) return -EINVAL; ret = event_trace_add_tracer(tr->dir, tr); - if (ret) + if (ret) { tracefs_remove(tr->dir); + return ret; + } init_tracer_tracefs(tr, tr->dir); __update_tracer_options(tr);
The event_trace_add_tracer() can fail. In this case, it leads to a crash in start_creating with below call stack. Handle the error scenario properly in trace_array_create_dir. Call trace: down_write+0x7c/0x204 start_creating.25017+0x6c/0x194 tracefs_create_file+0xc4/0x2b4 init_tracer_tracefs+0x5c/0x940 trace_array_create_dir+0x58/0xb4 trace_array_create+0x1bc/0x2b8 trace_array_get_by_name+0xdc/0x18c Fixes: 4114fbfd Signed-off-by: Kamal Agrawal <kamaagra@codeaurora.org> --- kernel/trace/trace.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)