This is a note to let you know that I've just added the patch titled
tracing: Fix NULL pointer dereference in start_creating
to the 5.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tracing-fix-null-pointer-dereference-in-start_creating.patch
and it can be found in the queue-5.13 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From ff41c28c4b54052942180d8b3f49e75f1445135a Mon Sep 17 00:00:00 2001
From: Kamal Agrawal <kamaagra@xxxxxxxxxxxxxx>
Date: Fri, 30 Jul 2021 18:53:06 +0530
Subject: tracing: Fix NULL pointer dereference in start_creating
From: Kamal Agrawal <kamaagra@xxxxxxxxxxxxxx>
commit ff41c28c4b54052942180d8b3f49e75f1445135a upstream.
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
Link: https://lkml.kernel.org/r/1627651386-21315-1-git-send-email-kamaagra@xxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 4114fbfd02f1 ("tracing: Enable creating new instance early boot")
Signed-off-by: Kamal Agrawal <kamaagra@xxxxxxxxxxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/trace/trace.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -9006,8 +9006,10 @@ static int trace_array_create_dir(struct
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);
Patches currently in stable-queue which might be from kamaagra@xxxxxxxxxxxxxx are
queue-5.13/tracing-fix-null-pointer-dereference-in-start_creating.patch
