From dd520da215e1f8558206ddade1f55b239730bd4f Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Tue, 26 Dec 2017 20:07:34 -0500 Subject: [PATCH] tracing: Fix possible double free on failure of allocating trace buffer commit 4397f04575c44e1440ec2e49b6302785c95fd2f8 upstream. Jing Xia and Chunyan Zhang reported that on failing to allocate part of the tracing buffer, memory is freed, but the pointers that point to them are not initialized back to NULL, and later paths may try to free the freed memory again. Jing and Chunyan fixed one of the locations that does this, but missed a spot. Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com Fixes: 737223fbca3b1 ("tracing: Consolidate buffer allocation code") Reported-by: Jing Xia Reported-by: Chunyan Zhang Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Ben Hutchings --- kernel/trace/trace.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 8cbcd8995271..36ac29ef278f 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -6220,6 +6220,7 @@ allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size buf->data = alloc_percpu(struct trace_array_cpu); if (!buf->data) { ring_buffer_free(buf->buffer); + buf->buffer = NULL; return -ENOMEM; }