The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 49e67dd17649b60b4d54966e18ec9c80198227f0 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@xxxxxxxxxx>
Date: Wed, 17 May 2017 17:29:09 +0200
Subject: [PATCH] of: fdt: add missing allocation-failure check
The memory allocator passed to __unflatten_device_tree() (e.g. a wrapped
kzalloc) can fail so add the missing sanity check to avoid dereferencing
a NULL pointer.
Fixes: fe14042358fa ("of/flattree: Refactor unflatten_device_tree and add fdt_unflatten_tree")
Cc: stable <stable@xxxxxxxxxxxxxxx> # 2.6.38
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index a0972219ccfc..0373ae49d24d 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -507,6 +507,9 @@ void *__unflatten_device_tree(const void *blob,
/* Allocate memory for the expanded device tree */
mem = dt_alloc(size + 4, __alignof__(struct device_node));
+ if (!mem)
+ return NULL;
+
memset(mem, 0, size);
*(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);