From: Johan Hovold <johan@kernel.org>
Date: Wed, 17 May 2017 15:29:09 +0000 (+0200)
Subject: of: fdt: add missing allocation-failure check
X-Git-Tag: v5.15~11265^2
X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=49e67dd17649b60b4d54966e18ec9c80198227f0;p=mirror_ubuntu-kernels.git

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@vger.kernel.org>     # 2.6.38
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
---

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);