nvmem: sunxi: Check for memory allocation failure

The sunxi_sid driver doesn't check for kmalloc return status before
derefencing the returned pointer, which could lead to a NULL pointer
dereference if kmalloc failed. Check for its return code to make sure it
deosn't happen.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/nvmem/sunxi_sid.c b/drivers/nvmem/sunxi_sid.c
index 14777dd..cfa3b85 100644 (file)
--- a/drivers/nvmem/sunxi_sid.c
+++ b/drivers/nvmem/sunxi_sid.c
@@ -103,7 +103,7 @@ static int sunxi_sid_probe(struct platform_device *pdev)
        struct nvmem_device *nvmem;
        struct regmap *regmap;
        struct sunxi_sid *sid;
-       int i, size;
+       int ret, i, size;
        char *randomness;
 
        sid = devm_kzalloc(dev, sizeof(*sid), GFP_KERNEL);
@@ -131,6 +131,11 @@ static int sunxi_sid_probe(struct platform_device *pdev)
                return PTR_ERR(nvmem);
 
        randomness = kzalloc(sizeof(u8) * size, GFP_KERNEL);
+       if (!randomness) {
+               ret = -EINVAL;
+               goto err_unreg_nvmem;
+       }
+
        for (i = 0; i < size; i++)
                randomness[i] = sunxi_sid_read_byte(sid, i);
 
@@ -140,6 +145,10 @@ static int sunxi_sid_probe(struct platform_device *pdev)
        platform_set_drvdata(pdev, nvmem);
 
        return 0;
+
+err_unreg_nvmem:
+       nvmem_unregister(nvmem);
+       return ret;
 }
 
 static int sunxi_sid_remove(struct platform_device *pdev)