serial: amba-pl011: Fix devm_ioremap_resource return value check

Value returned by devm_ioremap_resource() was checked for non-NULL but
devm_ioremap_resource() returns IOMEM_ERR_PTR, not NULL. In case of
error this could lead to dereference of ERR_PTR.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Cc: <stable@vger.kernel.org>
Fixes: 3873e2d7f63a ("drivers: PL011: refactor pl011_probe()")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 50cf5b10ceed98022cbc44609acd280ef2beba81..fd27e986b1dd3437dfd2560ec11efd8def7bf254 100644 (file)
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -2310,8 +2310,8 @@ static int pl011_setup_port(struct device *dev, struct uart_amba_port *uap,
        void __iomem *base;
 
        base = devm_ioremap_resource(dev, mmiobase);
-       if (!base)
-               return -ENOMEM;
+       if (IS_ERR(base))
+               return PTR_ERR(base);
 
        index = pl011_probe_dt_alias(index, dev);