From: Yang Yingliang yangyingliang@huawei.com
commit a15932f4377062364d22096afe25bc579134a1c3 upstream.
It will cause null-ptr-deref in resource_size(), if platform_get_resource() returns NULL, move calling resource_size() after devm_ioremap_resource() that will check 'res' to avoid null-ptr-deref. And use devm_platform_get_and_ioremap_resource() to simplify code.
Fixes: 46d1fb072e76 ("iommu/dart: Add DART iommu driver") Signed-off-by: Yang Yingliang yangyingliang@huawei.com Reviewed-by: Sven Peter sven@svenpeter.dev Link: https://lore.kernel.org/r/20220425090826.2532165-1-yangyingliang@huawei.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iommu/apple-dart.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
--- a/drivers/iommu/apple-dart.c +++ b/drivers/iommu/apple-dart.c @@ -857,16 +857,15 @@ static int apple_dart_probe(struct platf dart->dev = dev; spin_lock_init(&dart->lock);
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + dart->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res); + if (IS_ERR(dart->regs)) + return PTR_ERR(dart->regs); + if (resource_size(res) < 0x4000) { dev_err(dev, "MMIO region too small (%pr)\n", res); return -EINVAL; }
- dart->regs = devm_ioremap_resource(dev, res); - if (IS_ERR(dart->regs)) - return PTR_ERR(dart->regs); - dart->irq = platform_get_irq(pdev, 0); if (dart->irq < 0) return -ENODEV;