i2c: mux: reg: check return value after calling platform_get_resource()

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: b3fdd32799 ("i2c: mux: Add register-based mux i2c-mux-reg")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
This commit is contained in:
Yang Yingliang 2022-10-29 17:38:25 +08:00 committed by Wolfram Sang
parent 810199f731
commit 2d47b79d2b
1 changed files with 2 additions and 3 deletions

View File

@ -183,13 +183,12 @@ static int i2c_mux_reg_probe(struct platform_device *pdev)
if (!mux->data.reg) {
dev_info(&pdev->dev,
"Register not set, using platform resource\n");
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
mux->data.reg_size = resource_size(res);
mux->data.reg = devm_ioremap_resource(&pdev->dev, res);
mux->data.reg = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
if (IS_ERR(mux->data.reg)) {
ret = PTR_ERR(mux->data.reg);
goto err_put_parent;
}
mux->data.reg_size = resource_size(res);
}
if (mux->data.reg_size != 4 && mux->data.reg_size != 2 &&