hwspinlock: sprd: Use struct_size() helper in devm_kzalloc()

Make use of the struct_size() helper instead of an open-coded version,
in order to avoid any potential type mistakes or integer overflows that,
in the worst scenario, could lead to heap overflows.

Also, address the following sparse warnings:
drivers/hwspinlock/sprd_hwspinlock.c:96:36: warning: using sizeof on a flexible structure

Link: https://github.com/KSPP/linux/issues/174
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220125225723.GA78256@embeddedor

diff --git a/drivers/hwspinlock/sprd_hwspinlock.c b/drivers/hwspinlock/sprd_hwspinlock.c
index d221fc9d756d65a713cc46d659dfab235642f0e9..22e2ffb9174362fd6e88451c28dfd78b478fdb8b 100644 (file)
--- a/drivers/hwspinlock/sprd_hwspinlock.c
+++ b/drivers/hwspinlock/sprd_hwspinlock.c
@@ -93,8 +93,7 @@ static int sprd_hwspinlock_probe(struct platform_device *pdev)
                return -ENODEV;
 
        sprd_hwlock = devm_kzalloc(&pdev->dev,
-                                  sizeof(struct sprd_hwspinlock_dev) +
-                                  SPRD_HWLOCKS_NUM * sizeof(*lock),
+                                  struct_size(sprd_hwlock, bank.lock, SPRD_HWLOCKS_NUM),
                                   GFP_KERNEL);
        if (!sprd_hwlock)
                return -ENOMEM;