treewide: Use struct_size() for devm_kmalloc() and friends

Replaces open-coded struct size calculations with struct_size() for
devm_*, f2fs_*, and sock_* allocations. Automatically generated (and
manually adjusted) from the following Coccinelle script:

// Direct reference to struct field.
@@
identifier alloc =~ "devm_kmalloc|devm_kzalloc|sock_kmalloc|f2fs_kmalloc|f2fs_kzalloc";
expression HANDLE;
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(HANDLE, sizeof(*VAR) + COUNT * sizeof(*VAR->ELEMENT), GFP)
+ alloc(HANDLE, struct_size(VAR, ELEMENT, COUNT), GFP)

// mr = kzalloc(sizeof(*mr) + m * sizeof(mr->map[0]), GFP_KERNEL);
@@
identifier alloc =~ "devm_kmalloc|devm_kzalloc|sock_kmalloc|f2fs_kmalloc|f2fs_kzalloc";
expression HANDLE;
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(HANDLE, sizeof(*VAR) + COUNT * sizeof(VAR->ELEMENT[0]), GFP)
+ alloc(HANDLE, struct_size(VAR, ELEMENT, COUNT), GFP)

// Same pattern, but can't trivially locate the trailing element name,
// or variable name.
@@
identifier alloc =~ "devm_kmalloc|devm_kzalloc|sock_kmalloc|f2fs_kmalloc|f2fs_kzalloc";
expression HANDLE;
expression GFP;
expression SOMETHING, COUNT, ELEMENT;
@@

- alloc(HANDLE, sizeof(SOMETHING) + COUNT * sizeof(ELEMENT), GFP)
+ alloc(HANDLE, CHECKME_struct_size(&SOMETHING, ELEMENT, COUNT), GFP)

Signed-off-by: Kees Cook <keescook@chromium.org>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/hwspinlock/sirf_hwspinlock.c b/drivers/hwspinlock/sirf_hwspinlock.c
index 16018544d431..cb38e487c6c4 100644
--- a/drivers/hwspinlock/sirf_hwspinlock.c
+++ b/drivers/hwspinlock/sirf_hwspinlock.c
@@ -62,8 +62,10 @@ static int sirf_hwspinlock_probe(struct platform_device *pdev)
 	if (!pdev->dev.of_node)
 		return -ENODEV;
 
-	hwspin = devm_kzalloc(&pdev->dev, sizeof(*hwspin) +
-			sizeof(*hwlock) * HW_SPINLOCK_NUMBER, GFP_KERNEL);
+	hwspin = devm_kzalloc(&pdev->dev,
+			      struct_size(hwspin, bank.lock,
+					  HW_SPINLOCK_NUMBER),
+			      GFP_KERNEL);
 	if (!hwspin)
 		return -ENOMEM;