Merge tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull overflow updates from Kees Cook:
 "This adds the new overflow checking helpers and adds them to the
  2-factor argument allocators. And this adds the saturating size
  helpers and does a treewide replacement for the struct_size() usage.
  Additionally this adds the overflow testing modules to make sure
  everything works.

  I'm still working on the treewide replacements for allocators with
  "simple" multiplied arguments:

     *alloc(a * b, ...) -> *alloc_array(a, b, ...)

  and

     *zalloc(a * b, ...) -> *calloc(a, b, ...)

  as well as the more complex cases, but that's separable from this
  portion of the series. I expect to have the rest sent before -rc1
  closes; there are a lot of messy cases to clean up.

  Summary:

   - Introduce arithmetic overflow test helper functions (Rasmus)

   - Use overflow helpers in 2-factor allocators (Kees, Rasmus)

   - Introduce overflow test module (Rasmus, Kees)

   - Introduce saturating size helper functions (Matthew, Kees)

   - Treewide use of struct_size() for allocators (Kees)"

* tag 'overflow-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  treewide: Use struct_size() for devm_kmalloc() and friends
  treewide: Use struct_size() for vmalloc()-family
  treewide: Use struct_size() for kmalloc()-family
  device: Use overflow helpers for devm_kmalloc()
  mm: Use overflow helpers in kvmalloc()
  mm: Use overflow helpers in kmalloc_array*()
  test_overflow: Add memory allocation overflow tests
  overflow.h: Add allocation size calculation helpers
  test_overflow: Report test failures
  test_overflow: macrofy some more, do more tests for free
  lib: add runtime test of check_*_overflow functions
  compiler.h: enable builtin overflow checkers and add fallback code

2 files changed, 2 insertions, 4 deletions

diff --git a/drivers/gpio/gpio-uniphier.c b/drivers/gpio/gpio-uniphier.c
index 761d8279abca..d3cf9502e7e7 100644
--- a/drivers/gpio/gpio-uniphier.c
+++ b/drivers/gpio/gpio-uniphier.c
@@ -371,8 +371,7 @@ static int uniphier_gpio_probe(struct platform_device *pdev)
 		return ret;
 
 	nregs = uniphier_gpio_get_nbanks(ngpios) * 2 + 3;
-	priv = devm_kzalloc(dev,
-			    sizeof(*priv) + sizeof(priv->saved_vals[0]) * nregs,
+	priv = devm_kzalloc(dev, struct_size(priv, saved_vals, nregs),
 			    GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index d8ccb500872f..55d596f3035e 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -4023,8 +4023,7 @@ struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
 	if (count < 0)
 		return ERR_PTR(count);
 
-	descs = kzalloc(sizeof(*descs) + sizeof(descs->desc[0]) * count,
-			GFP_KERNEL);
+	descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL);
 	if (!descs)
 		return ERR_PTR(-ENOMEM);