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

8 files changed, 14 insertions, 18 deletions

diff --git a/drivers/dma/bcm-sba-raid.c b/drivers/dma/bcm-sba-raid.c
index 3956a018bf5ac..72878ac5c78d6 100644
--- a/drivers/dma/bcm-sba-raid.c
+++ b/drivers/dma/bcm-sba-raid.c
@@ -1499,9 +1499,8 @@ static int sba_prealloc_channel_resources(struct sba_device *sba)
 
 	for (i = 0; i < sba->max_req; i++) {
 		req = devm_kzalloc(sba->dev,
-				sizeof(*req) +
-				sba->max_cmd_per_req * sizeof(req->cmds[0]),
-				GFP_KERNEL);
+				   struct_size(req, cmds, sba->max_cmd_per_req),
+				   GFP_KERNEL);
 		if (!req) {
 			ret = -ENOMEM;
 			goto fail_free_cmds_pool;
diff --git a/drivers/dma/edma.c b/drivers/dma/edma.c
index 85ea92fcea540..9bc722ca83299 100644
--- a/drivers/dma/edma.c
+++ b/drivers/dma/edma.c
@@ -1074,8 +1074,7 @@ static struct dma_async_tx_descriptor *edma_prep_slave_sg(
 		return NULL;
 	}
 
-	edesc = kzalloc(sizeof(*edesc) + sg_len * sizeof(edesc->pset[0]),
-			GFP_ATOMIC);
+	edesc = kzalloc(struct_size(edesc, pset, sg_len), GFP_ATOMIC);
 	if (!edesc)
 		return NULL;
 
@@ -1192,8 +1191,7 @@ static struct dma_async_tx_descriptor *edma_prep_dma_memcpy(
 			nslots = 2;
 	}
 
-	edesc = kzalloc(sizeof(*edesc) + nslots * sizeof(edesc->pset[0]),
-			GFP_ATOMIC);
+	edesc = kzalloc(struct_size(edesc, pset, nslots), GFP_ATOMIC);
 	if (!edesc)
 		return NULL;
 
@@ -1315,8 +1313,7 @@ static struct dma_async_tx_descriptor *edma_prep_dma_cyclic(
 		}
 	}
 
-	edesc = kzalloc(sizeof(*edesc) + nslots * sizeof(edesc->pset[0]),
-			GFP_ATOMIC);
+	edesc = kzalloc(struct_size(edesc, pset, nslots), GFP_ATOMIC);
 	if (!edesc)
 		return NULL;
 
diff --git a/drivers/dma/moxart-dma.c b/drivers/dma/moxart-dma.c
index e1a5c2242f6fb..e04499c1f27f4 100644
--- a/drivers/dma/moxart-dma.c
+++ b/drivers/dma/moxart-dma.c
@@ -309,7 +309,7 @@ static struct dma_async_tx_descriptor *moxart_prep_slave_sg(
 		return NULL;
 	}
 
-	d = kzalloc(sizeof(*d) + sg_len * sizeof(d->sg[0]), GFP_ATOMIC);
+	d = kzalloc(struct_size(d, sg, sg_len), GFP_ATOMIC);
 	if (!d)
 		return NULL;
 
diff --git a/drivers/dma/nbpfaxi.c b/drivers/dma/nbpfaxi.c
index 50559338239b6..2f9974ddfbb2f 100644
--- a/drivers/dma/nbpfaxi.c
+++ b/drivers/dma/nbpfaxi.c
@@ -1305,8 +1305,8 @@ static int nbpf_probe(struct platform_device *pdev)
 	cfg = of_device_get_match_data(dev);
 	num_channels = cfg->num_channels;
 
-	nbpf = devm_kzalloc(dev, sizeof(*nbpf) + num_channels *
-			    sizeof(nbpf->chan[0]), GFP_KERNEL);
+	nbpf = devm_kzalloc(dev, struct_size(nbpf, chan, num_channels),
+			    GFP_KERNEL);
 	if (!nbpf)
 		return -ENOMEM;
 
diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
index d21c19822feb9..9483000fcf79a 100644
--- a/drivers/dma/omap-dma.c
+++ b/drivers/dma/omap-dma.c
@@ -917,7 +917,7 @@ static struct dma_async_tx_descriptor *omap_dma_prep_slave_sg(
 	}
 
 	/* Now allocate and setup the descriptor. */
-	d = kzalloc(sizeof(*d) + sglen * sizeof(d->sg[0]), GFP_ATOMIC);
+	d = kzalloc(struct_size(d, sg, sglen), GFP_ATOMIC);
 	if (!d)
 		return NULL;
 
diff --git a/drivers/dma/sa11x0-dma.c b/drivers/dma/sa11x0-dma.c
index c7a89c22890e5..b31d07c7d93c1 100644
--- a/drivers/dma/sa11x0-dma.c
+++ b/drivers/dma/sa11x0-dma.c
@@ -557,7 +557,7 @@ static struct dma_async_tx_descriptor *sa11x0_dma_prep_slave_sg(
 		}
 	}
 
-	txd = kzalloc(sizeof(*txd) + j * sizeof(txd->sg[0]), GFP_ATOMIC);
+	txd = kzalloc(struct_size(txd, sg, j), GFP_ATOMIC);
 	if (!txd) {
 		dev_dbg(chan->device->dev, "vchan %p: kzalloc failed\n", &c->vc);
 		return NULL;
@@ -627,7 +627,7 @@ static struct dma_async_tx_descriptor *sa11x0_dma_prep_dma_cyclic(
 	if (sglen == 0)
 		return NULL;
 
-	txd = kzalloc(sizeof(*txd) + sglen * sizeof(txd->sg[0]), GFP_ATOMIC);
+	txd = kzalloc(struct_size(txd, sg, sglen), GFP_ATOMIC);
 	if (!txd) {
 		dev_dbg(chan->device->dev, "vchan %p: kzalloc failed\n", &c->vc);
 		return NULL;
diff --git a/drivers/dma/sh/usb-dmac.c b/drivers/dma/sh/usb-dmac.c
index 31a145154e9f2..1bb1a8e09025f 100644
--- a/drivers/dma/sh/usb-dmac.c
+++ b/drivers/dma/sh/usb-dmac.c
@@ -269,7 +269,7 @@ static int usb_dmac_desc_alloc(struct usb_dmac_chan *chan, unsigned int sg_len,
 	struct usb_dmac_desc *desc;
 	unsigned long flags;
 
-	desc = kzalloc(sizeof(*desc) + sg_len * sizeof(desc->sg[0]), gfp);
+	desc = kzalloc(struct_size(desc, sg, sg_len), gfp);
 	if (!desc)
 		return -ENOMEM;
 
diff --git a/drivers/dma/sprd-dma.c b/drivers/dma/sprd-dma.c
index b106e8a60af64..52ebccb483bed 100644
--- a/drivers/dma/sprd-dma.c
+++ b/drivers/dma/sprd-dma.c
@@ -805,8 +805,8 @@ static int sprd_dma_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	sdev = devm_kzalloc(&pdev->dev, sizeof(*sdev) +
-			    sizeof(*dma_chn) * chn_count,
+	sdev = devm_kzalloc(&pdev->dev,
+			    struct_size(sdev, channels, chn_count),
 			    GFP_KERNEL);
 	if (!sdev)
 		return -ENOMEM;