Merge tag 'kspp-misc-fixes-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

Pull hardening fixes and cleanups from Gustavo A. R. Silva:
 "Various hardening fixes and cleanups that I've been collecting during
  the last development cycle:

  Fix -Wcast-function-type error:

   - firewire: Remove function callback casts (Oscar Carter)

  Fix application of sizeof operator:

   - firmware/psci: fix application of sizeof to pointer (jing yangyang)

  Replace open coded instances with size_t saturating arithmetic
  helpers:

   - assoc_array: Avoid open coded arithmetic in allocator arguments
     (Len Baker)

   - writeback: prefer struct_size over open coded arithmetic (Len
     Baker)

   - aio: Prefer struct_size over open coded arithmetic (Len Baker)

   - dmaengine: pxa_dma: Prefer struct_size over open coded arithmetic
     (Len Baker)

  Flexible array transformation:

   - KVM: PPC: Replace zero-length array with flexible array member (Len
     Baker)

  Use 2-factor argument multiplication form:

   - nouveau/svm: Use kvcalloc() instead of kvzalloc() (Gustavo A. R.
     Silva)

   - xfs: Use kvcalloc() instead of kvzalloc() (Gustavo A. R. Silva)"

* tag 'kspp-misc-fixes-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  firewire: Remove function callback casts
  nouveau/svm: Use kvcalloc() instead of kvzalloc()
  firmware/psci: fix application of sizeof to pointer
  dmaengine: pxa_dma: Prefer struct_size over open coded arithmetic
  KVM: PPC: Replace zero-length array with flexible array member
  aio: Prefer struct_size over open coded arithmetic
  writeback: prefer struct_size over open coded arithmetic
  xfs: Use kvcalloc() instead of kvzalloc()
  assoc_array: Avoid open coded arithmetic in allocator arguments

11 files changed, 55 insertions, 37 deletions

diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 080a7feb773180..3aed653373a5d4 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -190,7 +190,7 @@ struct kvmppc_spapr_tce_table {
 	u64 size;		/* window size in pages */
 	struct list_head iommu_tables;
 	struct mutex alloc_lock;
-	struct page *pages[0];
+	struct page *pages[];
 };
 
 /* XICS components, defined in book3s_xics.c */
diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c
index 6365087f316024..d42b4b6d4a791d 100644
--- a/arch/powerpc/kvm/book3s_64_vio.c
+++ b/arch/powerpc/kvm/book3s_64_vio.c
@@ -295,8 +295,7 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
 		return ret;
 
 	ret = -ENOMEM;
-	stt = kzalloc(sizeof(*stt) + npages * sizeof(struct page *),
-		      GFP_KERNEL);
+	stt = kzalloc(struct_size(stt, pages, npages), GFP_KERNEL);
 	if (!stt)
 		goto fail_acct;
 
diff --git a/drivers/dma/pxa_dma.c b/drivers/dma/pxa_dma.c
index 4a2a796e348c10..52d04641e3611f 100644
--- a/drivers/dma/pxa_dma.c
+++ b/drivers/dma/pxa_dma.c
@@ -742,8 +742,7 @@ pxad_alloc_desc(struct pxad_chan *chan, unsigned int nb_hw_desc)
 	dma_addr_t dma;
 	int i;
 
-	sw_desc = kzalloc(sizeof(*sw_desc) +
-			  nb_hw_desc * sizeof(struct pxad_desc_hw *),
+	sw_desc = kzalloc(struct_size(sw_desc, hw_desc, nb_hw_desc),
 			  GFP_NOWAIT);
 	if (!sw_desc)
 		return NULL;
diff --git a/drivers/firewire/core-cdev.c b/drivers/firewire/core-cdev.c
index fb6c651214f323..9f89c17730b124 100644
--- a/drivers/firewire/core-cdev.c
+++ b/drivers/firewire/core-cdev.c
@@ -10,6 +10,7 @@
 #include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/dma-mapping.h>
+#include <linux/err.h>
 #include <linux/errno.h>
 #include <linux/firewire.h>
 #include <linux/firewire-cdev.h>
@@ -953,11 +954,25 @@ static enum dma_data_direction iso_dma_direction(struct fw_iso_context *context)
 			return DMA_FROM_DEVICE;
 }
 
+static struct fw_iso_context *fw_iso_mc_context_create(struct fw_card *card,
+						fw_iso_mc_callback_t callback,
+						void *callback_data)
+{
+	struct fw_iso_context *ctx;
+
+	ctx = fw_iso_context_create(card, FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL,
+				    0, 0, 0, NULL, callback_data);
+	if (!IS_ERR(ctx))
+		ctx->callback.mc = callback;
+
+	return ctx;
+}
+
 static int ioctl_create_iso_context(struct client *client, union ioctl_arg *arg)
 {
 	struct fw_cdev_create_iso_context *a = &arg->create_iso_context;
 	struct fw_iso_context *context;
-	fw_iso_callback_t cb;
+	union fw_iso_callback cb;
 	int ret;
 
 	BUILD_BUG_ON(FW_CDEV_ISO_CONTEXT_TRANSMIT != FW_ISO_CONTEXT_TRANSMIT ||
@@ -970,7 +985,7 @@ static int ioctl_create_iso_context(struct client *client, union ioctl_arg *arg)
 		if (a->speed > SCODE_3200 || a->channel > 63)
 			return -EINVAL;
 
-		cb = iso_callback;
+		cb.sc = iso_callback;
 		break;
 
 	case FW_ISO_CONTEXT_RECEIVE:
@@ -978,19 +993,24 @@ static int ioctl_create_iso_context(struct client *client, union ioctl_arg *arg)
 		    a->channel > 63)
 			return -EINVAL;
 
-		cb = iso_callback;
+		cb.sc = iso_callback;
 		break;
 
 	case FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL:
-		cb = (fw_iso_callback_t)iso_mc_callback;
+		cb.mc = iso_mc_callback;
 		break;
 
 	default:
 		return -EINVAL;
 	}
 
-	context = fw_iso_context_create(client->device->card, a->type,
-			a->channel, a->speed, a->header_size, cb, client);
+	if (a->type == FW_ISO_CONTEXT_RECEIVE_MULTICHANNEL)
+		context = fw_iso_mc_context_create(client->device->card, cb.mc,
+						   client);
+	else
+		context = fw_iso_context_create(client->device->card, a->type,
+						a->channel, a->speed,
+						a->header_size, cb.sc, client);
 	if (IS_ERR(context))
 		return PTR_ERR(context);
 	if (client->version < FW_CDEV_VERSION_AUTO_FLUSH_ISO_OVERFLOW)
diff --git a/drivers/firmware/psci/psci_checker.c b/drivers/firmware/psci/psci_checker.c
index 9a369a2eda71d2..116eb465cdb422 100644
--- a/drivers/firmware/psci/psci_checker.c
+++ b/drivers/firmware/psci/psci_checker.c
@@ -155,7 +155,7 @@ static int alloc_init_cpu_groups(cpumask_var_t **pcpu_groups)
 	if (!alloc_cpumask_var(&tmp, GFP_KERNEL))
 		return -ENOMEM;
 
-	cpu_groups = kcalloc(nb_available_cpus, sizeof(cpu_groups),
+	cpu_groups = kcalloc(nb_available_cpus, sizeof(*cpu_groups),
 			     GFP_KERNEL);
 	if (!cpu_groups) {
 		free_cpumask_var(tmp);
diff --git a/drivers/gpu/drm/nouveau/nouveau_svm.c b/drivers/gpu/drm/nouveau/nouveau_svm.c
index b0c3422cb01fa5..1a896a24288aa2 100644
--- a/drivers/gpu/drm/nouveau/nouveau_svm.c
+++ b/drivers/gpu/drm/nouveau/nouveau_svm.c
@@ -992,7 +992,7 @@ nouveau_svm_fault_buffer_ctor(struct nouveau_svm *svm, s32 oclass, int id)
 	if (ret)
 		return ret;
 
-	buffer->fault = kvzalloc(sizeof(*buffer->fault) * buffer->entries, GFP_KERNEL);
+	buffer->fault = kvcalloc(sizeof(*buffer->fault), buffer->entries, GFP_KERNEL);
 	if (!buffer->fault)
 		return -ENOMEM;
 
diff --git a/fs/aio.c b/fs/aio.c
index 836dc7e48db75d..9c81cf611d659f 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -659,8 +659,7 @@ static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm)
 		new_nr = (table ? table->nr : 1) * 4;
 		spin_unlock(&mm->ioctx_lock);
 
-		table = kzalloc(sizeof(*table) + sizeof(struct kioctx *) *
-				new_nr, GFP_KERNEL);
+		table = kzalloc(struct_size(table, table, new_nr), GFP_KERNEL);
 		if (!table)
 			return -ENOMEM;
 
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 4124a89a1a5df5..67f0e88eed01ae 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -566,7 +566,7 @@ static void inode_switch_wbs(struct inode *inode, int new_wb_id)
 	if (atomic_read(&isw_nr_in_flight) > WB_FRN_MAX_IN_FLIGHT)
 		return;
 
-	isw = kzalloc(sizeof(*isw) + 2 * sizeof(struct inode *), GFP_ATOMIC);
+	isw = kzalloc(struct_size(isw, inodes, 2), GFP_ATOMIC);
 	if (!isw)
 		return;
 
@@ -624,8 +624,8 @@ bool cleanup_offline_cgwb(struct bdi_writeback *wb)
 	int nr;
 	bool restart = false;
 
-	isw = kzalloc(sizeof(*isw) + WB_MAX_INODES_PER_ISW *
-		      sizeof(struct inode *), GFP_KERNEL);
+	isw = kzalloc(struct_size(isw, inodes, WB_MAX_INODES_PER_ISW),
+		      GFP_KERNEL);
 	if (!isw)
 		return restart;
 
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 0c795dc093efac..174cd8950cb672 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1547,7 +1547,7 @@ xfs_ioc_getbmap(
 	if (bmx.bmv_count > ULONG_MAX / recsize)
 		return -ENOMEM;
 
-	buf = kvzalloc(bmx.bmv_count * sizeof(*buf), GFP_KERNEL);
+	buf = kvcalloc(bmx.bmv_count, sizeof(*buf), GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;
 
@@ -1601,11 +1601,11 @@ xfs_ioc_getfsmap(
 	 */
 	count = min_t(unsigned int, head.fmh_count,
 			131072 / sizeof(struct fsmap));
-	recs = kvzalloc(count * sizeof(struct fsmap), GFP_KERNEL);
+	recs = kvcalloc(count, sizeof(struct fsmap), GFP_KERNEL);
 	if (!recs) {
 		count = min_t(unsigned int, head.fmh_count,
 				PAGE_SIZE / sizeof(struct fsmap));
-		recs = kvzalloc(count * sizeof(struct fsmap), GFP_KERNEL);
+		recs = kvcalloc(count, sizeof(struct fsmap), GFP_KERNEL);
 		if (!recs)
 			return -ENOMEM;
 	}
diff --git a/include/linux/firewire.h b/include/linux/firewire.h
index aec8f30ab200de..07967a450eaad0 100644
--- a/include/linux/firewire.h
+++ b/include/linux/firewire.h
@@ -436,6 +436,12 @@ typedef void (*fw_iso_callback_t)(struct fw_iso_context *context,
 				  void *header, void *data);
 typedef void (*fw_iso_mc_callback_t)(struct fw_iso_context *context,
 				     dma_addr_t completed, void *data);
+
+union fw_iso_callback {
+	fw_iso_callback_t sc;
+	fw_iso_mc_callback_t mc;
+};
+
 struct fw_iso_context {
 	struct fw_card *card;
 	int type;
@@ -443,10 +449,7 @@ struct fw_iso_context {
 	int speed;
 	bool drop_overflow_headers;
 	size_t header_size;
-	union {
-		fw_iso_callback_t sc;
-		fw_iso_mc_callback_t mc;
-	} callback;
+	union fw_iso_callback callback;
 	void *callback_data;
 };
 
diff --git a/lib/assoc_array.c b/lib/assoc_array.c
index 04c98799c3baf2..079c72e26493ed 100644
--- a/lib/assoc_array.c
+++ b/lib/assoc_array.c
@@ -741,8 +741,7 @@ all_leaves_cluster_together:
 	keylen = round_up(diff, ASSOC_ARRAY_KEY_CHUNK_SIZE);
 	keylen >>= ASSOC_ARRAY_KEY_CHUNK_SHIFT;
 
-	new_s0 = kzalloc(sizeof(struct assoc_array_shortcut) +
-			 keylen * sizeof(unsigned long), GFP_KERNEL);
+	new_s0 = kzalloc(struct_size(new_s0, index_key, keylen), GFP_KERNEL);
 	if (!new_s0)
 		return false;
 	edit->new_meta[2] = assoc_array_shortcut_to_ptr(new_s0);
@@ -849,8 +848,8 @@ static bool assoc_array_insert_mid_shortcut(struct assoc_array_edit *edit,
 		keylen = round_up(diff, ASSOC_ARRAY_KEY_CHUNK_SIZE);
 		keylen >>= ASSOC_ARRAY_KEY_CHUNK_SHIFT;
 
-		new_s0 = kzalloc(sizeof(struct assoc_array_shortcut) +
-				 keylen * sizeof(unsigned long), GFP_KERNEL);
+		new_s0 = kzalloc(struct_size(new_s0, index_key, keylen),
+				 GFP_KERNEL);
 		if (!new_s0)
 			return false;
 		edit->new_meta[1] = assoc_array_shortcut_to_ptr(new_s0);
@@ -864,7 +863,7 @@ static bool assoc_array_insert_mid_shortcut(struct assoc_array_edit *edit,
 		new_n0->parent_slot = 0;
 
 		memcpy(new_s0->index_key, shortcut->index_key,
-		       keylen * sizeof(unsigned long));
+		       flex_array_size(new_s0, index_key, keylen));
 
 		blank = ULONG_MAX << (diff & ASSOC_ARRAY_KEY_CHUNK_MASK);
 		pr_devel("blank off [%zu] %d: %lx\n", keylen - 1, diff, blank);
@@ -899,8 +898,8 @@ static bool assoc_array_insert_mid_shortcut(struct assoc_array_edit *edit,
 		keylen = round_up(shortcut->skip_to_level, ASSOC_ARRAY_KEY_CHUNK_SIZE);
 		keylen >>= ASSOC_ARRAY_KEY_CHUNK_SHIFT;
 
-		new_s1 = kzalloc(sizeof(struct assoc_array_shortcut) +
-				 keylen * sizeof(unsigned long), GFP_KERNEL);
+		new_s1 = kzalloc(struct_size(new_s1, index_key, keylen),
+				 GFP_KERNEL);
 		if (!new_s1)
 			return false;
 		edit->new_meta[2] = assoc_array_shortcut_to_ptr(new_s1);
@@ -913,7 +912,7 @@ static bool assoc_array_insert_mid_shortcut(struct assoc_array_edit *edit,
 		new_n0->slots[sc_slot] = assoc_array_shortcut_to_ptr(new_s1);
 
 		memcpy(new_s1->index_key, shortcut->index_key,
-		       keylen * sizeof(unsigned long));
+		       flex_array_size(new_s1, index_key, keylen));
 
 		edit->set[1].ptr = &side->back_pointer;
 		edit->set[1].to = assoc_array_shortcut_to_ptr(new_s1);
@@ -1490,13 +1489,12 @@ descend:
 		shortcut = assoc_array_ptr_to_shortcut(cursor);
 		keylen = round_up(shortcut->skip_to_level, ASSOC_ARRAY_KEY_CHUNK_SIZE);
 		keylen >>= ASSOC_ARRAY_KEY_CHUNK_SHIFT;
-		new_s = kmalloc(sizeof(struct assoc_array_shortcut) +
-				keylen * sizeof(unsigned long), GFP_KERNEL);
+		new_s = kmalloc(struct_size(new_s, index_key, keylen),
+				GFP_KERNEL);
 		if (!new_s)
 			goto enomem;
 		pr_devel("dup shortcut %p -> %p\n", shortcut, new_s);
-		memcpy(new_s, shortcut, (sizeof(struct assoc_array_shortcut) +
-					 keylen * sizeof(unsigned long)));
+		memcpy(new_s, shortcut, struct_size(new_s, index_key, keylen));
 		new_s->back_pointer = new_parent;
 		new_s->parent_slot = shortcut->parent_slot;
 		*new_ptr_pp = new_parent = assoc_array_shortcut_to_ptr(new_s);