Merge tag 'overflow-v5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull overflow updates from Kees Cook:
 "The end goal of the current buffer overflow detection work[0] is to
  gain full compile-time and run-time coverage of all detectable buffer
  overflows seen via array indexing or memcpy(), memmove(), and
  memset(). The str*() family of functions already have full coverage.

  While much of the work for these changes have been on-going for many
  releases (i.e. 0-element and 1-element array replacements, as well as
  avoiding false positives and fixing discovered overflows[1]), this
  series contains the foundational elements of several related buffer
  overflow detection improvements by providing new common helpers and
  FORTIFY_SOURCE changes needed to gain the introspection required for
  compiler visibility into array sizes. Also included are a handful of
  already Acked instances using the helpers (or related clean-ups), with
  many more waiting at the ready to be taken via subsystem-specific
  trees[2].

  The new helpers are:

   - struct_group() for gaining struct member range introspection

   - memset_after() and memset_startat() for clearing to the end of
     structures

   - DECLARE_FLEX_ARRAY() for using flex arrays in unions or alone in
     structs

  Also included is the beginning of the refactoring of FORTIFY_SOURCE to
  support memcpy() introspection, fix missing and regressed coverage
  under GCC, and to prepare to fix the currently broken Clang support.
  Finishing this work is part of the larger series[0], but depends on
  all the false positives and buffer overflow bug fixes to have landed
  already and those that depend on this series to land.

  As part of the FORTIFY_SOURCE refactoring, a set of both a
  compile-time and run-time tests are added for FORTIFY_SOURCE and the
  mem*()-family functions respectively. The compile time tests have
  found a legitimate (though corner-case) bug[6] already.

  Please note that the appearance of "panic" and "BUG" in the
  FORTIFY_SOURCE refactoring are the result of relocating existing code,
  and no new use of those code-paths are expected nor desired.

  Finally, there are two tree-wide conversions for 0-element arrays and
  flexible array unions to gain sane compiler introspection coverage
  that result in no known object code differences.

  After this series (and the changes that have now landed via netdev and
  usb), we are very close to finally being able to build with
  -Warray-bounds and -Wzero-length-bounds.

  However, due corner cases in GCC[3] and Clang[4], I have not included
  the last two patches that turn on these options, as I don't want to
  introduce any known warnings to the build. Hopefully these can be
  solved soon"

Link: https://lore.kernel.org/lkml/20210818060533.3569517-1-keescook@chromium.org/ [0]
Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/?qt=grep&q=FORTIFY_SOURCE [1]
Link: https://lore.kernel.org/lkml/202108220107.3E26FE6C9C@keescook/ [2]
Link: https://lore.kernel.org/lkml/3ab153ec-2798-da4c-f7b1-81b0ac8b0c5b@roeck-us.net/ [3]
Link: https://bugs.llvm.org/show_bug.cgi?id=51682 [4]
Link: https://lore.kernel.org/lkml/202109051257.29B29745C0@keescook/ [5]
Link: https://lore.kernel.org/lkml/20211020200039.170424-1-keescook@chromium.org/ [6]

* tag 'overflow-v5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (30 commits)
  fortify: strlen: Avoid shadowing previous locals
  compiler-gcc.h: Define __SANITIZE_ADDRESS__ under hwaddress sanitizer
  treewide: Replace 0-element memcpy() destinations with flexible arrays
  treewide: Replace open-coded flex arrays in unions
  stddef: Introduce DECLARE_FLEX_ARRAY() helper
  btrfs: Use memset_startat() to clear end of struct
  string.h: Introduce memset_startat() for wiping trailing members and padding
  xfrm: Use memset_after() to clear padding
  string.h: Introduce memset_after() for wiping trailing members/padding
  lib: Introduce CONFIG_MEMCPY_KUNIT_TEST
  fortify: Add compile-time FORTIFY_SOURCE tests
  fortify: Allow strlen() and strnlen() to pass compile-time known lengths
  fortify: Prepare to improve strnlen() and strlen() warnings
  fortify: Fix dropped strcpy() compile-time write overflow check
  fortify: Explicitly disable Clang support
  fortify: Move remaining fortify helpers into fortify-string.h
  lib/string: Move helper functions out of string.c
  compiler_types.h: Remove __compiletime_object_size()
  cm4000_cs: Use struct_group() to zero struct cm4000_dev region
  can: flexcan: Use struct_group() to zero struct flexcan_regs regions
  ...

25 files changed, 157 insertions, 154 deletions

diff --git a/drivers/char/pcmcia/cm4000_cs.c b/drivers/char/pcmcia/cm4000_cs.c
index 8f1bce0b4fe5..adaec8fd4b16 100644
--- a/drivers/char/pcmcia/cm4000_cs.c
+++ b/drivers/char/pcmcia/cm4000_cs.c
@@ -116,8 +116,9 @@ struct cm4000_dev {
 	wait_queue_head_t atrq;		/* wait for ATR valid */
 	wait_queue_head_t readq;	/* used by write to wake blk.read */
 
-	/* warning: do not move this fields.
+	/* warning: do not move this struct group.
 	 * initialising to zero depends on it - see ZERO_DEV below.  */
+	struct_group(init,
 	unsigned char atr_csum;
 	unsigned char atr_len_retry;
 	unsigned short atr_len;
@@ -140,12 +141,10 @@ struct cm4000_dev {
 
 	struct timer_list timer;	/* used to keep monitor running */
 	int monitor_running;
+	);
 };
 
-#define	ZERO_DEV(dev)  						\
-	memset(&dev->atr_csum,0,				\
-		sizeof(struct cm4000_dev) - 			\
-		offsetof(struct cm4000_dev, atr_csum))
+#define	ZERO_DEV(dev)	memset(&((dev)->init), 0, sizeof((dev)->init))
 
 static struct pcmcia_device *dev_table[CM4000_MAX_DEV];
 static struct class *cmm_class;
diff --git a/drivers/crypto/chelsio/chcr_crypto.h b/drivers/crypto/chelsio/chcr_crypto.h
index e89f9e0094b4..c7816c83e324 100644
--- a/drivers/crypto/chelsio/chcr_crypto.h
+++ b/drivers/crypto/chelsio/chcr_crypto.h
@@ -222,8 +222,10 @@ struct chcr_authenc_ctx {
 };
 
 struct __aead_ctx {
-	struct chcr_gcm_ctx gcm[0];
-	struct chcr_authenc_ctx authenc[];
+	union {
+		DECLARE_FLEX_ARRAY(struct chcr_gcm_ctx, gcm);
+		DECLARE_FLEX_ARRAY(struct chcr_authenc_ctx, authenc);
+	};
 };
 
 struct chcr_aead_ctx {
@@ -245,9 +247,11 @@ struct hmac_ctx {
 };
 
 struct __crypto_ctx {
-	struct hmac_ctx hmacctx[0];
-	struct ablk_ctx ablkctx[0];
-	struct chcr_aead_ctx aeadctx[];
+	union {
+		DECLARE_FLEX_ARRAY(struct hmac_ctx, hmacctx);
+		DECLARE_FLEX_ARRAY(struct ablk_ctx, ablkctx);
+		DECLARE_FLEX_ARRAY(struct chcr_aead_ctx, aeadctx);
+	};
 };
 
 struct chcr_context {
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index 53927f9fa77e..9db0c402c9ce 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -75,52 +75,27 @@ static inline int cxl_hdm_decoder_count(u32 cap_hdr)
 #define CXLDEV_MBOX_BG_CMD_STATUS_OFFSET 0x18
 #define CXLDEV_MBOX_PAYLOAD_OFFSET 0x20
 
-#define CXL_COMPONENT_REGS() \
-	void __iomem *hdm_decoder
-
-#define CXL_DEVICE_REGS() \
-	void __iomem *status; \
-	void __iomem *mbox; \
-	void __iomem *memdev
-
-/* See note for 'struct cxl_regs' for the rationale of this organization */
-/*
- * CXL_COMPONENT_REGS - Common set of CXL Component register block base pointers
- * @hdm_decoder: CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure
- */
-struct cxl_component_regs {
-	CXL_COMPONENT_REGS();
-};
-
-/* See note for 'struct cxl_regs' for the rationale of this organization */
-/*
- * CXL_DEVICE_REGS - Common set of CXL Device register block base pointers
- * @status: CXL 2.0 8.2.8.3 Device Status Registers
- * @mbox: CXL 2.0 8.2.8.4 Mailbox Registers
- * @memdev: CXL 2.0 8.2.8.5 Memory Device Registers
- */
-struct cxl_device_regs {
-	CXL_DEVICE_REGS();
-};
-
 /*
- * Note, the anonymous union organization allows for per
- * register-block-type helper routines, without requiring block-type
- * agnostic code to include the prefix.
+ * Using struct_group() allows for per register-block-type helper routines,
+ * without requiring block-type agnostic code to include the prefix.
  */
 struct cxl_regs {
-	union {
-		struct {
-			CXL_COMPONENT_REGS();
-		};
-		struct cxl_component_regs component;
-	};
-	union {
-		struct {
-			CXL_DEVICE_REGS();
-		};
-		struct cxl_device_regs device_regs;
-	};
+	/*
+	 * Common set of CXL Component register block base pointers
+	 * @hdm_decoder: CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure
+	 */
+	struct_group_tagged(cxl_component_regs, component,
+		void __iomem *hdm_decoder;
+	);
+	/*
+	 * Common set of CXL Device register block base pointers
+	 * @status: CXL 2.0 8.2.8.3 Device Status Registers
+	 * @mbox: CXL 2.0 8.2.8.4 Mailbox Registers
+	 * @memdev: CXL 2.0 8.2.8.5 Memory Device Registers
+	 */
+	struct_group_tagged(cxl_device_regs, device_regs,
+		void __iomem *status, *mbox, *memdev;
+	);
 };
 
 struct cxl_reg_map {
diff --git a/drivers/gpu/drm/mga/mga_ioc32.c b/drivers/gpu/drm/mga/mga_ioc32.c
index 4fd4de16cd32..894472921c30 100644
--- a/drivers/gpu/drm/mga/mga_ioc32.c
+++ b/drivers/gpu/drm/mga/mga_ioc32.c
@@ -38,16 +38,18 @@
 typedef struct drm32_mga_init {
 	int func;
 	u32 sarea_priv_offset;
-	int chipset;
-	int sgram;
-	unsigned int maccess;
-	unsigned int fb_cpp;
-	unsigned int front_offset, front_pitch;
-	unsigned int back_offset, back_pitch;
-	unsigned int depth_cpp;
-	unsigned int depth_offset, depth_pitch;
-	unsigned int texture_offset[MGA_NR_TEX_HEAPS];
-	unsigned int texture_size[MGA_NR_TEX_HEAPS];
+	struct_group(always32bit,
+		int chipset;
+		int sgram;
+		unsigned int maccess;
+		unsigned int fb_cpp;
+		unsigned int front_offset, front_pitch;
+		unsigned int back_offset, back_pitch;
+		unsigned int depth_cpp;
+		unsigned int depth_offset, depth_pitch;
+		unsigned int texture_offset[MGA_NR_TEX_HEAPS];
+		unsigned int texture_size[MGA_NR_TEX_HEAPS];
+	);
 	u32 fb_offset;
 	u32 mmio_offset;
 	u32 status_offset;
@@ -67,9 +69,8 @@ static int compat_mga_init(struct file *file, unsigned int cmd,
 
 	init.func = init32.func;
 	init.sarea_priv_offset = init32.sarea_priv_offset;
-	memcpy(&init.chipset, &init32.chipset,
-		offsetof(drm_mga_init_t, fb_offset) -
-		offsetof(drm_mga_init_t, chipset));
+	memcpy(&init.always32bit, &init32.always32bit,
+	       sizeof(init32.always32bit));
 	init.fb_offset = init32.fb_offset;
 	init.mmio_offset = init32.mmio_offset;
 	init.status_offset = init32.status_offset;
diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c
index 477baa30889c..ece147d1a278 100644
--- a/drivers/hid/hid-cp2112.c
+++ b/drivers/hid/hid-cp2112.c
@@ -129,10 +129,12 @@ struct cp2112_xfer_status_report {
 
 struct cp2112_string_report {
 	u8 dummy;		/* force .string to be aligned */
-	u8 report;		/* CP2112_*_STRING */
-	u8 length;		/* length in bytes of everyting after .report */
-	u8 type;		/* USB_DT_STRING */
-	wchar_t string[30];	/* UTF16_LITTLE_ENDIAN string */
+	struct_group_attr(contents, __packed,
+		u8 report;		/* CP2112_*_STRING */
+		u8 length;		/* length in bytes of everything after .report */
+		u8 type;		/* USB_DT_STRING */
+		wchar_t string[30];	/* UTF16_LITTLE_ENDIAN string */
+	);
 } __packed;
 
 /* Number of times to request transfer status before giving up waiting for a
@@ -986,8 +988,8 @@ static ssize_t pstr_show(struct device *kdev,
 	u8 length;
 	int ret;
 
-	ret = cp2112_hid_get(hdev, attr->report, &report.report,
-			     sizeof(report) - 1, HID_FEATURE_REPORT);
+	ret = cp2112_hid_get(hdev, attr->report, (u8 *)&report.contents,
+			     sizeof(report.contents), HID_FEATURE_REPORT);
 	if (ret < 3) {
 		hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
 			ret);
diff --git a/drivers/hid/hid-roccat-kone.c b/drivers/hid/hid-roccat-kone.c
index 1ca64481145e..ea17abc7ad52 100644
--- a/drivers/hid/hid-roccat-kone.c
+++ b/drivers/hid/hid-roccat-kone.c
@@ -857,7 +857,7 @@ static int kone_raw_event(struct hid_device *hdev, struct hid_report *report,
 		memcpy(&kone->last_mouse_event, event,
 				sizeof(struct kone_mouse_event));
 	else
-		memset(&event->tilt, 0, 5);
+		memset(&event->wipe, 0, sizeof(event->wipe));
 
 	kone_keep_values_up_to_date(kone, event);
 
diff --git a/drivers/hid/hid-roccat-kone.h b/drivers/hid/hid-roccat-kone.h
index 4a1a9cb76b08..65c800e3addc 100644
--- a/drivers/hid/hid-roccat-kone.h
+++ b/drivers/hid/hid-roccat-kone.h
@@ -152,11 +152,13 @@ struct kone_mouse_event {
 	uint16_t x;
 	uint16_t y;
 	uint8_t wheel; /* up = 1, down = -1 */
-	uint8_t tilt; /* right = 1, left = -1 */
-	uint8_t unknown;
-	uint8_t event;
-	uint8_t value; /* press = 0, release = 1 */
-	uint8_t macro_key; /* 0 to 8 */
+	struct_group(wipe,
+		uint8_t tilt; /* right = 1, left = -1 */
+		uint8_t unknown;
+		uint8_t event;
+		uint8_t value; /* press = 0, release = 1 */
+		uint8_t macro_key; /* 0 to 8 */
+	);
 } __attribute__ ((__packed__));
 
 enum kone_mouse_events {
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index c6c53e18dace..1eacd43cb436 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -121,8 +121,10 @@ struct ivhd_entry {
 	u8 type;
 	u16 devid;
 	u8 flags;
-	u32 ext;
-	u32 hidh;
+	struct_group(ext_hid,
+		u32 ext;
+		u32 hidh;
+	);
 	u64 cid;
 	u8 uidf;
 	u8 uidl;
@@ -1377,7 +1379,8 @@ static int __init init_iommu_from_acpi(struct amd_iommu *iommu,
 				break;
 			}
 
-			memcpy(hid, (u8 *)(&e->ext), ACPIHID_HID_LEN - 1);
+			BUILD_BUG_ON(sizeof(e->ext_hid) != ACPIHID_HID_LEN - 1);
+			memcpy(hid, &e->ext_hid, ACPIHID_HID_LEN - 1);
 			hid[ACPIHID_HID_LEN - 1] = '\0';
 
 			if (!(*hid)) {
diff --git a/drivers/macintosh/smu.c b/drivers/macintosh/smu.c
index fe63d5ee201b..d33913d523c1 100644
--- a/drivers/macintosh/smu.c
+++ b/drivers/macintosh/smu.c
@@ -848,7 +848,8 @@ int smu_queue_i2c(struct smu_i2c_cmd *cmd)
 	cmd->read = cmd->info.devaddr & 0x01;
 	switch(cmd->info.type) {
 	case SMU_I2C_TRANSFER_SIMPLE:
-		memset(&cmd->info.sublen, 0, 4);
+		cmd->info.sublen = 0;
+		memset(cmd->info.subaddr, 0, sizeof(cmd->info.subaddr));
 		break;
 	case SMU_I2C_TRANSFER_COMBINED:
 		cmd->info.devaddr &= 0xfe;
diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index 7734229aa078..12b60ad95b02 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -290,31 +290,33 @@ struct flexcan_regs {
 	u32 dbg1;		/* 0x58 */
 	u32 dbg2;		/* 0x5c */
 	u32 _reserved3[8];	/* 0x60 */
-	u8 mb[2][512];		/* 0x80 - Not affected by Soft Reset */
-	/* FIFO-mode:
-	 *			MB
-	 * 0x080...0x08f	0	RX message buffer
-	 * 0x090...0x0df	1-5	reserved
-	 * 0x0e0...0x0ff	6-7	8 entry ID table
-	 *				(mx25, mx28, mx35, mx53)
-	 * 0x0e0...0x2df	6-7..37	8..128 entry ID table
-	 *				size conf'ed via ctrl2::RFFN
-	 *				(mx6, vf610)
-	 */
-	u32 _reserved4[256];	/* 0x480 */
-	u32 rximr[64];		/* 0x880 - Not affected by Soft Reset */
-	u32 _reserved5[24];	/* 0x980 */
-	u32 gfwr_mx6;		/* 0x9e0 - MX6 */
-	u32 _reserved6[39];	/* 0x9e4 */
-	u32 _rxfir[6];		/* 0xa80 */
-	u32 _reserved8[2];	/* 0xa98 */
-	u32 _rxmgmask;		/* 0xaa0 */
-	u32 _rxfgmask;		/* 0xaa4 */
-	u32 _rx14mask;		/* 0xaa8 */
-	u32 _rx15mask;		/* 0xaac */
-	u32 tx_smb[4];		/* 0xab0 */
-	u32 rx_smb0[4];		/* 0xac0 */
-	u32 rx_smb1[4];		/* 0xad0 */
+	struct_group(init,
+		u8 mb[2][512];		/* 0x80 - Not affected by Soft Reset */
+		/* FIFO-mode:
+		 *			MB
+		 * 0x080...0x08f	0	RX message buffer
+		 * 0x090...0x0df	1-5	reserved
+		 * 0x0e0...0x0ff	6-7	8 entry ID table
+		 *				(mx25, mx28, mx35, mx53)
+		 * 0x0e0...0x2df	6-7..37	8..128 entry ID table
+		 *				size conf'ed via ctrl2::RFFN
+		 *				(mx6, vf610)
+		 */
+		u32 _reserved4[256];	/* 0x480 */
+		u32 rximr[64];		/* 0x880 - Not affected by Soft Reset */
+		u32 _reserved5[24];	/* 0x980 */
+		u32 gfwr_mx6;		/* 0x9e0 - MX6 */
+		u32 _reserved6[39];	/* 0x9e4 */
+		u32 _rxfir[6];		/* 0xa80 */
+		u32 _reserved8[2];	/* 0xa98 */
+		u32 _rxmgmask;		/* 0xaa0 */
+		u32 _rxfgmask;		/* 0xaa4 */
+		u32 _rx14mask;		/* 0xaa8 */
+		u32 _rx15mask;		/* 0xaac */
+		u32 tx_smb[4];		/* 0xab0 */
+		u32 rx_smb0[4];		/* 0xac0 */
+		u32 rx_smb1[4];		/* 0xad0 */
+	);
 	u32 mecr;		/* 0xae0 */
 	u32 erriar;		/* 0xae4 */
 	u32 erridpr;		/* 0xae8 */
@@ -328,9 +330,11 @@ struct flexcan_regs {
 	u32 fdcbt;		/* 0xc04 - Not affected by Soft Reset */
 	u32 fdcrc;		/* 0xc08 */
 	u32 _reserved9[199];	/* 0xc0c */
-	u32 tx_smb_fd[18];	/* 0xf28 */
-	u32 rx_smb0_fd[18];	/* 0xf70 */
-	u32 rx_smb1_fd[18];	/* 0xfb8 */
+	struct_group(init_fd,
+		u32 tx_smb_fd[18];	/* 0xf28 */
+		u32 rx_smb0_fd[18];	/* 0xf70 */
+		u32 rx_smb1_fd[18];	/* 0xfb8 */
+	);
 };
 
 static_assert(sizeof(struct flexcan_regs) ==  0x4 * 18 + 0xfb8);
@@ -1400,14 +1404,10 @@ static void flexcan_ram_init(struct net_device *dev)
 	reg_ctrl2 |= FLEXCAN_CTRL2_WRMFRZ;
 	priv->write(reg_ctrl2, &regs->ctrl2);
 
-	memset_io(&regs->mb[0][0], 0,
-		  offsetof(struct flexcan_regs, rx_smb1[3]) -
-		  offsetof(struct flexcan_regs, mb[0][0]) + 0x4);
+	memset_io(&regs->init, 0, sizeof(regs->init));
 
 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
-		memset_io(&regs->tx_smb_fd[0], 0,
-			  offsetof(struct flexcan_regs, rx_smb1_fd[17]) -
-			  offsetof(struct flexcan_regs, tx_smb_fd[0]) + 0x4);
+		memset_io(&regs->init_fd, 0, sizeof(regs->init_fd));
 
 	reg_ctrl2 &= ~FLEXCAN_CTRL2_WRMFRZ;
 	priv->write(reg_ctrl2, &regs->ctrl2);
diff --git a/drivers/net/can/usb/etas_es58x/es581_4.h b/drivers/net/can/usb/etas_es58x/es581_4.h
index 4bc60a6df697..667ecb77168c 100644
--- a/drivers/net/can/usb/etas_es58x/es581_4.h
+++ b/drivers/net/can/usb/etas_es58x/es581_4.h
@@ -192,7 +192,7 @@ struct es581_4_urb_cmd {
 		struct es581_4_rx_cmd_ret rx_cmd_ret;
 		__le64 timestamp;
 		u8 rx_cmd_ret_u8;
-		u8 raw_msg[0];
+		DECLARE_FLEX_ARRAY(u8, raw_msg);
 	} __packed;
 
 	__le16 reserved_for_crc16_do_not_use;
diff --git a/drivers/net/can/usb/etas_es58x/es58x_fd.h b/drivers/net/can/usb/etas_es58x/es58x_fd.h
index a191891b8777..c4b19a6a33ae 100644
--- a/drivers/net/can/usb/etas_es58x/es58x_fd.h
+++ b/drivers/net/can/usb/etas_es58x/es58x_fd.h
@@ -219,7 +219,7 @@ struct es58x_fd_urb_cmd {
 		struct es58x_fd_tx_ack_msg tx_ack_msg;
 		__le64 timestamp;
 		__le32 rx_cmd_ret_le32;
-		u8 raw_msg[0];
+		DECLARE_FLEX_ARRAY(u8, raw_msg);
 	} __packed;
 
 	__le16 reserved_for_crc16_do_not_use;
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.c
index 228a5db7e143..217ff597cdf2 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.c
@@ -159,10 +159,10 @@ static int bnxt_hwrm_queue_cos2bw_qcfg(struct bnxt *bp, struct ieee_ets *ets)
 	}
 
 	data = &resp->queue_id0 + offsetof(struct bnxt_cos2bw_cfg, queue_id);
-	for (i = 0; i < bp->max_tc; i++, data += sizeof(cos2bw) - 4) {
+	for (i = 0; i < bp->max_tc; i++, data += sizeof(cos2bw.cfg)) {
 		int tc;
 
-		memcpy(&cos2bw.queue_id, data, sizeof(cos2bw) - 4);
+		memcpy(&cos2bw.cfg, data, sizeof(cos2bw.cfg));
 		if (i == 0)
 			cos2bw.queue_id = resp->queue_id0;
 
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.h b/drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.h
index 6eed231de565..716742522161 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_dcb.h
@@ -23,13 +23,15 @@ struct bnxt_dcb {
 
 struct bnxt_cos2bw_cfg {
 	u8			pad[3];
-	u8			queue_id;
-	__le32			min_bw;
-	__le32			max_bw;
+	struct_group_attr(cfg, __packed,
+		u8		queue_id;
+		__le32		min_bw;
+		__le32		max_bw;
 #define BW_VALUE_UNIT_PERCENT1_100		(0x1UL << 29)
-	u8			tsa;
-	u8			pri_lvl;
-	u8			bw_weight;
+		u8		tsa;
+		u8		pri_lvl;
+		u8		bw_weight;
+	);
 	u8			unused;
 };
 
diff --git a/drivers/net/wireless/ath/ath10k/bmi.h b/drivers/net/wireless/ath/ath10k/bmi.h
index f6fadcbdd86e..0685c0d2d4ea 100644
--- a/drivers/net/wireless/ath/ath10k/bmi.h
+++ b/drivers/net/wireless/ath/ath10k/bmi.h
@@ -109,7 +109,7 @@ struct bmi_cmd {
 		struct {
 			__le32 addr;
 			__le32 len;
-			u8 payload[0];
+			u8 payload[];
 		} write_mem;
 		struct {
 			__le32 addr;
@@ -138,18 +138,18 @@ struct bmi_cmd {
 		} rompatch_uninstall;
 		struct {
 			__le32 count;
-			__le32 patch_ids[0]; /* length of @count */
+			__le32 patch_ids[]; /* length of @count */
 		} rompatch_activate;
 		struct {
 			__le32 count;
-			__le32 patch_ids[0]; /* length of @count */
+			__le32 patch_ids[]; /* length of @count */
 		} rompatch_deactivate;
 		struct {
 			__le32 addr;
 		} lz_start;
 		struct {
 			__le32 len; /* max BMI_MAX_DATA_SIZE */
-			u8 payload[0]; /* length of @len */
+			u8 payload[]; /* length of @len */
 		} lz_data;
 		struct {
 			u8 name[BMI_NVRAM_SEG_NAME_SZ];
@@ -160,7 +160,7 @@ struct bmi_cmd {
 
 union bmi_resp {
 	struct {
-		u8 payload[0];
+		DECLARE_FLEX_ARRAY(u8, payload);
 	} read_mem;
 	struct {
 		__le32 result;
diff --git a/drivers/net/wireless/ath/ath10k/htt.h b/drivers/net/wireless/ath/ath10k/htt.h
index ec689e3ce48a..a6de08d3bf4a 100644
--- a/drivers/net/wireless/ath/ath10k/htt.h
+++ b/drivers/net/wireless/ath/ath10k/htt.h
@@ -1674,8 +1674,11 @@ struct htt_tx_fetch_ind {
 	__le32 token;
 	__le16 num_resp_ids;
 	__le16 num_records;
-	__le32 resp_ids[0]; /* ath10k_htt_get_tx_fetch_ind_resp_ids() */
-	struct htt_tx_fetch_record records[];
+	union {
+		/* ath10k_htt_get_tx_fetch_ind_resp_ids() */
+		DECLARE_FLEX_ARRAY(__le32, resp_ids);
+		DECLARE_FLEX_ARRAY(struct htt_tx_fetch_record, records);
+	};
 } __packed;
 
 static inline void *
diff --git a/drivers/net/wireless/intel/iwlegacy/commands.h b/drivers/net/wireless/intel/iwlegacy/commands.h
index 89c6671b32bc..4a97310f8fee 100644
--- a/drivers/net/wireless/intel/iwlegacy/commands.h
+++ b/drivers/net/wireless/intel/iwlegacy/commands.h
@@ -1408,8 +1408,10 @@ struct il3945_tx_cmd {
 	 * MAC header goes here, followed by 2 bytes padding if MAC header
 	 * length is 26 or 30 bytes, followed by payload data
 	 */
-	u8 payload[0];
-	struct ieee80211_hdr hdr[];
+	union {
+		DECLARE_FLEX_ARRAY(u8, payload);
+		DECLARE_FLEX_ARRAY(struct ieee80211_hdr, hdr);
+	};
 } __packed;
 
 /*
diff --git a/drivers/net/wireless/intel/iwlwifi/dvm/commands.h b/drivers/net/wireless/intel/iwlwifi/dvm/commands.h
index 235c7a2e3483..75a4b8e26232 100644
--- a/drivers/net/wireless/intel/iwlwifi/dvm/commands.h
+++ b/drivers/net/wireless/intel/iwlwifi/dvm/commands.h
@@ -1251,8 +1251,10 @@ struct iwl_tx_cmd {
 	 * MAC header goes here, followed by 2 bytes padding if MAC header
 	 * length is 26 or 30 bytes, followed by payload data
 	 */
-	u8 payload[0];
-	struct ieee80211_hdr hdr[];
+	union {
+		DECLARE_FLEX_ARRAY(u8, payload);
+		DECLARE_FLEX_ARRAY(struct ieee80211_hdr, hdr);
+	};
 } __packed;
 
 /*
diff --git a/drivers/net/wireless/intel/iwlwifi/fw/api/tx.h b/drivers/net/wireless/intel/iwlwifi/fw/api/tx.h
index 24e4a82a55da..5fddfd391941 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/api/tx.h
+++ b/drivers/net/wireless/intel/iwlwifi/fw/api/tx.h
@@ -239,8 +239,10 @@ struct iwl_tx_cmd {
 	u8 tid_tspec;
 	__le16 pm_frame_timeout;
 	__le16 reserved4;
-	u8 payload[0];
-	struct ieee80211_hdr hdr[0];
+	union {
+		DECLARE_FLEX_ARRAY(u8, payload);
+		DECLARE_FLEX_ARRAY(struct ieee80211_hdr, hdr);
+	};
 } __packed; /* TX_CMD_API_S_VER_6 */
 
 struct iwl_dram_sec_info {
@@ -713,8 +715,10 @@ struct iwl_mvm_compressed_ba_notif {
 	__le32 tx_rate;
 	__le16 tfd_cnt;
 	__le16 ra_tid_cnt;
-	struct iwl_mvm_compressed_ba_ratid ra_tid[0];
-	struct iwl_mvm_compressed_ba_tfd tfd[];
+	union {
+		DECLARE_FLEX_ARRAY(struct iwl_mvm_compressed_ba_ratid, ra_tid);
+		DECLARE_FLEX_ARRAY(struct iwl_mvm_compressed_ba_tfd, tfd);
+	};
 } __packed; /* COMPRESSED_BA_RES_API_S_VER_4 */
 
 /**
diff --git a/drivers/scsi/aic94xx/aic94xx_sds.c b/drivers/scsi/aic94xx/aic94xx_sds.c
index 46815e65f7a4..5def83c88f13 100644
--- a/drivers/scsi/aic94xx/aic94xx_sds.c
+++ b/drivers/scsi/aic94xx/aic94xx_sds.c
@@ -517,8 +517,10 @@ struct asd_ms_conn_map {
 	u8    num_nodes;
 	u8    usage_model_id;
 	u32   _resvd;
-	struct asd_ms_conn_desc conn_desc[0];
-	struct asd_ms_node_desc node_desc[];
+	union {
+		DECLARE_FLEX_ARRAY(struct asd_ms_conn_desc, conn_desc);
+		DECLARE_FLEX_ARRAY(struct asd_ms_node_desc, node_desc);
+	};
 } __attribute__ ((packed));
 
 struct asd_ctrla_phy_entry {
diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index 50df7dd9cb91..ea8e01f49cba 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -1055,8 +1055,9 @@ static int ibmvscsi_queuecommand_lck(struct scsi_cmnd *cmnd,
 		return SCSI_MLQUEUE_HOST_BUSY;
 
 	/* Set up the actual SRP IU */
+	BUILD_BUG_ON(sizeof(evt_struct->iu.srp) != SRP_MAX_IU_LEN);
+	memset(&evt_struct->iu.srp, 0x00, sizeof(evt_struct->iu.srp));
 	srp_cmd = &evt_struct->iu.srp.cmd;
-	memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
 	srp_cmd->opcode = SRP_CMD;
 	memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(srp_cmd->cdb));
 	int_to_scsilun(lun, &srp_cmd->lun);
diff --git a/drivers/scsi/qla4xxx/ql4_def.h b/drivers/scsi/qla4xxx/ql4_def.h
index 031569c496e5..69a590546bf9 100644
--- a/drivers/scsi/qla4xxx/ql4_def.h
+++ b/drivers/scsi/qla4xxx/ql4_def.h
@@ -366,13 +366,13 @@ struct qla4_work_evt {
 		struct {
 			enum iscsi_host_event_code code;
 			uint32_t data_size;
-			uint8_t data[0];
+			uint8_t data[];
 		} aen;
 		struct {
 			uint32_t status;
 			uint32_t pid;
 			uint32_t data_size;
-			uint8_t data[0];
+			uint8_t data[];
 		} ping;
 	} u;
 };
diff --git a/drivers/staging/r8188eu/include/ieee80211.h b/drivers/staging/r8188eu/include/ieee80211.h
index bc5b030e9c40..9204dd42f319 100644
--- a/drivers/staging/r8188eu/include/ieee80211.h
+++ b/drivers/staging/r8188eu/include/ieee80211.h
@@ -185,7 +185,7 @@ struct ieee_param {
 		struct {
 			u32 len;
 			u8 reserved[32];
-			u8 data[0];
+			u8 data[];
 		} wpa_ie;
 		struct {
 			int command;
@@ -198,7 +198,7 @@ struct ieee_param {
 			u8 idx;
 			u8 seq[8]; /* sequence counter (set: RX, get: TX) */
 			u16 key_len;
-			u8 key[0];
+			u8 key[];
 		} crypt;
 #ifdef CONFIG_88EU_AP_MODE
 		struct {
@@ -210,7 +210,7 @@ struct ieee_param {
 		} add_sta;
 		struct {
 			u8	reserved[2];/* for set max_num_sta */
-			u8	buf[0];
+			u8	buf[];
 		} bcn_ie;
 #endif
 
diff --git a/drivers/staging/rtl8712/ieee80211.h b/drivers/staging/rtl8712/ieee80211.h
index 61eff7c5746b..65ceaca9b51e 100644
--- a/drivers/staging/rtl8712/ieee80211.h
+++ b/drivers/staging/rtl8712/ieee80211.h
@@ -78,7 +78,7 @@ struct ieee_param {
 		struct {
 			u32 len;
 			u8 reserved[32];
-			u8 data[0];
+			u8 data[];
 		} wpa_ie;
 		struct {
 			int command;
@@ -91,7 +91,7 @@ struct ieee_param {
 			u8 idx;
 			u8 seq[8]; /* sequence counter (set: RX, get: TX) */
 			u16 key_len;
-			u8 key[0];
+			u8 key[];
 		} crypt;
 	} u;
 };
diff --git a/drivers/staging/rtl8723bs/include/ieee80211.h b/drivers/staging/rtl8723bs/include/ieee80211.h
index d6236f5b069d..c11d7e2d2347 100644
--- a/drivers/staging/rtl8723bs/include/ieee80211.h
+++ b/drivers/staging/rtl8723bs/include/ieee80211.h
@@ -172,7 +172,7 @@ struct ieee_param {
 		struct {
 			u32 len;
 			u8 reserved[32];
-			u8 data[0];
+			u8 data[];
 		} wpa_ie;
 	        struct{
 			int command;
@@ -185,7 +185,7 @@ struct ieee_param {
 			u8 idx;
 			u8 seq[8]; /* sequence counter (set: RX, get: TX) */
 			u16 key_len;
-			u8 key[0];
+			u8 key[];
 		} crypt;
 		struct {
 			u16 aid;
@@ -196,7 +196,7 @@ struct ieee_param {
 		} add_sta;
 		struct {
 			u8 reserved[2];/* for set max_num_sta */
-			u8 buf[0];
+			u8 buf[];
 		} bcn_ie;
 	} u;
 };