diff --git a/drivers/staging/lustre/include/linux/libcfs/libcfs_ioctl.h b/drivers/staging/lustre/include/linux/libcfs/libcfs_ioctl.h
index e4463ada0343..0598702367b5 100644
--- a/drivers/staging/lustre/include/linux/libcfs/libcfs_ioctl.h
+++ b/drivers/staging/lustre/include/linux/libcfs/libcfs_ioctl.h
@@ -43,9 +43,13 @@
 
 #define LIBCFS_IOCTL_VERSION 0x0001000a
 
-struct libcfs_ioctl_data {
+struct libcfs_ioctl_hdr {
 	__u32 ioc_len;
 	__u32 ioc_version;
+};
+
+struct libcfs_ioctl_data {
+	struct libcfs_ioctl_hdr ioc_hdr;
 
 	__u64 ioc_nid;
 	__u64 ioc_u64[1];
@@ -70,11 +74,6 @@ struct libcfs_ioctl_data {
 
 #define ioc_priority ioc_u32[0]
 
-struct libcfs_ioctl_hdr {
-	__u32 ioc_len;
-	__u32 ioc_version;
-};
-
 struct libcfs_debug_ioctl_data {
 	struct libcfs_ioctl_hdr hdr;
 	unsigned int subs;
@@ -90,7 +89,7 @@ do {						    \
 
 struct libcfs_ioctl_handler {
 	struct list_head item;
-	int (*handle_ioctl)(unsigned int cmd, struct libcfs_ioctl_data *data);
+	int (*handle_ioctl)(unsigned int cmd, struct libcfs_ioctl_hdr *hdr);
 };
 
 #define DECLARE_IOCTL_HANDLER(ident, func)		      \
@@ -148,9 +147,9 @@ static inline int libcfs_ioctl_packlen(struct libcfs_ioctl_data *data)
 	return len;
 }
 
-static inline int libcfs_ioctl_is_invalid(struct libcfs_ioctl_data *data)
+static inline bool libcfs_ioctl_is_invalid(struct libcfs_ioctl_data *data)
 {
-	if (data->ioc_len > (1<<30)) {
+	if (data->ioc_hdr.ioc_len > (1 << 30)) {
 		CERROR("LIBCFS ioctl: ioc_len larger than 1<<30\n");
 		return 1;
 	}
@@ -186,7 +185,7 @@ static inline int libcfs_ioctl_is_invalid(struct libcfs_ioctl_data *data)
 		CERROR("LIBCFS ioctl: plen2 nonzero but no pbuf2 pointer\n");
 		return 1;
 	}
-	if ((__u32)libcfs_ioctl_packlen(data) != data->ioc_len) {
+	if ((__u32)libcfs_ioctl_packlen(data) != data->ioc_hdr.ioc_len) {
 		CERROR("LIBCFS ioctl: packlen != ioc_len\n");
 		return 1;
 	}
@@ -206,7 +205,9 @@ static inline int libcfs_ioctl_is_invalid(struct libcfs_ioctl_data *data)
 
 int libcfs_register_ioctl(struct libcfs_ioctl_handler *hand);
 int libcfs_deregister_ioctl(struct libcfs_ioctl_handler *hand);
-int libcfs_ioctl_getdata(char *buf, char *end, void __user *arg);
+int libcfs_ioctl_getdata_len(const struct libcfs_ioctl_hdr __user *arg,
+			     __u32 *buf_len);
 int libcfs_ioctl_popdata(void __user *arg, void *buf, int size);
+int libcfs_ioctl_data_adjust(struct libcfs_ioctl_data *data);
 
 #endif /* __LIBCFS_IOCTL_H__ */
diff --git a/drivers/staging/lustre/lnet/lnet/module.c b/drivers/staging/lustre/lnet/lnet/module.c
index cd3730328117..46f5241a6e82 100644
--- a/drivers/staging/lustre/lnet/lnet/module.c
+++ b/drivers/staging/lustre/lnet/lnet/module.c
@@ -84,7 +84,7 @@ lnet_unconfigure(void)
 }
 
 static int
-lnet_ioctl(unsigned int cmd, struct libcfs_ioctl_data *data)
+lnet_ioctl(unsigned int cmd, struct libcfs_ioctl_hdr *hdr)
 {
 	int rc;
 
@@ -103,7 +103,7 @@ lnet_ioctl(unsigned int cmd, struct libcfs_ioctl_data *data)
 		 */
 		rc = LNetNIInit(LNET_PID_ANY);
 		if (rc >= 0) {
-			rc = LNetCtl(cmd, data);
+			rc = LNetCtl(cmd, hdr);
 			LNetNIFini();
 		}
 		return rc;
diff --git a/drivers/staging/lustre/lnet/selftest/conctl.c b/drivers/staging/lustre/lnet/selftest/conctl.c
index 210e24e6db0d..90b7771ac7c6 100644
--- a/drivers/staging/lustre/lnet/selftest/conctl.c
+++ b/drivers/staging/lustre/lnet/selftest/conctl.c
@@ -801,15 +801,20 @@ out:
 }
 
 int
-lstcon_ioctl_entry(unsigned int cmd, struct libcfs_ioctl_data *data)
+lstcon_ioctl_entry(unsigned int cmd, struct libcfs_ioctl_hdr *hdr)
 {
 	char   *buf;
-	int     opc = data->ioc_u32[0];
+	struct libcfs_ioctl_data *data;
+	int     opc;
 	int     rc;
 
 	if (cmd != IOC_LIBCFS_LNETST)
 		return -EINVAL;
 
+	data = container_of(hdr, struct libcfs_ioctl_data, ioc_hdr);
+
+	opc = data->ioc_u32[0];
+
 	if (data->ioc_plen1 > PAGE_CACHE_SIZE)
 		return -EINVAL;
 
diff --git a/drivers/staging/lustre/lnet/selftest/console.c b/drivers/staging/lustre/lnet/selftest/console.c
index 1385dc0baef9..badc6965f5ed 100644
--- a/drivers/staging/lustre/lnet/selftest/console.c
+++ b/drivers/staging/lustre/lnet/selftest/console.c
@@ -1983,7 +1983,7 @@ static void lstcon_init_acceptor_service(void)
 	lstcon_acceptor_service.sv_wi_total = SFW_FRWK_WI_MAX;
 }
 
-extern int lstcon_ioctl_entry(unsigned int cmd, struct libcfs_ioctl_data *data);
+extern int lstcon_ioctl_entry(unsigned int cmd, struct libcfs_ioctl_hdr *hdr);
 
 static DECLARE_IOCTL_HANDLER(lstcon_ioctl_handler, lstcon_ioctl_entry);
 
diff --git a/drivers/staging/lustre/lnet/selftest/console.h b/drivers/staging/lustre/lnet/selftest/console.h
index b7e14e4a1f70..c9d1081d9f38 100644
--- a/drivers/staging/lustre/lnet/selftest/console.h
+++ b/drivers/staging/lustre/lnet/selftest/console.h
@@ -184,7 +184,6 @@ lstcon_id2hash(lnet_process_id_t id, struct list_head *hash)
 }
 
 int lstcon_console_init(void);
-int lstcon_ioctl_entry(unsigned int cmd, struct libcfs_ioctl_data *data);
 int lstcon_console_fini(void);
 int lstcon_session_match(lst_sid_t sid);
 int lstcon_session_new(char *name, int key, unsigned version,
diff --git a/drivers/staging/lustre/lustre/libcfs/linux/linux-module.c b/drivers/staging/lustre/lustre/libcfs/linux/linux-module.c
index ff9077249716..f62c5bcd3d1b 100644
--- a/drivers/staging/lustre/lustre/libcfs/linux/linux-module.c
+++ b/drivers/staging/lustre/lustre/libcfs/linux/linux-module.c
@@ -40,41 +40,10 @@
 
 #define LNET_MINOR 240
 
-int libcfs_ioctl_getdata(char *buf, char *end, void __user *arg)
+int libcfs_ioctl_data_adjust(struct libcfs_ioctl_data *data)
 {
-	struct libcfs_ioctl_hdr   *hdr;
-	struct libcfs_ioctl_data  *data;
-	int orig_len;
-
-	hdr = (struct libcfs_ioctl_hdr *)buf;
-	data = (struct libcfs_ioctl_data *)buf;
-
-	if (copy_from_user(buf, arg, sizeof(*hdr)))
-		return -EFAULT;
-
-	if (hdr->ioc_version != LIBCFS_IOCTL_VERSION) {
-		CERROR("PORTALS: version mismatch kernel vs application\n");
-		return -EINVAL;
-	}
-
-	if (hdr->ioc_len >= end - buf) {
-		CERROR("PORTALS: user buffer exceeds kernel buffer\n");
-		return -EINVAL;
-	}
-
-	if (hdr->ioc_len < sizeof(struct libcfs_ioctl_data)) {
-		CERROR("PORTALS: user buffer too small for ioctl\n");
-		return -EINVAL;
-	}
-
-	orig_len = hdr->ioc_len;
-	if (copy_from_user(buf, arg, hdr->ioc_len))
-		return -EFAULT;
-	if (orig_len != data->ioc_len)
-		return -EINVAL;
-
 	if (libcfs_ioctl_is_invalid(data)) {
-		CERROR("PORTALS: ioctl not correctly formatted\n");
+		CERROR("LNET: ioctl not correctly formatted\n");
 		return -EINVAL;
 	}
 
@@ -88,6 +57,25 @@ int libcfs_ioctl_getdata(char *buf, char *end, void __user *arg)
 	return 0;
 }
 
+int libcfs_ioctl_getdata_len(const struct libcfs_ioctl_hdr __user *arg,
+			     __u32 *len)
+{
+	struct libcfs_ioctl_hdr hdr;
+
+	if (copy_from_user(&hdr, arg, sizeof(hdr)))
+		return -EFAULT;
+
+	if (hdr.ioc_version != LIBCFS_IOCTL_VERSION) {
+		CERROR("LNET: version mismatch expected %#x, got %#x\n",
+		       LIBCFS_IOCTL_VERSION, hdr.ioc_version);
+		return -EINVAL;
+	}
+
+	*len = hdr.ioc_len;
+
+	return 0;
+}
+
 int libcfs_ioctl_popdata(void __user *arg, void *data, int size)
 {
 	if (copy_to_user(arg, data, size))
diff --git a/drivers/staging/lustre/lustre/libcfs/module.c b/drivers/staging/lustre/lustre/libcfs/module.c
index ea3dc9bdc99b..1cb6c80b9f50 100644
--- a/drivers/staging/lustre/lustre/libcfs/module.c
+++ b/drivers/staging/lustre/lustre/libcfs/module.c
@@ -54,6 +54,8 @@
 
 # define DEBUG_SUBSYSTEM S_LNET
 
+#define LIBCFS_MAX_IOCTL_BUF_LEN 2048
+
 #include "../../include/linux/libcfs/libcfs.h"
 #include <asm/div64.h>
 
@@ -115,11 +117,20 @@ int libcfs_deregister_ioctl(struct libcfs_ioctl_handler *hand)
 }
 EXPORT_SYMBOL(libcfs_deregister_ioctl);
 
-static int libcfs_ioctl_int(struct cfs_psdev_file *pfile, unsigned long cmd,
-			    void __user *arg, struct libcfs_ioctl_data *data)
+static int libcfs_ioctl_handle(struct cfs_psdev_file *pfile, unsigned long cmd,
+			       void *arg, struct libcfs_ioctl_hdr *hdr)
 {
+	struct libcfs_ioctl_data *data = NULL;
 	int err = -EINVAL;
 
+	if ((cmd <= IOC_LIBCFS_LNETST) ||
+	    (cmd >= IOC_LIBCFS_REGISTER_MYNID)) {
+		data = container_of(hdr, struct libcfs_ioctl_data, ioc_hdr);
+		err = libcfs_ioctl_data_adjust(data);
+		if (err)
+			return err;
+	}
+
 	switch (cmd) {
 	case IOC_LIBCFS_CLEAR_DEBUG:
 		libcfs_debug_clear_buffer();
@@ -141,11 +152,11 @@ static int libcfs_ioctl_int(struct cfs_psdev_file *pfile, unsigned long cmd,
 		err = -EINVAL;
 		down_read(&ioctl_list_sem);
 		list_for_each_entry(hand, &ioctl_list, item) {
-			err = hand->handle_ioctl(cmd, data);
+			err = hand->handle_ioctl(cmd, hdr);
 			if (err != -EINVAL) {
 				if (err == 0)
 					err = libcfs_ioctl_popdata(arg,
-							data, sizeof(*data));
+							hdr, hdr->ioc_len);
 				break;
 			}
 		}
@@ -160,26 +171,38 @@ static int libcfs_ioctl_int(struct cfs_psdev_file *pfile, unsigned long cmd,
 static int libcfs_ioctl(struct cfs_psdev_file *pfile, unsigned long cmd,
 			void __user *arg)
 {
-	char    *buf;
-	struct libcfs_ioctl_data *data;
+	struct libcfs_ioctl_hdr *hdr;
 	int err = 0;
+	__u32 buf_len;
 
-	LIBCFS_ALLOC_GFP(buf, 1024, GFP_KERNEL);
-	if (!buf)
+	err = libcfs_ioctl_getdata_len(arg, &buf_len);
+	if (err)
+		return err;
+
+	/*
+	 * do a check here to restrict the size of the memory
+	 * to allocate to guard against DoS attacks.
+	 */
+	if (buf_len > LIBCFS_MAX_IOCTL_BUF_LEN) {
+		CERROR("LNET: user buffer exceeds kernel buffer\n");
+		return -EINVAL;
+	}
+
+	LIBCFS_ALLOC_GFP(hdr, buf_len, GFP_KERNEL);
+	if (!hdr)
 		return -ENOMEM;
 
 	/* 'cmd' and permissions get checked in our arch-specific caller */
-	if (libcfs_ioctl_getdata(buf, buf + 800, arg)) {
-		CERROR("PORTALS ioctl: data error\n");
-		err = -EINVAL;
+	if (copy_from_user(hdr, arg, buf_len)) {
+		CERROR("LNET ioctl: data error\n");
+		err = -EFAULT;
 		goto out;
 	}
-	data = (struct libcfs_ioctl_data *)buf;
 
-	err = libcfs_ioctl_int(pfile, cmd, arg, data);
+	err = libcfs_ioctl_handle(pfile, cmd, arg, hdr);
 
 out:
-	LIBCFS_FREE(buf, 1024);
+	LIBCFS_FREE(hdr, buf_len);
 	return err;
 }