diff --git a/arch/powerpc/include/asm/systbl.h b/arch/powerpc/include/asm/systbl.h
index fa0d27a400de917ee45a7a85dd75c2dbbaabb745..559ae1ee67061ca08ccbd69c24aa60e1019dc1a1 100644
--- a/arch/powerpc/include/asm/systbl.h
+++ b/arch/powerpc/include/asm/systbl.h
@@ -354,3 +354,5 @@ COMPAT_SYS_SPU(clock_adjtime)
 SYSCALL_SPU(syncfs)
 COMPAT_SYS_SPU(sendmmsg)
 SYSCALL_SPU(setns)
+COMPAT_SYS(process_vm_readv)
+COMPAT_SYS(process_vm_writev)
diff --git a/arch/powerpc/include/asm/unistd.h b/arch/powerpc/include/asm/unistd.h
index b8b3f599362b70167ab8db7c49038ad08f2b02f2..d3d1b5efd7eb1204405fde26c701e7c52b925fd9 100644
--- a/arch/powerpc/include/asm/unistd.h
+++ b/arch/powerpc/include/asm/unistd.h
@@ -373,10 +373,12 @@
 #define __NR_syncfs		348
 #define __NR_sendmmsg		349
 #define __NR_setns		350
+#define __NR_process_vm_readv	351
+#define __NR_process_vm_writev	352
 
 #ifdef __KERNEL__
 
-#define __NR_syscalls		351
+#define __NR_syscalls		353
 
 #define __NR__exit __NR_exit
 #define NR_syscalls	__NR_syscalls
diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
index 54edb207ff3a0cb181811219cdc46500c8ba66d5..a6253ec1b28461e12d6f650683c6d05c99a7a7cc 100644
--- a/arch/x86/ia32/ia32entry.S
+++ b/arch/x86/ia32/ia32entry.S
@@ -850,4 +850,6 @@ ia32_sys_call_table:
 	.quad sys_syncfs
 	.quad compat_sys_sendmmsg	/* 345 */
 	.quad sys_setns
+	.quad compat_sys_process_vm_readv
+	.quad compat_sys_process_vm_writev
 ia32_syscall_end:
diff --git a/arch/x86/include/asm/unistd_32.h b/arch/x86/include/asm/unistd_32.h
index 593485b38ab38cc501e3f975209aabfb3f710106..599c77d38f332f06fdf1e34f7449e2b7b5c81203 100644
--- a/arch/x86/include/asm/unistd_32.h
+++ b/arch/x86/include/asm/unistd_32.h
@@ -352,10 +352,12 @@
 #define __NR_syncfs             344
 #define __NR_sendmmsg		345
 #define __NR_setns		346
+#define __NR_process_vm_readv	347
+#define __NR_process_vm_writev	348
 
 #ifdef __KERNEL__
 
-#define NR_syscalls 347
+#define NR_syscalls 349
 
 #define __ARCH_WANT_IPC_PARSE_VERSION
 #define __ARCH_WANT_OLD_READDIR
diff --git a/arch/x86/include/asm/unistd_64.h b/arch/x86/include/asm/unistd_64.h
index 0a6ba337a2eb7922f60ef2293d76aced631b3f5c..0431f193c3f29f4f3cdb7fce9d84ca3d23b92571 100644
--- a/arch/x86/include/asm/unistd_64.h
+++ b/arch/x86/include/asm/unistd_64.h
@@ -682,6 +682,10 @@ __SYSCALL(__NR_sendmmsg, sys_sendmmsg)
 __SYSCALL(__NR_setns, sys_setns)
 #define __NR_getcpu				309
 __SYSCALL(__NR_getcpu, sys_getcpu)
+#define __NR_process_vm_readv			310
+__SYSCALL(__NR_process_vm_readv, sys_process_vm_readv)
+#define __NR_process_vm_writev			311
+__SYSCALL(__NR_process_vm_writev, sys_process_vm_writev)
 
 #ifndef __NO_STUBS
 #define __ARCH_WANT_OLD_READDIR
diff --git a/arch/x86/kernel/syscall_table_32.S b/arch/x86/kernel/syscall_table_32.S
index bc19be332bc99544ccbe426975b8b0cdb136f293..9a0e31293920a51568b8ec6e6d3b204cfa0b98a1 100644
--- a/arch/x86/kernel/syscall_table_32.S
+++ b/arch/x86/kernel/syscall_table_32.S
@@ -346,3 +346,5 @@ ENTRY(sys_call_table)
 	.long sys_syncfs
 	.long sys_sendmmsg		/* 345 */
 	.long sys_setns
+	.long sys_process_vm_readv
+	.long sys_process_vm_writev
diff --git a/fs/aio.c b/fs/aio.c
index e29ec485af255822b8414be128fc8ef66da9a204..632b235f4fbe02c237de17fbde271c8bfe6f1240 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1387,13 +1387,13 @@ static ssize_t aio_setup_vectored_rw(int type, struct kiocb *kiocb, bool compat)
 		ret = compat_rw_copy_check_uvector(type,
 				(struct compat_iovec __user *)kiocb->ki_buf,
 				kiocb->ki_nbytes, 1, &kiocb->ki_inline_vec,
-				&kiocb->ki_iovec);
+				&kiocb->ki_iovec, 1);
 	else
 #endif
 		ret = rw_copy_check_uvector(type,
 				(struct iovec __user *)kiocb->ki_buf,
 				kiocb->ki_nbytes, 1, &kiocb->ki_inline_vec,
-				&kiocb->ki_iovec);
+				&kiocb->ki_iovec, 1);
 	if (ret < 0)
 		goto out;
 
diff --git a/fs/compat.c b/fs/compat.c
index 302e761bd0aa643712c4626424d4d708919017e0..c98787536bb888969c37afed2f0a5c5409098682 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -546,7 +546,7 @@ compat_sys_io_getevents(aio_context_t ctx_id,
 ssize_t compat_rw_copy_check_uvector(int type,
 		const struct compat_iovec __user *uvector, unsigned long nr_segs,
 		unsigned long fast_segs, struct iovec *fast_pointer,
-		struct iovec **ret_pointer)
+		struct iovec **ret_pointer, int check_access)
 {
 	compat_ssize_t tot_len;
 	struct iovec *iov = *ret_pointer = fast_pointer;
@@ -593,7 +593,8 @@ ssize_t compat_rw_copy_check_uvector(int type,
 		}
 		if (len < 0)	/* size_t not fitting in compat_ssize_t .. */
 			goto out;
-		if (!access_ok(vrfy_dir(type), compat_ptr(buf), len)) {
+		if (check_access &&
+		    !access_ok(vrfy_dir(type), compat_ptr(buf), len)) {
 			ret = -EFAULT;
 			goto out;
 		}
@@ -1107,7 +1108,7 @@ static ssize_t compat_do_readv_writev(int type, struct file *file,
 		goto out;
 
 	tot_len = compat_rw_copy_check_uvector(type, uvector, nr_segs,
-					       UIO_FASTIOV, iovstack, &iov);
+					       UIO_FASTIOV, iovstack, &iov, 1);
 	if (tot_len == 0) {
 		ret = 0;
 		goto out;
diff --git a/fs/read_write.c b/fs/read_write.c
index dfd125798791161c6c1cea427a791522169902ce..5ad4248b0cd8f00e545ac68d477566a9ea12fdc1 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -633,7 +633,8 @@ ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov,
 ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
 			      unsigned long nr_segs, unsigned long fast_segs,
 			      struct iovec *fast_pointer,
-			      struct iovec **ret_pointer)
+			      struct iovec **ret_pointer,
+			      int check_access)
 {
 	unsigned long seg;
 	ssize_t ret;
@@ -689,7 +690,8 @@ ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
 			ret = -EINVAL;
 			goto out;
 		}
-		if (unlikely(!access_ok(vrfy_dir(type), buf, len))) {
+		if (check_access
+		    && unlikely(!access_ok(vrfy_dir(type), buf, len))) {
 			ret = -EFAULT;
 			goto out;
 		}
@@ -721,7 +723,7 @@ static ssize_t do_readv_writev(int type, struct file *file,
 	}
 
 	ret = rw_copy_check_uvector(type, uvector, nr_segs,
-			ARRAY_SIZE(iovstack), iovstack, &iov);
+				    ARRAY_SIZE(iovstack), iovstack, &iov, 1);
 	if (ret <= 0)
 		goto out;
 
diff --git a/include/linux/compat.h b/include/linux/compat.h
index c6e7523bf7652ab050285c2c02dad3715a010cab..154bf56830156876d56c1ced7d4c1e6c96973805 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -547,7 +547,8 @@ extern ssize_t compat_rw_copy_check_uvector(int type,
 		const struct compat_iovec __user *uvector,
 		unsigned long nr_segs,
 		unsigned long fast_segs, struct iovec *fast_pointer,
-		struct iovec **ret_pointer);
+		struct iovec **ret_pointer,
+		int check_access);
 
 extern void __user *compat_alloc_user_space(unsigned long len);
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 14493a2d5a0360452dab19c01ba5ebc8605359e8..87b4c6b9692ddc7acc959102d36997ccb94a358b 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1633,9 +1633,10 @@ struct inode_operations {
 struct seq_file;
 
 ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
-				unsigned long nr_segs, unsigned long fast_segs,
-				struct iovec *fast_pointer,
-				struct iovec **ret_pointer);
+			      unsigned long nr_segs, unsigned long fast_segs,
+			      struct iovec *fast_pointer,
+			      struct iovec **ret_pointer,
+			      int check_access);
 
 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 1ff0ec2a5e8d29a2a4519bb882900c56f39c0dab..86a24b1166d16d28bb49f44bd0317cff51fb1ff8 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -844,4 +844,17 @@ asmlinkage long sys_open_by_handle_at(int mountdirfd,
 				      struct file_handle __user *handle,
 				      int flags);
 asmlinkage long sys_setns(int fd, int nstype);
+asmlinkage long sys_process_vm_readv(pid_t pid,
+				     const struct iovec __user *lvec,
+				     unsigned long liovcnt,
+				     const struct iovec __user *rvec,
+				     unsigned long riovcnt,
+				     unsigned long flags);
+asmlinkage long sys_process_vm_writev(pid_t pid,
+				      const struct iovec __user *lvec,
+				      unsigned long liovcnt,
+				      const struct iovec __user *rvec,
+				      unsigned long riovcnt,
+				      unsigned long flags);
+
 #endif
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index a9a5de07c4f16e1310616cb9dd51903f710199ff..47bfa16430d7dc764c17a06f4c40dd142ef6a88a 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -145,6 +145,10 @@ cond_syscall(sys_io_submit);
 cond_syscall(sys_io_cancel);
 cond_syscall(sys_io_getevents);
 cond_syscall(sys_syslog);
+cond_syscall(sys_process_vm_readv);
+cond_syscall(sys_process_vm_writev);
+cond_syscall(compat_sys_process_vm_readv);
+cond_syscall(compat_sys_process_vm_writev);
 
 /* arch-specific weak syscall entries */
 cond_syscall(sys_pciconfig_read);
diff --git a/mm/Makefile b/mm/Makefile
index 836e4163c1bfd91c5742c9f5227fc105d79a3b76..50ec00ef2a0e85a11ef8202529b405b069702a8d 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -5,7 +5,8 @@
 mmu-y			:= nommu.o
 mmu-$(CONFIG_MMU)	:= fremap.o highmem.o madvise.o memory.o mincore.o \
 			   mlock.o mmap.o mprotect.o mremap.o msync.o rmap.o \
-			   vmalloc.o pagewalk.o pgtable-generic.o
+			   vmalloc.o pagewalk.o pgtable-generic.o \
+			   process_vm_access.o
 
 obj-y			:= filemap.o mempool.o oom_kill.o fadvise.o \
 			   maccess.o page_alloc.o page-writeback.o \
diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c
new file mode 100644
index 0000000000000000000000000000000000000000..e920aa3ce104c35b902e8412864c78102fa3177e
--- /dev/null
+++ b/mm/process_vm_access.c
@@ -0,0 +1,496 @@
+/*
+ * linux/mm/process_vm_access.c
+ *
+ * Copyright (C) 2010-2011 Christopher Yeoh <cyeoh@au1.ibm.com>, IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/mm.h>
+#include <linux/uio.h>
+#include <linux/sched.h>
+#include <linux/highmem.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/syscalls.h>
+
+#ifdef CONFIG_COMPAT
+#include <linux/compat.h>
+#endif
+
+/**
+ * process_vm_rw_pages - read/write pages from task specified
+ * @task: task to read/write from
+ * @mm: mm for task
+ * @process_pages: struct pages area that can store at least
+ *  nr_pages_to_copy struct page pointers
+ * @pa: address of page in task to start copying from/to
+ * @start_offset: offset in page to start copying from/to
+ * @len: number of bytes to copy
+ * @lvec: iovec array specifying where to copy to/from
+ * @lvec_cnt: number of elements in iovec array
+ * @lvec_current: index in iovec array we are up to
+ * @lvec_offset: offset in bytes from current iovec iov_base we are up to
+ * @vm_write: 0 means copy from, 1 means copy to
+ * @nr_pages_to_copy: number of pages to copy
+ * @bytes_copied: returns number of bytes successfully copied
+ * Returns 0 on success, error code otherwise
+ */
+static int process_vm_rw_pages(struct task_struct *task,
+			       struct mm_struct *mm,
+			       struct page **process_pages,
+			       unsigned long pa,
+			       unsigned long start_offset,
+			       unsigned long len,
+			       const struct iovec *lvec,
+			       unsigned long lvec_cnt,
+			       unsigned long *lvec_current,
+			       size_t *lvec_offset,
+			       int vm_write,
+			       unsigned int nr_pages_to_copy,
+			       ssize_t *bytes_copied)
+{
+	int pages_pinned;
+	void *target_kaddr;
+	int pgs_copied = 0;
+	int j;
+	int ret;
+	ssize_t bytes_to_copy;
+	ssize_t rc = 0;
+
+	*bytes_copied = 0;
+
+	/* Get the pages we're interested in */
+	down_read(&mm->mmap_sem);
+	pages_pinned = get_user_pages(task, mm, pa,
+				      nr_pages_to_copy,
+				      vm_write, 0, process_pages, NULL);
+	up_read(&mm->mmap_sem);
+
+	if (pages_pinned != nr_pages_to_copy) {
+		rc = -EFAULT;
+		goto end;
+	}
+
+	/* Do the copy for each page */
+	for (pgs_copied = 0;
+	     (pgs_copied < nr_pages_to_copy) && (*lvec_current < lvec_cnt);
+	     pgs_copied++) {
+		/* Make sure we have a non zero length iovec */
+		while (*lvec_current < lvec_cnt
+		       && lvec[*lvec_current].iov_len == 0)
+			(*lvec_current)++;
+		if (*lvec_current == lvec_cnt)
+			break;
+
+		/*
+		 * Will copy smallest of:
+		 * - bytes remaining in page
+		 * - bytes remaining in destination iovec
+		 */
+		bytes_to_copy = min_t(ssize_t, PAGE_SIZE - start_offset,
+				      len - *bytes_copied);
+		bytes_to_copy = min_t(ssize_t, bytes_to_copy,
+				      lvec[*lvec_current].iov_len
+				      - *lvec_offset);
+
+		target_kaddr = kmap(process_pages[pgs_copied]) + start_offset;
+
+		if (vm_write)
+			ret = copy_from_user(target_kaddr,
+					     lvec[*lvec_current].iov_base
+					     + *lvec_offset,
+					     bytes_to_copy);
+		else
+			ret = copy_to_user(lvec[*lvec_current].iov_base
+					   + *lvec_offset,
+					   target_kaddr, bytes_to_copy);
+		kunmap(process_pages[pgs_copied]);
+		if (ret) {
+			*bytes_copied += bytes_to_copy - ret;
+			pgs_copied++;
+			rc = -EFAULT;
+			goto end;
+		}
+		*bytes_copied += bytes_to_copy;
+		*lvec_offset += bytes_to_copy;
+		if (*lvec_offset == lvec[*lvec_current].iov_len) {
+			/*
+			 * Need to copy remaining part of page into the
+			 * next iovec if there are any bytes left in page
+			 */
+			(*lvec_current)++;
+			*lvec_offset = 0;
+			start_offset = (start_offset + bytes_to_copy)
+				% PAGE_SIZE;
+			if (start_offset)
+				pgs_copied--;
+		} else {
+			start_offset = 0;
+		}
+	}
+
+end:
+	if (vm_write) {
+		for (j = 0; j < pages_pinned; j++) {
+			if (j < pgs_copied)
+				set_page_dirty_lock(process_pages[j]);
+			put_page(process_pages[j]);
+		}
+	} else {
+		for (j = 0; j < pages_pinned; j++)
+			put_page(process_pages[j]);
+	}
+
+	return rc;
+}
+
+/* Maximum number of pages kmalloc'd to hold struct page's during copy */
+#define PVM_MAX_KMALLOC_PAGES (PAGE_SIZE * 2)
+
+/**
+ * process_vm_rw_single_vec - read/write pages from task specified
+ * @addr: start memory address of target process
+ * @len: size of area to copy to/from
+ * @lvec: iovec array specifying where to copy to/from locally
+ * @lvec_cnt: number of elements in iovec array
+ * @lvec_current: index in iovec array we are up to
+ * @lvec_offset: offset in bytes from current iovec iov_base we are up to
+ * @process_pages: struct pages area that can store at least
+ *  nr_pages_to_copy struct page pointers
+ * @mm: mm for task
+ * @task: task to read/write from
+ * @vm_write: 0 means copy from, 1 means copy to
+ * @bytes_copied: returns number of bytes successfully copied
+ * Returns 0 on success or on failure error code
+ */
+static int process_vm_rw_single_vec(unsigned long addr,
+				    unsigned long len,
+				    const struct iovec *lvec,
+				    unsigned long lvec_cnt,
+				    unsigned long *lvec_current,
+				    size_t *lvec_offset,
+				    struct page **process_pages,
+				    struct mm_struct *mm,
+				    struct task_struct *task,
+				    int vm_write,
+				    ssize_t *bytes_copied)
+{
+	unsigned long pa = addr & PAGE_MASK;
+	unsigned long start_offset = addr - pa;
+	unsigned long nr_pages;
+	ssize_t bytes_copied_loop;
+	ssize_t rc = 0;
+	unsigned long nr_pages_copied = 0;
+	unsigned long nr_pages_to_copy;
+	unsigned long max_pages_per_loop = PVM_MAX_KMALLOC_PAGES
+		/ sizeof(struct pages *);
+
+	*bytes_copied = 0;
+
+	/* Work out address and page range required */
+	if (len == 0)
+		return 0;
+	nr_pages = (addr + len - 1) / PAGE_SIZE - addr / PAGE_SIZE + 1;
+
+	while ((nr_pages_copied < nr_pages) && (*lvec_current < lvec_cnt)) {
+		nr_pages_to_copy = min(nr_pages - nr_pages_copied,
+				       max_pages_per_loop);
+
+		rc = process_vm_rw_pages(task, mm, process_pages, pa,
+					 start_offset, len,
+					 lvec, lvec_cnt,
+					 lvec_current, lvec_offset,
+					 vm_write, nr_pages_to_copy,
+					 &bytes_copied_loop);
+		start_offset = 0;
+		*bytes_copied += bytes_copied_loop;
+
+		if (rc < 0) {
+			return rc;
+		} else {
+			len -= bytes_copied_loop;
+			nr_pages_copied += nr_pages_to_copy;
+			pa += nr_pages_to_copy * PAGE_SIZE;
+		}
+	}
+
+	return rc;
+}
+
+/* Maximum number of entries for process pages array
+   which lives on stack */
+#define PVM_MAX_PP_ARRAY_COUNT 16
+
+/**
+ * process_vm_rw_core - core of reading/writing pages from task specified
+ * @pid: PID of process to read/write from/to
+ * @lvec: iovec array specifying where to copy to/from locally
+ * @liovcnt: size of lvec array
+ * @rvec: iovec array specifying where to copy to/from in the other process
+ * @riovcnt: size of rvec array
+ * @flags: currently unused
+ * @vm_write: 0 if reading from other process, 1 if writing to other process
+ * Returns the number of bytes read/written or error code. May
+ *  return less bytes than expected if an error occurs during the copying
+ *  process.
+ */
+static ssize_t process_vm_rw_core(pid_t pid, const struct iovec *lvec,
+				  unsigned long liovcnt,
+				  const struct iovec *rvec,
+				  unsigned long riovcnt,
+				  unsigned long flags, int vm_write)
+{
+	struct task_struct *task;
+	struct page *pp_stack[PVM_MAX_PP_ARRAY_COUNT];
+	struct page **process_pages = pp_stack;
+	struct mm_struct *mm;
+	unsigned long i;
+	ssize_t rc = 0;
+	ssize_t bytes_copied_loop;
+	ssize_t bytes_copied = 0;
+	unsigned long nr_pages = 0;
+	unsigned long nr_pages_iov;
+	unsigned long iov_l_curr_idx = 0;
+	size_t iov_l_curr_offset = 0;
+	ssize_t iov_len;
+
+	/*
+	 * Work out how many pages of struct pages we're going to need
+	 * when eventually calling get_user_pages
+	 */
+	for (i = 0; i < riovcnt; i++) {
+		iov_len = rvec[i].iov_len;
+		if (iov_len > 0) {
+			nr_pages_iov = ((unsigned long)rvec[i].iov_base
+					+ iov_len)
+				/ PAGE_SIZE - (unsigned long)rvec[i].iov_base
+				/ PAGE_SIZE + 1;
+			nr_pages = max(nr_pages, nr_pages_iov);
+		}
+	}
+
+	if (nr_pages == 0)
+		return 0;
+
+	if (nr_pages > PVM_MAX_PP_ARRAY_COUNT) {
+		/* For reliability don't try to kmalloc more than
+		   2 pages worth */
+		process_pages = kmalloc(min_t(size_t, PVM_MAX_KMALLOC_PAGES,
+					      sizeof(struct pages *)*nr_pages),
+					GFP_KERNEL);
+
+		if (!process_pages)
+			return -ENOMEM;
+	}
+
+	/* Get process information */
+	rcu_read_lock();
+	task = find_task_by_vpid(pid);
+	if (task)
+		get_task_struct(task);
+	rcu_read_unlock();
+	if (!task) {
+		rc = -ESRCH;
+		goto free_proc_pages;
+	}
+
+	task_lock(task);
+	if (__ptrace_may_access(task, PTRACE_MODE_ATTACH)) {
+		task_unlock(task);
+		rc = -EPERM;
+		goto put_task_struct;
+	}
+	mm = task->mm;
+
+	if (!mm || (task->flags & PF_KTHREAD)) {
+		task_unlock(task);
+		rc = -EINVAL;
+		goto put_task_struct;
+	}
+
+	atomic_inc(&mm->mm_users);
+	task_unlock(task);
+
+	for (i = 0; i < riovcnt && iov_l_curr_idx < liovcnt; i++) {
+		rc = process_vm_rw_single_vec(
+			(unsigned long)rvec[i].iov_base, rvec[i].iov_len,
+			lvec, liovcnt, &iov_l_curr_idx, &iov_l_curr_offset,
+			process_pages, mm, task, vm_write, &bytes_copied_loop);
+		bytes_copied += bytes_copied_loop;
+		if (rc != 0) {
+			/* If we have managed to copy any data at all then
+			   we return the number of bytes copied. Otherwise
+			   we return the error code */
+			if (bytes_copied)
+				rc = bytes_copied;
+			goto put_mm;
+		}
+	}
+
+	rc = bytes_copied;
+put_mm:
+	mmput(mm);
+
+put_task_struct:
+	put_task_struct(task);
+
+free_proc_pages:
+	if (process_pages != pp_stack)
+		kfree(process_pages);
+	return rc;
+}
+
+/**
+ * process_vm_rw - check iovecs before calling core routine
+ * @pid: PID of process to read/write from/to
+ * @lvec: iovec array specifying where to copy to/from locally
+ * @liovcnt: size of lvec array
+ * @rvec: iovec array specifying where to copy to/from in the other process
+ * @riovcnt: size of rvec array
+ * @flags: currently unused
+ * @vm_write: 0 if reading from other process, 1 if writing to other process
+ * Returns the number of bytes read/written or error code. May
+ *  return less bytes than expected if an error occurs during the copying
+ *  process.
+ */
+static ssize_t process_vm_rw(pid_t pid,
+			     const struct iovec __user *lvec,
+			     unsigned long liovcnt,
+			     const struct iovec __user *rvec,
+			     unsigned long riovcnt,
+			     unsigned long flags, int vm_write)
+{
+	struct iovec iovstack_l[UIO_FASTIOV];
+	struct iovec iovstack_r[UIO_FASTIOV];
+	struct iovec *iov_l = iovstack_l;
+	struct iovec *iov_r = iovstack_r;
+	ssize_t rc;
+
+	if (flags != 0)
+		return -EINVAL;
+
+	/* Check iovecs */
+	if (vm_write)
+		rc = rw_copy_check_uvector(WRITE, lvec, liovcnt, UIO_FASTIOV,
+					   iovstack_l, &iov_l, 1);
+	else
+		rc = rw_copy_check_uvector(READ, lvec, liovcnt, UIO_FASTIOV,
+					   iovstack_l, &iov_l, 1);
+	if (rc <= 0)
+		goto free_iovecs;
+
+	rc = rw_copy_check_uvector(READ, rvec, riovcnt, UIO_FASTIOV,
+				   iovstack_r, &iov_r, 0);
+	if (rc <= 0)
+		goto free_iovecs;
+
+	rc = process_vm_rw_core(pid, iov_l, liovcnt, iov_r, riovcnt, flags,
+				vm_write);
+
+free_iovecs:
+	if (iov_r != iovstack_r)
+		kfree(iov_r);
+	if (iov_l != iovstack_l)
+		kfree(iov_l);
+
+	return rc;
+}
+
+SYSCALL_DEFINE6(process_vm_readv, pid_t, pid, const struct iovec __user *, lvec,
+		unsigned long, liovcnt, const struct iovec __user *, rvec,
+		unsigned long, riovcnt,	unsigned long, flags)
+{
+	return process_vm_rw(pid, lvec, liovcnt, rvec, riovcnt, flags, 0);
+}
+
+SYSCALL_DEFINE6(process_vm_writev, pid_t, pid,
+		const struct iovec __user *, lvec,
+		unsigned long, liovcnt, const struct iovec __user *, rvec,
+		unsigned long, riovcnt,	unsigned long, flags)
+{
+	return process_vm_rw(pid, lvec, liovcnt, rvec, riovcnt, flags, 1);
+}
+
+#ifdef CONFIG_COMPAT
+
+asmlinkage ssize_t
+compat_process_vm_rw(compat_pid_t pid,
+		     const struct compat_iovec __user *lvec,
+		     unsigned long liovcnt,
+		     const struct compat_iovec __user *rvec,
+		     unsigned long riovcnt,
+		     unsigned long flags, int vm_write)
+{
+	struct iovec iovstack_l[UIO_FASTIOV];
+	struct iovec iovstack_r[UIO_FASTIOV];
+	struct iovec *iov_l = iovstack_l;
+	struct iovec *iov_r = iovstack_r;
+	ssize_t rc = -EFAULT;
+
+	if (flags != 0)
+		return -EINVAL;
+
+	if (!access_ok(VERIFY_READ, lvec, liovcnt * sizeof(*lvec)))
+		goto out;
+
+	if (!access_ok(VERIFY_READ, rvec, riovcnt * sizeof(*rvec)))
+		goto out;
+
+	if (vm_write)
+		rc = compat_rw_copy_check_uvector(WRITE, lvec, liovcnt,
+						  UIO_FASTIOV, iovstack_l,
+						  &iov_l, 1);
+	else
+		rc = compat_rw_copy_check_uvector(READ, lvec, liovcnt,
+						  UIO_FASTIOV, iovstack_l,
+						  &iov_l, 1);
+	if (rc <= 0)
+		goto free_iovecs;
+	rc = compat_rw_copy_check_uvector(READ, rvec, riovcnt,
+					  UIO_FASTIOV, iovstack_r,
+					  &iov_r, 0);
+	if (rc <= 0)
+		goto free_iovecs;
+
+	rc = process_vm_rw_core(pid, iov_l, liovcnt, iov_r, riovcnt, flags,
+			   vm_write);
+
+free_iovecs:
+	if (iov_r != iovstack_r)
+		kfree(iov_r);
+	if (iov_l != iovstack_l)
+		kfree(iov_l);
+
+out:
+	return rc;
+}
+
+asmlinkage ssize_t
+compat_sys_process_vm_readv(compat_pid_t pid,
+			    const struct compat_iovec __user *lvec,
+			    unsigned long liovcnt,
+			    const struct compat_iovec __user *rvec,
+			    unsigned long riovcnt,
+			    unsigned long flags)
+{
+	return compat_process_vm_rw(pid, lvec, liovcnt, rvec,
+				    riovcnt, flags, 0);
+}
+
+asmlinkage ssize_t
+compat_sys_process_vm_writev(compat_pid_t pid,
+			     const struct compat_iovec __user *lvec,
+			     unsigned long liovcnt,
+			     const struct compat_iovec __user *rvec,
+			     unsigned long riovcnt,
+			     unsigned long flags)
+{
+	return compat_process_vm_rw(pid, lvec, liovcnt, rvec,
+				    riovcnt, flags, 1);
+}
+
+#endif
diff --git a/security/keys/compat.c b/security/keys/compat.c
index 338b510e90275b1da873ed83aa907c404997d353..4c48e13448f84e0df200ab0a2f0895d0eb5a709c 100644
--- a/security/keys/compat.c
+++ b/security/keys/compat.c
@@ -38,7 +38,7 @@ long compat_keyctl_instantiate_key_iov(
 
 	ret = compat_rw_copy_check_uvector(WRITE, _payload_iov, ioc,
 					   ARRAY_SIZE(iovstack),
-					   iovstack, &iov);
+					   iovstack, &iov, 1);
 	if (ret < 0)
 		return ret;
 	if (ret == 0)
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index eca51918c951d3a28db16bf0f61c749722b6ac64..0b3f5d72af1cecbd06b33c2151ec570a4cfaa2ee 100644
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -1065,7 +1065,7 @@ long keyctl_instantiate_key_iov(key_serial_t id,
 		goto no_payload;
 
 	ret = rw_copy_check_uvector(WRITE, _payload_iov, ioc,
-				    ARRAY_SIZE(iovstack), iovstack, &iov);
+				    ARRAY_SIZE(iovstack), iovstack, &iov, 1);
 	if (ret < 0)
 		return ret;
 	if (ret == 0)