1 files changed, 14 insertions, 84 deletions

diff --git a/mm/process_vm_access.c b/mm/process_vm_access.c
index de41e830cdac..4bcc11958089 100644
--- a/mm/process_vm_access.c
+++ b/mm/process_vm_access.c
@@ -5,6 +5,7 @@
  * Copyright (C) 2010-2011 Christopher Yeoh <cyeoh@au1.ibm.com>, IBM Corp.
  */
 
+#include <linux/compat.h>
 #include <linux/mm.h>
 #include <linux/uio.h>
 #include <linux/sched.h>
@@ -14,10 +15,6 @@
 #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
  * @pages: array of pointers to pages we want to copy
@@ -104,12 +101,12 @@ static int process_vm_rw_single_vec(unsigned long addr,
 		 * access remotely because task/mm might not
 		 * current/current->mm
 		 */
-		down_read(&mm->mmap_sem);
-		pinned_pages = pin_user_pages_remote(task, mm, pa, pinned_pages,
+		mmap_read_lock(mm);
+		pinned_pages = pin_user_pages_remote(mm, pa, pinned_pages,
 						     flags, process_pages,
 						     NULL, &locked);
 		if (locked)
-			up_read(&mm->mmap_sem);
+			mmap_read_unlock(mm);
 		if (pinned_pages <= 0)
 			return -EFAULT;
 
@@ -206,7 +203,7 @@ static ssize_t process_vm_rw_core(pid_t pid, struct iov_iter *iter,
 	if (!mm || IS_ERR(mm)) {
 		rc = IS_ERR(mm) ? PTR_ERR(mm) : -ESRCH;
 		/*
-		 * Explicitly map EACCES to EPERM as EPERM is a more a
+		 * Explicitly map EACCES to EPERM as EPERM is a more
 		 * appropriate error code for process_vw_readv/writev
 		 */
 		if (rc == -EACCES)
@@ -263,7 +260,7 @@ static ssize_t process_vm_rw(pid_t pid,
 	struct iovec iovstack_l[UIO_FASTIOV];
 	struct iovec iovstack_r[UIO_FASTIOV];
 	struct iovec *iov_l = iovstack_l;
-	struct iovec *iov_r = iovstack_r;
+	struct iovec *iov_r;
 	struct iov_iter iter;
 	ssize_t rc;
 	int dir = vm_write ? WRITE : READ;
@@ -276,20 +273,18 @@ static ssize_t process_vm_rw(pid_t pid,
 	if (rc < 0)
 		return rc;
 	if (!iov_iter_count(&iter))
-		goto free_iovecs;
-
-	rc = rw_copy_check_uvector(CHECK_IOVEC_ONLY, rvec, riovcnt, UIO_FASTIOV,
-				   iovstack_r, &iov_r);
-	if (rc <= 0)
-		goto free_iovecs;
-
+		goto free_iov_l;
+	iov_r = iovec_from_user(rvec, riovcnt, UIO_FASTIOV, iovstack_r,
+				in_compat_syscall());
+	if (IS_ERR(iov_r)) {
+		rc = PTR_ERR(iov_r);
+		goto free_iov_l;
+	}
 	rc = process_vm_rw_core(pid, &iter, iov_r, riovcnt, flags, vm_write);
-
-free_iovecs:
 	if (iov_r != iovstack_r)
 		kfree(iov_r);
+free_iov_l:
 	kfree(iov_l);
-
 	return rc;
 }
 
@@ -307,68 +302,3 @@ SYSCALL_DEFINE6(process_vm_writev, pid_t, pid,
 {
 	return process_vm_rw(pid, lvec, liovcnt, rvec, riovcnt, flags, 1);
 }
-
-#ifdef CONFIG_COMPAT
-
-static 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;
-	struct iov_iter iter;
-	ssize_t rc = -EFAULT;
-	int dir = vm_write ? WRITE : READ;
-
-	if (flags != 0)
-		return -EINVAL;
-
-	rc = compat_import_iovec(dir, lvec, liovcnt, UIO_FASTIOV, &iov_l, &iter);
-	if (rc < 0)
-		return rc;
-	if (!iov_iter_count(&iter))
-		goto free_iovecs;
-	rc = compat_rw_copy_check_uvector(CHECK_IOVEC_ONLY, rvec, riovcnt,
-					  UIO_FASTIOV, iovstack_r,
-					  &iov_r);
-	if (rc <= 0)
-		goto free_iovecs;
-
-	rc = process_vm_rw_core(pid, &iter, iov_r, riovcnt, flags, vm_write);
-
-free_iovecs:
-	if (iov_r != iovstack_r)
-		kfree(iov_r);
-	kfree(iov_l);
-	return rc;
-}
-
-COMPAT_SYSCALL_DEFINE6(process_vm_readv, compat_pid_t, pid,
-		       const struct compat_iovec __user *, lvec,
-		       compat_ulong_t, liovcnt,
-		       const struct compat_iovec __user *, rvec,
-		       compat_ulong_t, riovcnt,
-		       compat_ulong_t, flags)
-{
-	return compat_process_vm_rw(pid, lvec, liovcnt, rvec,
-				    riovcnt, flags, 0);
-}
-
-COMPAT_SYSCALL_DEFINE6(process_vm_writev, compat_pid_t, pid,
-		       const struct compat_iovec __user *, lvec,
-		       compat_ulong_t, liovcnt,
-		       const struct compat_iovec __user *, rvec,
-		       compat_ulong_t, riovcnt,
-		       compat_ulong_t, flags)
-{
-	return compat_process_vm_rw(pid, lvec, liovcnt, rvec,
-				    riovcnt, flags, 1);
-}
-
-#endif