1 files changed, 75 insertions, 14 deletions

diff --git a/fs/compat.c b/fs/compat.c
index baabf203b847..1c859dae758f 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -1196,16 +1196,12 @@ out:
 	return ret;
 }
 
-asmlinkage ssize_t
-compat_sys_readv(unsigned long fd, const struct compat_iovec __user *vec, unsigned long vlen)
+static size_t compat_readv(struct file *file,
+			   const struct compat_iovec __user *vec,
+			   unsigned long vlen, loff_t *pos)
 {
-	struct file *file;
 	ssize_t ret = -EBADF;
 
-	file = fget(fd);
-	if (!file)
-		return -EBADF;
-
 	if (!(file->f_mode & FMODE_READ))
 		goto out;
 
@@ -1213,25 +1209,56 @@ compat_sys_readv(unsigned long fd, const struct compat_iovec __user *vec, unsign
 	if (!file->f_op || (!file->f_op->aio_read && !file->f_op->read))
 		goto out;
 
-	ret = compat_do_readv_writev(READ, file, vec, vlen, &file->f_pos);
+	ret = compat_do_readv_writev(READ, file, vec, vlen, pos);
 
 out:
 	if (ret > 0)
 		add_rchar(current, ret);
 	inc_syscr(current);
-	fput(file);
 	return ret;
 }
 
 asmlinkage ssize_t
-compat_sys_writev(unsigned long fd, const struct compat_iovec __user *vec, unsigned long vlen)
+compat_sys_readv(unsigned long fd, const struct compat_iovec __user *vec,
+		 unsigned long vlen)
 {
 	struct file *file;
-	ssize_t ret = -EBADF;
+	int fput_needed;
+	ssize_t ret;
 
-	file = fget(fd);
+	file = fget_light(fd, &fput_needed);
 	if (!file)
 		return -EBADF;
+	ret = compat_readv(file, vec, vlen, &file->f_pos);
+	fput_light(file, fput_needed);
+	return ret;
+}
+
+asmlinkage ssize_t
+compat_sys_preadv(unsigned long fd, const struct compat_iovec __user *vec,
+		  unsigned long vlen, u32 pos_high, u32 pos_low)
+{
+	loff_t pos = ((loff_t)pos_high << 32) | pos_low;
+	struct file *file;
+	int fput_needed;
+	ssize_t ret;
+
+	if (pos < 0)
+		return -EINVAL;
+	file = fget_light(fd, &fput_needed);
+	if (!file)
+		return -EBADF;
+	ret = compat_readv(file, vec, vlen, &pos);
+	fput_light(file, fput_needed);
+	return ret;
+}
+
+static size_t compat_writev(struct file *file,
+			    const struct compat_iovec __user *vec,
+			    unsigned long vlen, loff_t *pos)
+{
+	ssize_t ret = -EBADF;
+
 	if (!(file->f_mode & FMODE_WRITE))
 		goto out;
 
@@ -1239,13 +1266,47 @@ compat_sys_writev(unsigned long fd, const struct compat_iovec __user *vec, unsig
 	if (!file->f_op || (!file->f_op->aio_write && !file->f_op->write))
 		goto out;
 
-	ret = compat_do_readv_writev(WRITE, file, vec, vlen, &file->f_pos);
+	ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos);
 
 out:
 	if (ret > 0)
 		add_wchar(current, ret);
 	inc_syscw(current);
-	fput(file);
+	return ret;
+}
+
+asmlinkage ssize_t
+compat_sys_writev(unsigned long fd, const struct compat_iovec __user *vec,
+		  unsigned long vlen)
+{
+	struct file *file;
+	int fput_needed;
+	ssize_t ret;
+
+	file = fget_light(fd, &fput_needed);
+	if (!file)
+		return -EBADF;
+	ret = compat_writev(file, vec, vlen, &file->f_pos);
+	fput_light(file, fput_needed);
+	return ret;
+}
+
+asmlinkage ssize_t
+compat_sys_pwritev(unsigned long fd, const struct compat_iovec __user *vec,
+		   unsigned long vlen, u32 pos_high, u32 pos_low)
+{
+	loff_t pos = ((loff_t)pos_high << 32) | pos_low;
+	struct file *file;
+	int fput_needed;
+	ssize_t ret;
+
+	if (pos < 0)
+		return -EINVAL;
+	file = fget_light(fd, &fput_needed);
+	if (!file)
+		return -EBADF;
+	ret = compat_writev(file, vec, vlen, &pos);
+	fput_light(file, fput_needed);
 	return ret;
 }