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;
 }