fs/fcntl: use copy_to/from_user() for u64 types

Some architectures (at least PPC) doesn't like get/put_user with
64-bit types on a 32-bit system. Use the variably sized copy
to/from user variants instead.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: c75b1d9421 ("fs: add fcntl() interface for setting/getting write life time hints")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2017-06-28 08:09:45 -06:00
parent e9d5d4a0c1
commit 5657cb0797
1 changed files with 9 additions and 4 deletions

View File

@ -264,15 +264,18 @@ static long fcntl_rw_hint(struct file *file, unsigned int cmd,
struct inode *inode = file_inode(file);
u64 *argp = (u64 __user *)arg;
enum rw_hint hint;
u64 h;
switch (cmd) {
case F_GET_FILE_RW_HINT:
if (put_user(file_write_hint(file), argp))
h = file_write_hint(file);
if (copy_to_user(argp, &h, sizeof(*argp)))
return -EFAULT;
return 0;
case F_SET_FILE_RW_HINT:
if (get_user(hint, argp))
if (copy_from_user(&h, argp, sizeof(h)))
return -EFAULT;
hint = (enum rw_hint) h;
if (!rw_hint_valid(hint))
return -EINVAL;
@ -281,12 +284,14 @@ static long fcntl_rw_hint(struct file *file, unsigned int cmd,
spin_unlock(&file->f_lock);
return 0;
case F_GET_RW_HINT:
if (put_user(inode->i_write_hint, argp))
h = inode->i_write_hint;
if (copy_to_user(argp, &h, sizeof(*argp)))
return -EFAULT;
return 0;
case F_SET_RW_HINT:
if (get_user(hint, argp))
if (copy_from_user(&h, argp, sizeof(h)))
return -EFAULT;
hint = (enum rw_hint) h;
if (!rw_hint_valid(hint))
return -EINVAL;