From 5657cb0797c4ab303f5782442095319bd971257b Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 28 Jun 2017 08:09:45 -0600 Subject: [PATCH] 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 Fixes: c75b1d9421f8 ("fs: add fcntl() interface for setting/getting write life time hints") Signed-off-by: Jens Axboe --- fs/fcntl.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/fs/fcntl.c b/fs/fcntl.c index 67bdc6e8ccad..ed051f825bad 100644 --- a/fs/fcntl.c +++ b/fs/fcntl.c @@ -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; -- 2.20.1