PM / sleep: handle the compat case in snapshot_set_swap_area()

Use in_compat_syscall to copy directly from the 32-bit ABI structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Christoph Hellwig 2020-04-06 13:58:35 +02:00 committed by Rafael J. Wysocki
parent 88a77559cc
commit 0f5c4c6e0e

View File

@ -196,28 +196,44 @@ unlock:
return res;
}
struct compat_resume_swap_area {
compat_loff_t offset;
u32 dev;
} __packed;
static int snapshot_set_swap_area(struct snapshot_data *data,
void __user *argp)
{
struct resume_swap_area swap_area;
sector_t offset;
dev_t swdev;
if (swsusp_swap_in_use())
return -EPERM;
if (copy_from_user(&swap_area, argp, sizeof(swap_area)))
return -EFAULT;
if (in_compat_syscall()) {
struct compat_resume_swap_area swap_area;
if (copy_from_user(&swap_area, argp, sizeof(swap_area)))
return -EFAULT;
swdev = new_decode_dev(swap_area.dev);
offset = swap_area.offset;
} else {
struct resume_swap_area swap_area;
if (copy_from_user(&swap_area, argp, sizeof(swap_area)))
return -EFAULT;
swdev = new_decode_dev(swap_area.dev);
offset = swap_area.offset;
}
/*
* User space encodes device types as two-byte values,
* so we need to recode them
*/
swdev = new_decode_dev(swap_area.dev);
if (!swdev) {
data->swap = -1;
return -EINVAL;
}
offset = swap_area.offset;
data->swap = swap_type_of(swdev, offset, NULL);
if (data->swap < 0)
return -ENODEV;
@ -394,12 +410,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
}
#ifdef CONFIG_COMPAT
struct compat_resume_swap_area {
compat_loff_t offset;
u32 dev;
} __packed;
static long
snapshot_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
@ -410,33 +420,13 @@ snapshot_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
case SNAPSHOT_AVAIL_SWAP_SIZE:
case SNAPSHOT_ALLOC_SWAP_PAGE:
case SNAPSHOT_CREATE_IMAGE:
case SNAPSHOT_SET_SWAP_AREA:
return snapshot_ioctl(file, cmd,
(unsigned long) compat_ptr(arg));
case SNAPSHOT_SET_SWAP_AREA: {
struct compat_resume_swap_area __user *u_swap_area =
compat_ptr(arg);
struct resume_swap_area swap_area;
mm_segment_t old_fs;
int err;
err = get_user(swap_area.offset, &u_swap_area->offset);
err |= get_user(swap_area.dev, &u_swap_area->dev);
if (err)
return -EFAULT;
old_fs = get_fs();
set_fs(KERNEL_DS);
err = snapshot_ioctl(file, SNAPSHOT_SET_SWAP_AREA,
(unsigned long) &swap_area);
set_fs(old_fs);
return err;
}
default:
return snapshot_ioctl(file, cmd, arg);
}
}
#endif /* CONFIG_COMPAT */
static const struct file_operations snapshot_fops = {