swsusp: Fix userland interface

Fix oops caused by 'cat /dev/snapshot', reported by Arkadiusz Miskiewicz, and make it impossible to thaw tasks with the help of the swsusp userland interface while there is a snapshot image ready to save.

Rafael J. Wysocki committed 19 years ago

Commit 2f41ddd1 parent b1d93de1 file · +3 −1Browse files

Showing the changes to kernel (1 of 1 file). Show all

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kernel/power/user.c+3−1

@@ -99,6 +99,8 @@ static ssize_t snapshot_read(struct file filp, char __user buf, · 98 unmodified lines
99	99	ssize_t res;
100	100
101	101	data = filp->private_data;
	102	+ if (!data->ready)
	103	+ return -ENODATA;
102	104	res = snapshot_read_next(&data->handle, count);
103	105	if (res > 0) {
104	106	if (copy_to_user(buf, data_of(data->handle), res))
@@ -245,7 +247,7 @@ static int snapshot_ioctl(struct inode inode, struct file filp, · 140 unmodified lines
245	247	break;
246	248
247	249	case SNAPSHOT_UNFREEZE:
248		− if (!data->frozen)
	250	+ if (!data->frozen \|\| data->ready)
249	251	break;
250	252	mutex_lock(&pm_mutex);
251	253	thaw_processes();