From 2f41dddbbd7193fb5cdae0a24db4d378d56885fd Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sat, 16 Jun 2007 10:16:03 -0700 Subject: [PATCH] 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. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/power/user.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/power/user.c b/kernel/power/user.c index 24d7d78e6f..d65305b515 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -99,6 +99,8 @@ static ssize_t snapshot_read(struct file *filp, char __user *buf, ssize_t res; data = filp->private_data; + if (!data->ready) + return -ENODATA; res = snapshot_read_next(&data->handle, count); if (res > 0) { if (copy_to_user(buf, data_of(data->handle), res)) @@ -245,7 +247,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, break; case SNAPSHOT_UNFREEZE: - if (!data->frozen) + if (!data->frozen || data->ready) break; mutex_lock(&pm_mutex); thaw_processes(); -- 2.39.5