files: Handle the absence of ID in proc fdinfo

This makes crtools correctly abort when working on wrong kernel.
Otherwise all the open files will have the same (garbage) ID and
the subsequent restore will result in broken app.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

cr-dump.c

@@ -307,7 +307,7 @@ out_close:
 static int read_fd_params(pid_t pid, int pid_dir, char *fd, struct fd_parms *p)
 {
 	FILE *file;
-	unsigned int f;
+	int ret;
 
 	file = fopen_proc(pid_dir, "fdinfo/%s", fd);
 	if (!file) {
@@ -316,9 +316,14 @@ static int read_fd_params(pid_t pid, int pid_dir, char *fd, struct fd_parms *p)
 	}
 
 	p->fd_name = atoi(fd);
-	fscanf(file, "pos:\t%li\nflags:\t%o\nid:\t%s\n", &p->pos, &p->flags, p->id);
+	ret = fscanf(file, "pos:\t%li\nflags:\t%o\nid:\t%s\n", &p->pos, &p->flags, p->id);
 	fclose(file);
 
+	if (ret != 3) {
+		pr_err("Bad format of fdinfo file (%d items, want 3)\n", ret);
+		return -1;
+	}
+
 	pr_info("%d fdinfo %s: pos: %16lx flags: %16o id %s\n",
 		pid, fd, p->pos, p->flags, p->id);