Dump memory character devices as a file.

It's work for /dev/zero, /dev/null and other simple devices.
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>

cr-dump.c

@@ -20,6 +20,8 @@
 
 #include <sys/sendfile.h>
 
+#include <linux/major.h>
+
 #include "types.h"
 #include "list.h"
 
@@ -248,7 +250,8 @@ static int dump_one_fd(char *pid_fd_dir, int dir, char *fd_name, unsigned long p
 		goto err;
 	}
 
-	if (S_ISREG(st_buf.st_mode))
+	if (S_ISREG(st_buf.st_mode) ||
+	    (S_ISCHR(st_buf.st_mode) && major(st_buf.st_rdev) == MEM_MAJOR))
 		return dump_one_reg_file(FDINFO_FD, atol(fd_name),
 					 fd, 1, pos, flags, cr_fdset);