1 files changed, 56 insertions, 15 deletions

diff --git a/init/initramfs.c b/init/initramfs.c
index d9c941c0c3ca..d3c56fcb30b8 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -5,6 +5,7 @@
 #include <linux/fcntl.h>
 #include <linux/delay.h>
 #include <linux/string.h>
+#include <linux/dirent.h>
 #include <linux/syscalls.h>
 #include <linux/utime.h>
 
@@ -166,8 +167,6 @@ static __initdata char *victim;
 static __initdata unsigned count;
 static __initdata loff_t this_header, next_header;
 
-static __initdata int dry_run;
-
 static inline void __init eat(unsigned n)
 {
 	victim += n;
@@ -229,10 +228,6 @@ static int __init do_header(void)
 	parse_header(collected);
 	next_header = this_header + N_ALIGN(name_len) + body_len;
 	next_header = (next_header + 3) & ~3;
-	if (dry_run) {
-		read_into(name_buf, N_ALIGN(name_len), GotName);
-		return 0;
-	}
 	state = SkipIt;
 	if (name_len <= 0 || name_len > PATH_MAX)
 		return 0;
@@ -303,8 +298,6 @@ static int __init do_name(void)
 		free_hash();
 		return 0;
 	}
-	if (dry_run)
-		return 0;
 	clean_path(collected, mode);
 	if (S_ISREG(mode)) {
 		int ml = maybe_link();
@@ -476,10 +469,9 @@ static void __init flush_window(void)
 	outcnt = 0;
 }
 
-static char * __init unpack_to_rootfs(char *buf, unsigned len, int check_only)
+static char * __init unpack_to_rootfs(char *buf, unsigned len)
 {
 	int written;
-	dry_run = check_only;
 	header_buf = kmalloc(110, GFP_KERNEL);
 	symlink_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, GFP_KERNEL);
 	name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL);
@@ -574,10 +566,57 @@ skip:
 	initrd_end = 0;
 }
 
+#define BUF_SIZE 1024
+static void __init clean_rootfs(void)
+{
+	int fd;
+	void *buf;
+	struct linux_dirent64 *dirp;
+	int count;
+
+	fd = sys_open("/", O_RDONLY, 0);
+	WARN_ON(fd < 0);
+	if (fd < 0)
+		return;
+	buf = kzalloc(BUF_SIZE, GFP_KERNEL);
+	WARN_ON(!buf);
+	if (!buf) {
+		sys_close(fd);
+		return;
+	}
+
+	dirp = buf;
+	count = sys_getdents64(fd, dirp, BUF_SIZE);
+	while (count > 0) {
+		while (count > 0) {
+			struct stat st;
+			int ret;
+
+			ret = sys_newlstat(dirp->d_name, &st);
+			WARN_ON_ONCE(ret);
+			if (!ret) {
+				if (S_ISDIR(st.st_mode))
+					sys_rmdir(dirp->d_name);
+				else
+					sys_unlink(dirp->d_name);
+			}
+
+			count -= dirp->d_reclen;
+			dirp = (void *)dirp + dirp->d_reclen;
+		}
+		dirp = buf;
+		memset(buf, 0, BUF_SIZE);
+		count = sys_getdents64(fd, dirp, BUF_SIZE);
+	}
+
+	sys_close(fd);
+	kfree(buf);
+}
+
 static int __init populate_rootfs(void)
 {
 	char *err = unpack_to_rootfs(__initramfs_start,
-			 __initramfs_end - __initramfs_start, 0);
+			 __initramfs_end - __initramfs_start);
 	if (err)
 		panic(err);
 	if (initrd_start) {
@@ -585,13 +624,15 @@ static int __init populate_rootfs(void)
 		int fd;
 		printk(KERN_INFO "checking if image is initramfs...");
 		err = unpack_to_rootfs((char *)initrd_start,
-			initrd_end - initrd_start, 1);
+			initrd_end - initrd_start);
 		if (!err) {
 			printk(" it is\n");
-			unpack_to_rootfs((char *)initrd_start,
-				initrd_end - initrd_start, 0);
 			free_initrd();
 			return 0;
+		} else {
+			clean_rootfs();
+			unpack_to_rootfs(__initramfs_start,
+				 __initramfs_end - __initramfs_start);
 		}
 		printk("it isn't (%s); looks like an initrd\n", err);
 		fd = sys_open("/initrd.image", O_WRONLY|O_CREAT, 0700);
@@ -604,7 +645,7 @@ static int __init populate_rootfs(void)
 #else
 		printk(KERN_INFO "Unpacking initramfs...");
 		err = unpack_to_rootfs((char *)initrd_start,
-			initrd_end - initrd_start, 0);
+			initrd_end - initrd_start);
 		if (err)
 			panic(err);
 		printk(" done\n");