1 files changed, 127 insertions, 72 deletions

diff --git a/init/initramfs.c b/init/initramfs.c
index 2f3d96dc3db6..6ddbfb17fb8f 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/init.h>
 #include <linux/async.h>
+#include <linux/export.h>
 #include <linux/fs.h>
 #include <linux/slab.h>
 #include <linux/types.h>
@@ -11,14 +12,23 @@
 #include <linux/syscalls.h>
 #include <linux/utime.h>
 #include <linux/file.h>
+#include <linux/kstrtox.h>
 #include <linux/memblock.h>
 #include <linux/mm.h>
 #include <linux/namei.h>
 #include <linux/init_syscalls.h>
 #include <linux/umh.h>
+#include <linux/security.h>
+#include <linux/overflow.h>
 
-static ssize_t __init xwrite(struct file *file, const char *p, size_t count,
-		loff_t *pos)
+#include "do_mounts.h"
+#include "initramfs_internal.h"
+
+static __initdata bool csum_present;
+static __initdata u32 io_csum;
+
+static ssize_t __init xwrite(struct file *file, const unsigned char *p,
+		size_t count, loff_t *pos)
 {
 	ssize_t out = 0;
 
@@ -33,6 +43,13 @@ static ssize_t __init xwrite(struct file *file, const char *p, size_t count,
 		} else if (rv == 0)
 			break;
 
+		if (csum_present) {
+			ssize_t i;
+
+			for (i = 0; i < rv; i++)
+				io_csum += p[i];
+		}
+
 		p += rv;
 		out += rv;
 		count -= rv;
@@ -48,15 +65,8 @@ static void __init error(char *x)
 		message = x;
 }
 
-static void panic_show_mem(const char *fmt, ...)
-{
-	va_list args;
-
-	show_mem(0, NULL);
-	va_start(args, fmt);
-	panic(fmt, args);
-	va_end(args);
-}
+#define panic_show_mem(fmt, ...) \
+	({ show_mem(); panic(fmt, ##__VA_ARGS__); })
 
 /* link hash */
 
@@ -68,6 +78,7 @@ static __initdata struct hash {
 	struct hash *next;
 	char name[N_ALIGN(PATH_MAX)];
 } *head[32];
+static __initdata bool hardlink_seen;
 
 static inline int hash(int major, int minor, int ino)
 {
@@ -98,49 +109,55 @@ static char __init *find_link(int major, int minor, int ino,
 	q->minor = minor;
 	q->ino = ino;
 	q->mode = mode;
-	strcpy(q->name, name);
+	strscpy(q->name, name);
 	q->next = NULL;
 	*p = q;
+	hardlink_seen = true;
 	return NULL;
 }
 
 static void __init free_hash(void)
 {
 	struct hash **p, *q;
-	for (p = head; p < head + 32; p++) {
+	for (p = head; hardlink_seen && p < head + 32; p++) {
 		while (*p) {
 			q = *p;
 			*p = q->next;
 			kfree(q);
 		}
 	}
+	hardlink_seen = false;
 }
 
-static long __init do_utime(char *filename, time64_t mtime)
+#ifdef CONFIG_INITRAMFS_PRESERVE_MTIME
+static void __init do_utime(char *filename, time64_t mtime)
 {
-	struct timespec64 t[2];
+	struct timespec64 t[2] = { { .tv_sec = mtime }, { .tv_sec = mtime } };
+	init_utimes(filename, t);
+}
 
-	t[0].tv_sec = mtime;
-	t[0].tv_nsec = 0;
-	t[1].tv_sec = mtime;
-	t[1].tv_nsec = 0;
-	return init_utimes(filename, t);
+static void __init do_utime_path(const struct path *path, time64_t mtime)
+{
+	struct timespec64 t[2] = { { .tv_sec = mtime }, { .tv_sec = mtime } };
+	vfs_utimes(path, t);
 }
 
 static __initdata LIST_HEAD(dir_list);
 struct dir_entry {
 	struct list_head list;
-	char *name;
 	time64_t mtime;
+	char name[];
 };
 
-static void __init dir_add(const char *name, time64_t mtime)
+static void __init dir_add(const char *name, size_t nlen, time64_t mtime)
 {
-	struct dir_entry *de = kmalloc(sizeof(struct dir_entry), GFP_KERNEL);
+	struct dir_entry *de;
+
+	de = kmalloc(struct_size(de, name, nlen), GFP_KERNEL);
 	if (!de)
 		panic_show_mem("can't allocate dir_entry buffer");
 	INIT_LIST_HEAD(&de->list);
-	de->name = kstrdup(name, GFP_KERNEL);
+	strscpy(de->name, name, nlen);
 	de->mtime = mtime;
 	list_add(&de->list, &dir_list);
 }
@@ -151,10 +168,15 @@ static void __init dir_utime(void)
 	list_for_each_entry_safe(de, tmp, &dir_list, list) {
 		list_del(&de->list);
 		do_utime(de->name, de->mtime);
-		kfree(de->name);
 		kfree(de);
 	}
 }
+#else
+static void __init do_utime(char *filename, time64_t mtime) {}
+static void __init do_utime_path(const struct path *path, time64_t mtime) {}
+static void __init dir_add(const char *name, size_t nlen, time64_t mtime) {}
+static void __init dir_utime(void) {}
+#endif
 
 static __initdata time64_t mtime;
 
@@ -166,18 +188,16 @@ static __initdata unsigned long body_len, name_len;
 static __initdata uid_t uid;
 static __initdata gid_t gid;
 static __initdata unsigned rdev;
+static __initdata u32 hdr_csum;
 
 static void __init parse_header(char *s)
 {
-	unsigned long parsed[12];
-	char buf[9];
+	unsigned long parsed[13];
 	int i;
 
-	buf[8] = '\0';
-	for (i = 0, s += 6; i < 12; i++, s += 8) {
-		memcpy(buf, s, 8);
-		parsed[i] = simple_strtoul(buf, NULL, 16);
-	}
+	for (i = 0, s += 6; i < 13; i++, s += 8)
+		parsed[i] = simple_strntoul(s, NULL, 16, 8);
+
 	ino = parsed[0];
 	mode = parsed[1];
 	uid = parsed[2];
@@ -189,6 +209,7 @@ static void __init parse_header(char *s)
 	minor = parsed[8];
 	rdev = new_encode_dev(MKDEV(parsed[9], parsed[10]));
 	name_len = parsed[11];
+	hdr_csum = parsed[12];
 }
 
 /* FSM */
@@ -237,7 +258,7 @@ static __initdata char *header_buf, *symlink_buf, *name_buf;
 
 static int __init do_start(void)
 {
-	read_into(header_buf, 110, GotHeader);
+	read_into(header_buf, CPIO_HDRLEN, GotHeader);
 	return 0;
 }
 
@@ -257,12 +278,15 @@ static int __init do_collect(void)
 
 static int __init do_header(void)
 {
-	if (memcmp(collected, "070707", 6)==0) {
-		error("incorrect cpio method used: use -H newc option");
-		return 1;
-	}
-	if (memcmp(collected, "070701", 6)) {
-		error("no cpio magic");
+	if (!memcmp(collected, "070701", 6)) {
+		csum_present = false;
+	} else if (!memcmp(collected, "070702", 6)) {
+		csum_present = true;
+	} else {
+		if (memcmp(collected, "070707", 6) == 0)
+			error("incorrect cpio method used: use -H newc option");
+		else
+			error("no cpio magic");
 		return 1;
 	}
 	parse_header(collected);
@@ -338,6 +362,15 @@ static int __init do_name(void)
 {
 	state = SkipIt;
 	next_state = Reset;
+
+	/* name_len > 0 && name_len <= PATH_MAX checked in do_header */
+	if (collected[name_len - 1] != '\0') {
+		pr_err("initramfs name without nulterm: %.*s\n",
+		       (int)name_len, collected);
+		error("malformed archive");
+		return 1;
+	}
+
 	if (strcmp(collected, "TRAILER!!!") == 0) {
 		free_hash();
 		return 0;
@@ -346,13 +379,14 @@ static int __init do_name(void)
 	if (S_ISREG(mode)) {
 		int ml = maybe_link();
 		if (ml >= 0) {
-			int openflags = O_WRONLY|O_CREAT;
+			int openflags = O_WRONLY|O_CREAT|O_LARGEFILE;
 			if (ml != 1)
 				openflags |= O_TRUNC;
 			wfile = filp_open(collected, openflags, mode);
 			if (IS_ERR(wfile))
 				return 0;
 			wfile_pos = 0;
+			io_csum = 0;
 
 			vfs_fchown(wfile, uid, gid);
 			vfs_fchmod(wfile, mode);
@@ -364,7 +398,7 @@ static int __init do_name(void)
 		init_mkdir(collected, mode);
 		init_chown(collected, uid, gid, 0);
 		init_chmod(collected, mode);
-		dir_add(collected, mtime);
+		dir_add(collected, name_len, mtime);
 	} else if (S_ISBLK(mode) || S_ISCHR(mode) ||
 		   S_ISFIFO(mode) || S_ISSOCK(mode)) {
 		if (maybe_link() == 0) {
@@ -380,15 +414,13 @@ static int __init do_name(void)
 static int __init do_copy(void)
 {
 	if (byte_count >= body_len) {
-		struct timespec64 t[2] = { };
 		if (xwrite(wfile, victim, body_len, &wfile_pos) != body_len)
 			error("write error");
 
-		t[0].tv_sec = mtime;
-		t[1].tv_sec = mtime;
-		vfs_utimes(&wfile->f_path, t);
-
+		do_utime_path(&wfile->f_path, mtime);
 		fput(wfile);
+		if (csum_present && io_csum != hdr_csum)
+			error("bad data checksum");
 		eat(body_len);
 		state = SkipIt;
 		return 0;
@@ -403,6 +435,12 @@ static int __init do_copy(void)
 
 static int __init do_symlink(void)
 {
+	if (collected[name_len - 1] != '\0') {
+		pr_err("initramfs symlink without nulterm: %.*s\n",
+		       (int)name_len, collected);
+		error("malformed archive");
+		return 1;
+	}
 	collected[N_ALIGN(name_len) + body_len] = '\0';
 	clean_path(collected, 0);
 	init_symlink(collected + N_ALIGN(name_len), collected);
@@ -436,7 +474,7 @@ static long __init write_buffer(char *buf, unsigned long len)
 
 static long __init flush_buffer(void *bufv, unsigned long len)
 {
-	char *buf = (char *) bufv;
+	char *buf = bufv;
 	long written;
 	long origLen = len;
 	if (message)
@@ -457,24 +495,37 @@ static long __init flush_buffer(void *bufv, unsigned long len)
 	return origLen;
 }
 
-static unsigned long my_inptr; /* index of next byte to be processed in inbuf */
+static unsigned long my_inptr __initdata; /* index of next byte to be processed in inbuf */
 
 #include <linux/decompress/generic.h>
 
-static char * __init unpack_to_rootfs(char *buf, unsigned long len)
+/**
+ * unpack_to_rootfs - decompress and extract an initramfs archive
+ * @buf: input initramfs archive to extract
+ * @len: length of initramfs data to process
+ *
+ * Returns: NULL for success or an error message string
+ *
+ * This symbol shouldn't be used externally. It's available for unit tests.
+ */
+char * __init unpack_to_rootfs(char *buf, unsigned long len)
 {
 	long written;
 	decompress_fn decompress;
 	const char *compress_name;
-	static __initdata char msg_buf[64];
-
-	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);
+	struct {
+		char header[CPIO_HDRLEN];
+		char symlink[PATH_MAX + N_ALIGN(PATH_MAX) + 1];
+		char name[N_ALIGN(PATH_MAX)];
+	} *bufs = kmalloc(sizeof(*bufs), GFP_KERNEL);
 
-	if (!header_buf || !symlink_buf || !name_buf)
+	if (!bufs)
 		panic_show_mem("can't allocate buffers");
 
+	header_buf = bufs->header;
+	symlink_buf = bufs->symlink;
+	name_buf = bufs->name;
+
 	state = Start;
 	this_header = 0;
 	message = NULL;
@@ -502,12 +553,9 @@ static char * __init unpack_to_rootfs(char *buf, unsigned long len)
 			if (res)
 				error("decompressor failed");
 		} else if (compress_name) {
-			if (!message) {
-				snprintf(msg_buf, sizeof msg_buf,
-					 "compression method %s not configured",
-					 compress_name);
-				message = msg_buf;
-			}
+			pr_err("compression method %s not configured\n",
+			       compress_name);
+			error("decompressor failed");
 		} else
 			error("invalid magic at start of compressed archive");
 		if (state != Reset)
@@ -517,9 +565,9 @@ static char * __init unpack_to_rootfs(char *buf, unsigned long len)
 		len -= my_inptr;
 	}
 	dir_utime();
-	kfree(name_buf);
-	kfree(symlink_buf);
-	kfree(header_buf);
+	/* free any hardlink state collected without optional TRAILER!!! */
+	free_hash();
+	kfree(bufs);
 	return message;
 }
 
@@ -546,8 +594,7 @@ __setup("keepinitrd", keepinitrd_setup);
 static bool __initdata initramfs_async = true;
 static int __init initramfs_async_setup(char *str)
 {
-	strtobool(str, &initramfs_async);
-	return 1;
+	return kstrtobool(str, &initramfs_async) == 0;
 }
 __setup("initramfs_async=", initramfs_async_setup);
 
@@ -556,6 +603,8 @@ extern unsigned long __initramfs_size;
 #include <linux/initrd.h>
 #include <linux/kexec.h>
 
+static BIN_ATTR(initrd, 0440, sysfs_bin_attr_simple_read, NULL, 0);
+
 void __init reserve_initrd_mem(void)
 {
 	phys_addr_t start;
@@ -614,7 +663,7 @@ void __weak __init free_initrd_mem(unsigned long start, unsigned long end)
 			"initrd");
 }
 
-#ifdef CONFIG_KEXEC_CORE
+#ifdef CONFIG_CRASH_RESERVE
 static bool __init kexec_free_initrd(void)
 {
 	unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
@@ -651,11 +700,9 @@ static void __init populate_initrd_image(char *err)
 	struct file *file;
 	loff_t pos = 0;
 
-	unpack_to_rootfs(__initramfs_start, __initramfs_size);
-
 	printk(KERN_INFO "rootfs image is not initramfs (%s); looks like an initrd\n",
 			err);
-	file = filp_open("/initrd.image", O_WRONLY | O_CREAT, 0700);
+	file = filp_open("/initrd.image", O_WRONLY|O_CREAT|O_LARGEFILE, 0700);
 	if (IS_ERR(file))
 		return;
 
@@ -693,16 +740,24 @@ static void __init do_populate_rootfs(void *unused, async_cookie_t cookie)
 	}
 
 done:
+	security_initramfs_populated();
+
 	/*
 	 * If the initrd region is overlapped with crashkernel reserved region,
 	 * free only memory that is not part of crashkernel region.
 	 */
-	if (!do_retain_initrd && initrd_start && !kexec_free_initrd())
+	if (!do_retain_initrd && initrd_start && !kexec_free_initrd()) {
 		free_initrd_mem(initrd_start, initrd_end);
+	} else if (do_retain_initrd && initrd_start) {
+		bin_attr_initrd.size = initrd_end - initrd_start;
+		bin_attr_initrd.private = (void *)initrd_start;
+		if (sysfs_create_bin_file(firmware_kobj, &bin_attr_initrd))
+			pr_err("Failed to create initrd sysfs file");
+	}
 	initrd_start = 0;
 	initrd_end = 0;
 
-	flush_delayed_fput();
+	init_flush_fput();
 }
 
 static ASYNC_DOMAIN_EXCLUSIVE(initramfs_domain);