Merge branch 'linus' into locking/kcsan, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>

init/Kconfig

@@ -767,8 +767,7 @@ config ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
 	bool
 
 config CC_HAS_INT128
-	def_bool y
-	depends on !$(cc-option,-D__SIZEOF_INT128__=0)
+	def_bool !$(cc-option,$(m64-flag) -D__SIZEOF_INT128__=0) && 64BIT
 
 #
 # For architectures that know their GCC __int128 support is sound
@@ -1226,13 +1225,12 @@ endif
 
 config BOOT_CONFIG
 	bool "Boot config support"
-	depends on BLK_DEV_INITRD
-	default y
+	select BLK_DEV_INITRD
 	help
 	  Extra boot config allows system admin to pass a config file as
 	  complemental extension of kernel cmdline when booting.
 	  The boot config file must be attached at the end of initramfs
-	  with checksum and size.
+	  with checksum, size and magic word.
 	  See <file:Documentation/admin-guide/bootconfig.rst> for details.
 
 	  If unsure, say Y.

init/main.c

@@ -269,7 +269,6 @@ static int __init xbc_snprint_cmdline(char *buf, size_t size,
 {
 	struct xbc_node *knode, *vnode;
 	char *end = buf + size;
-	char c = '\"';
 	const char *val;
 	int ret;
 
@@ -280,25 +279,20 @@ static int __init xbc_snprint_cmdline(char *buf, size_t size,
 			return ret;
 
 		vnode = xbc_node_get_child(knode);
-		ret = snprintf(buf, rest(buf, end), "%s%c", xbc_namebuf,
-				vnode ? '=' : ' ');
-		if (ret < 0)
-			return ret;
-		buf += ret;
-		if (!vnode)
+		if (!vnode) {
+			ret = snprintf(buf, rest(buf, end), "%s ", xbc_namebuf);
+			if (ret < 0)
+				return ret;
+			buf += ret;
 			continue;
-
-		c = '\"';
+		}
 		xbc_array_for_each_value(vnode, val) {
-			ret = snprintf(buf, rest(buf, end), "%c%s", c, val);
+			ret = snprintf(buf, rest(buf, end), "%s=\"%s\" ",
+				       xbc_namebuf, val);
 			if (ret < 0)
 				return ret;
 			buf += ret;
-			c = ',';
 		}
-		if (rest(buf, end) > 2)
-			strcpy(buf, "\" ");
-		buf += 2;
 	}
 
 	return buf - (end - size);
@@ -336,7 +330,7 @@ static char * __init xbc_make_cmdline(const char *key)
 	return new_cmdline;
 }
 
-u32 boot_config_checksum(unsigned char *p, u32 size)
+static u32 boot_config_checksum(unsigned char *p, u32 size)
 {
 	u32 ret = 0;
 
@@ -375,7 +369,11 @@ static void __init setup_boot_config(const char *cmdline)
 	if (!initrd_end)
 		goto not_found;
 
-	hdr = (u32 *)(initrd_end - 8);
+	data = (char *)initrd_end - BOOTCONFIG_MAGIC_LEN;
+	if (memcmp(data, BOOTCONFIG_MAGIC, BOOTCONFIG_MAGIC_LEN))
+		goto not_found;
+
+	hdr = (u32 *)(data - 8);
 	size = hdr[0];
 	csum = hdr[1];
 
@@ -419,6 +417,14 @@ not_found:
 }
 #else
 #define setup_boot_config(cmdline)	do { } while (0)
+
+static int __init warn_bootconfig(char *str)
+{
+	pr_warn("WARNING: 'bootconfig' found on the kernel command line but CONFIG_BOOTCONFIG is not set.\n");
+	return 0;
+}
+early_param("bootconfig", warn_bootconfig);
+
 #endif
 
 /* Change NUL term back to "=", to make "param" the whole string. */