ANDROID: dm: Mounting root as linear device when verity disabled (1a6b1e3e) · Commits · e / devices / android_kernel_xiaomi_markw

drivers/md/dm-android-verity.c

+106 −22

Original line number	Original line	Diff line number	Diff line
	@@ -13,6 +13,7 @@
	*/		*/

	#include <linux/buffer_head.h>		#include <linux/buffer_head.h>
			#include <linux/debugfs.h>
	#include <linux/delay.h>		#include <linux/delay.h>
	#include <linux/device.h>		#include <linux/device.h>
	#include <linux/device-mapper.h>		#include <linux/device-mapper.h>
	@@ -43,6 +44,25 @@
	static char verifiedbootstate[VERITY_COMMANDLINE_PARAM_LENGTH];		static char verifiedbootstate[VERITY_COMMANDLINE_PARAM_LENGTH];
	static char veritymode[VERITY_COMMANDLINE_PARAM_LENGTH];		static char veritymode[VERITY_COMMANDLINE_PARAM_LENGTH];

			static bool target_added;
			static bool verity_enabled = true;
			struct dentry *debug_dir;
			static int android_verity_ctr(struct dm_target ti, unsigned argc, char *argv);

			static struct target_type android_verity_target = {
			.name = "android-verity",
			.version = {1, 0, 0},
			.module = THIS_MODULE,
			.ctr = android_verity_ctr,
			.dtr = verity_dtr,
			.map = verity_map,
			.status = verity_status,
			.ioctl = verity_ioctl,
			.merge = verity_merge,
			.iterate_devices = verity_iterate_devices,
			.io_hints = verity_io_hints,
			};

	static int __init verified_boot_state_param(char *line)		static int __init verified_boot_state_param(char *line)
	{		{
	strlcpy(verifiedbootstate, line, sizeof(verifiedbootstate));		strlcpy(verifiedbootstate, line, sizeof(verifiedbootstate));
	@@ -549,6 +569,32 @@ static inline bool test_mult_overflow(sector_t a, u32 b)
	return a > r;		return a > r;
	}		}

			static int add_as_linear_device(struct dm_target ti, char dev)
			{
			/Move to linear mapping defines/
			char *linear_table_args[DM_LINEAR_ARGS] = {dev,
			DM_LINEAR_TARGET_OFFSET};
			int err = 0;

			android_verity_target.dtr = linear_target.dtr,
			android_verity_target.map = linear_target.map,
			android_verity_target.status = linear_target.status,
			android_verity_target.ioctl = linear_target.ioctl,
			android_verity_target.merge = linear_target.merge,
			android_verity_target.iterate_devices = linear_target.iterate_devices,
			android_verity_target.io_hints = NULL;

			err = linear_target.ctr(ti, DM_LINEAR_ARGS, linear_table_args);

			if (!err) {
			DMINFO("Added android-verity as a linear target");
			target_added = true;
			} else
			DMERR("Failed to add android-verity as linear target");

			return err;
			}

	/*		/*
	* Target parameters:		* Target parameters:
	* <key id> Key id of the public key in the system keyring.		* <key id> Key id of the public key in the system keyring.
	@@ -613,13 +659,18 @@ static int android_verity_ctr(struct dm_target ti, unsigned argc, char *argv)

	if (err == VERITY_STATE_DISABLE) {		if (err == VERITY_STATE_DISABLE) {
	DMERR("Mounting root with verity disabled");		DMERR("Mounting root with verity disabled");
	return -EINVAL;		verity_enabled = false;
			/* we would still have to parse the args to figure out
			* the data blocks size. Or may be could map the entire
			* partition similar to mounting the device.
			*/
	} else if (err) {		} else if (err) {
	DMERR("Verity header handle error");		DMERR("Verity header handle error");
	handle_error();		handle_error();
	goto free_metadata;		goto free_metadata;
	}		}

			if (!verity_enabled) {
	err = verify_verity_signature(key_id, metadata);		err = verify_verity_signature(key_id, metadata);

	if (err) {		if (err) {
	@@ -628,6 +679,7 @@ static int android_verity_ctr(struct dm_target ti, unsigned argc, char *argv)
	goto free_metadata;		goto free_metadata;
	} else		} else
	DMINFO("Signature verification success");		DMINFO("Signature verification success");
			}

	table_ptr = metadata->verity_table;		table_ptr = metadata->verity_table;

	@@ -683,6 +735,12 @@ static int android_verity_ctr(struct dm_target ti, unsigned argc, char *argv)
	/* update target length */		/* update target length */
	ti->len = data_sectors;		ti->len = data_sectors;

			/* Setup linear target and free */
			if (!verity_enabled) {
			err = add_as_linear_device(ti, argv[1]);
			goto free_metadata;
			}

	/substitute data_dev and hash_dev/		/substitute data_dev and hash_dev/
	verity_table_args[1] = argv[1];		verity_table_args[1] = argv[1];
	verity_table_args[2] = argv[1];		verity_table_args[2] = argv[1];
	@@ -730,6 +788,13 @@ static int android_verity_ctr(struct dm_target ti, unsigned argc, char *argv)

	err = verity_ctr(ti, no_of_args, verity_table_args);		err = verity_ctr(ti, no_of_args, verity_table_args);

			if (err)
			DMERR("android-verity failed to mount as verity target");
			else {
			target_added = true;
			DMINFO("android-verity mounted as verity target");
			}

	free_metadata:		free_metadata:
	kfree(metadata->header);		kfree(metadata->header);
	kfree(metadata->verity_table);		kfree(metadata->verity_table);
	@@ -737,33 +802,52 @@ free_metadata:
	return err;		return err;
	}		}

	static struct target_type android_verity_target = {
	.name = "android-verity",
	.version = {1, 0, 0},
	.module = THIS_MODULE,
	.ctr = android_verity_ctr,
	.dtr = verity_dtr,
	.map = verity_map,
	.status = verity_status,
	.ioctl = verity_ioctl,
	.merge = verity_merge,
	.iterate_devices = verity_iterate_devices,
	.io_hints = verity_io_hints,
	};

	static int __init dm_android_verity_init(void)		static int __init dm_android_verity_init(void)
	{		{
	int r;		int r;
			struct dentry *file;

	r = dm_register_target(&android_verity_target);		r = dm_register_target(&android_verity_target);
	if (r < 0)		if (r < 0)
	DMERR("register failed %d", r);		DMERR("register failed %d", r);

			/* Tracks the status of the last added target */
			debug_dir = debugfs_create_dir("android_verity", NULL);

			if (IS_ERR_OR_NULL(debug_dir)) {
			DMERR("Cannot create android_verity debugfs directory: %ld",
			PTR_ERR(debug_dir));
			goto end;
			}

			file = debugfs_create_bool("target_added", S_IRUGO, debug_dir,
			(u32 *)&target_added);

			if (IS_ERR_OR_NULL(file)) {
			DMERR("Cannot create android_verity debugfs directory: %ld",
			PTR_ERR(debug_dir));
			debugfs_remove_recursive(debug_dir);
			goto end;
			}

			file = debugfs_create_bool("verity_enabled", S_IRUGO, debug_dir,
			(u32 *)&verity_enabled);

			if (IS_ERR_OR_NULL(file)) {
			DMERR("Cannot create android_verity debugfs directory: %ld",
			PTR_ERR(debug_dir));
			debugfs_remove_recursive(debug_dir);
			}

			end:
	return r;		return r;
	}		}

	static void __exit dm_android_verity_exit(void)		static void __exit dm_android_verity_exit(void)
	{		{
			if (!IS_ERR_OR_NULL(debug_dir))
			debugfs_remove_recursive(debug_dir);

	dm_unregister_target(&android_verity_target);		dm_unregister_target(&android_verity_target);
	}		}

drivers/md/dm-android-verity.h

+5 −0

Original line number	Original line	Diff line number	Diff line
	@@ -44,6 +44,10 @@
	#define VERITY_DEBUG 0		#define VERITY_DEBUG 0

	#define DM_MSG_PREFIX "android-verity"		#define DM_MSG_PREFIX "android-verity"

			#define DM_LINEAR_ARGS 2
			#define DM_LINEAR_TARGET_OFFSET "0"

	/*		/*
	* There can be two formats.		* There can be two formats.
	* if fec is present		* if fec is present
	@@ -89,4 +93,5 @@ struct bio_read {
	int number_of_pages;		int number_of_pages;
	};		};

			extern struct target_type linear_target;
	#endif /* DM_ANDROID_VERITY_H */		#endif /* DM_ANDROID_VERITY_H */

drivers/md/dm-linear.c

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -153,7 +153,7 @@ static int linear_iterate_devices(struct dm_target *ti,
	return fn(ti, lc->dev, lc->start, ti->len, data);		return fn(ti, lc->dev, lc->start, ti->len, data);
	}		}

	static struct target_type linear_target = {		struct target_type linear_target = {
	.name = "linear",		.name = "linear",
	.version = {1, 2, 1},		.version = {1, 2, 1},
	.module = THIS_MODULE,		.module = THIS_MODULE,