Merge branch 'android' into HEAD

Author: JeevakaPrabu

arch/x86/include/asm/cpufeature.h

@@ -154,9 +154,6 @@ extern void clear_cpu_cap(struct cpuinfo_x86 *c, unsigned int bit);
  * Workaround for the sake of BPF compilation which utilizes kernel
  * headers, but clang does not support ASM GOTO and fails the build.
  */
-#ifndef __BPF_TRACING__
-#warning "Compiler lacks ASM_GOTO support. Add -D __BPF_TRACING__ to your compiler arguments"
-#endif
 
 #define static_cpu_has(bit)            boot_cpu_has(bit)
 

drivers/md/Kconfig

@@ -517,6 +517,15 @@ config DM_VERITY_VERIFY_ROOTHASH_SIG
 
 	  If unsure, say N.
 
+config DM_VERITY_AVB
+	tristate "Support AVB specific verity error behavior"
+	depends on DM_VERITY
+	---help---
+	  Enables Android Verified Boot platform-specific error
+	  behavior. In particular, it will modify the vbmeta partition
+	  specified on the kernel command-line when non-transient error
+	  occurs (followed by a panic).
+
 config DM_VERITY_FEC
 	bool "Verity forward error correction support"
 	depends on DM_VERITY

drivers/md/Makefile

@@ -80,6 +80,10 @@ ifeq ($(CONFIG_DM_UEVENT),y)
 dm-mod-objs			+= dm-uevent.o
 endif
 
+ifeq ($(CONFIG_DM_VERITY_AVB),y)
+dm-verity-objs			+= dm-verity-avb.o
+endif
+
 ifeq ($(CONFIG_DM_VERITY_FEC),y)
 dm-verity-objs			+= dm-verity-fec.o
 endif

drivers/md/dm-verity-avb.c

@@ -0,0 +1,229 @@
+/*
+ * Copyright (C) 2017 Google.
+ *
+ * This file is released under the GPLv2.
+ *
+ * Based on drivers/md/dm-verity-chromeos.c
+ */
+
+#include <linux/device-mapper.h>
+#include <linux/module.h>
+#include <linux/mount.h>
+
+#define DM_MSG_PREFIX "verity-avb"
+
+/* Set via module parameters. */
+static char avb_vbmeta_device[64];
+static char avb_invalidate_on_error[4];
+
+static void invalidate_vbmeta_endio(struct bio *bio)
+{
+	if (bio->bi_status)
+		DMERR("invalidate_vbmeta_endio: error %d", bio->bi_status);
+	complete(bio->bi_private);
+}
+
+static int invalidate_vbmeta_submit(struct bio *bio,
+				    struct block_device *bdev,
+				    int op, int access_last_sector,
+				    struct page *page)
+{
+	DECLARE_COMPLETION_ONSTACK(wait);
+
+	bio->bi_private = &wait;
+	bio->bi_end_io = invalidate_vbmeta_endio;
+	bio_set_dev(bio, bdev);
+	bio_set_op_attrs(bio, op, REQ_SYNC);
+
+	bio->bi_iter.bi_sector = 0;
+	if (access_last_sector) {
+		sector_t last_sector;
+
+		last_sector = (i_size_read(bdev->bd_inode)>>SECTOR_SHIFT) - 1;
+		bio->bi_iter.bi_sector = last_sector;
+	}
+	if (!bio_add_page(bio, page, PAGE_SIZE, 0)) {
+		DMERR("invalidate_vbmeta_submit: bio_add_page error");
+		return -EIO;
+	}
+
+	submit_bio(bio);
+	/* Wait up to 2 seconds for completion or fail. */
+	if (!wait_for_completion_timeout(&wait, msecs_to_jiffies(2000)))
+		return -EIO;
+	return 0;
+}
+
+static int invalidate_vbmeta(dev_t vbmeta_devt)
+{
+	int ret = 0;
+	struct block_device *bdev;
+	struct bio *bio;
+	struct page *page;
+	fmode_t dev_mode;
+	/* Ensure we do synchronous unblocked I/O. We may also need
+	 * sync_bdev() on completion, but it really shouldn't.
+	 */
+	int access_last_sector = 0;
+
+	DMINFO("invalidate_vbmeta: acting on device %d:%d",
+	       MAJOR(vbmeta_devt), MINOR(vbmeta_devt));
+
+	/* First we open the device for reading. */
+	dev_mode = FMODE_READ | FMODE_EXCL;
+	bdev = blkdev_get_by_dev(vbmeta_devt, dev_mode,
+				 invalidate_vbmeta);
+	if (IS_ERR(bdev)) {
+		DMERR("invalidate_kernel: could not open device for reading");
+		dev_mode = 0;
+		ret = -ENOENT;
+		goto failed_to_read;
+	}
+
+	bio = bio_alloc(GFP_NOIO, 1);
+	if (!bio) {
+		ret = -ENOMEM;
+		goto failed_bio_alloc;
+	}
+
+	page = alloc_page(GFP_NOIO);
+	if (!page) {
+		ret = -ENOMEM;
+		goto failed_to_alloc_page;
+	}
+
+	access_last_sector = 0;
+	ret = invalidate_vbmeta_submit(bio, bdev, REQ_OP_READ,
+				       access_last_sector, page);
+	if (ret) {
+		DMERR("invalidate_vbmeta: error reading");
+		goto failed_to_submit_read;
+	}
+
+	/* We have a page. Let's make sure it looks right. */
+	if (memcmp("AVB0", page_address(page), 4) == 0) {
+		/* Stamp it. */
+		memcpy(page_address(page), "AVE0", 4);
+		DMINFO("invalidate_vbmeta: found vbmeta partition");
+	} else {
+		/* Could be this is on a AVB footer, check. Also, since the
+		 * AVB footer is in the last 64 bytes, adjust for the fact that
+		 * we're dealing with 512-byte sectors.
+		 */
+		size_t offset = (1<<SECTOR_SHIFT) - 64;
+
+		access_last_sector = 1;
+		ret = invalidate_vbmeta_submit(bio, bdev, REQ_OP_READ,
+					       access_last_sector, page);
+		if (ret) {
+			DMERR("invalidate_vbmeta: error reading");
+			goto failed_to_submit_read;
+		}
+		if (memcmp("AVBf", page_address(page) + offset, 4) != 0) {
+			DMERR("invalidate_vbmeta on non-vbmeta partition");
+			ret = -EINVAL;
+			goto invalid_header;
+		}
+		/* Stamp it. */
+		memcpy(page_address(page) + offset, "AVE0", 4);
+		DMINFO("invalidate_vbmeta: found vbmeta footer partition");
+	}
+
+	/* Now rewrite the changed page - the block dev was being
+	 * changed on read. Let's reopen here.
+	 */
+	blkdev_put(bdev, dev_mode);
+	dev_mode = FMODE_WRITE | FMODE_EXCL;
+	bdev = blkdev_get_by_dev(vbmeta_devt, dev_mode,
+				 invalidate_vbmeta);
+	if (IS_ERR(bdev)) {
+		DMERR("invalidate_vbmeta: could not open device for writing");
+		dev_mode = 0;
+		ret = -ENOENT;
+		goto failed_to_write;
+	}
+
+	/* We re-use the same bio to do the write after the read. Need to reset
+	 * it to initialize bio->bi_remaining.
+	 */
+	bio_reset(bio);
+
+	ret = invalidate_vbmeta_submit(bio, bdev, REQ_OP_WRITE,
+				       access_last_sector, page);
+	if (ret) {
+		DMERR("invalidate_vbmeta: error writing");
+		goto failed_to_submit_write;
+	}
+
+	DMERR("invalidate_vbmeta: completed.");
+	ret = 0;
+failed_to_submit_write:
+failed_to_write:
+invalid_header:
+	__free_page(page);
+failed_to_submit_read:
+	/* Technically, we'll leak a page with the pending bio, but
+	 * we're about to reboot anyway.
+	 */
+failed_to_alloc_page:
+	bio_put(bio);
+failed_bio_alloc:
+	if (dev_mode)
+		blkdev_put(bdev, dev_mode);
+failed_to_read:
+	return ret;
+}
+
+void dm_verity_avb_error_handler(void)
+{
+	dev_t dev;
+
+	DMINFO("AVB error handler called for %s", avb_vbmeta_device);
+
+	if (strcmp(avb_invalidate_on_error, "yes") != 0) {
+		DMINFO("Not configured to invalidate");
+		return;
+	}
+
+	if (avb_vbmeta_device[0] == '\0') {
+		DMERR("avb_vbmeta_device parameter not set");
+		goto fail_no_dev;
+	}
+
+	dev = name_to_dev_t(avb_vbmeta_device);
+	if (!dev) {
+		DMERR("No matching partition for device: %s",
+		      avb_vbmeta_device);
+		goto fail_no_dev;
+	}
+
+	invalidate_vbmeta(dev);
+
+fail_no_dev:
+	;
+}
+
+static int __init dm_verity_avb_init(void)
+{
+	DMINFO("AVB error handler initialized with vbmeta device: %s",
+	       avb_vbmeta_device);
+	return 0;
+}
+
+static void __exit dm_verity_avb_exit(void)
+{
+}
+
+module_init(dm_verity_avb_init);
+module_exit(dm_verity_avb_exit);
+
+MODULE_AUTHOR("David Zeuthen <zeuthen@google.com>");
+MODULE_DESCRIPTION("AVB-specific error handler for dm-verity");
+MODULE_LICENSE("GPL");
+
+/* Declare parameter with no module prefix */
+#undef MODULE_PARAM_PREFIX
+#define MODULE_PARAM_PREFIX	"androidboot.vbmeta."
+module_param_string(device, avb_vbmeta_device, sizeof(avb_vbmeta_device), 0);
+module_param_string(invalidate_on_error, avb_invalidate_on_error,
+		    sizeof(avb_invalidate_on_error), 0);

drivers/md/dm-verity-target.c

@@ -251,8 +251,12 @@ static int verity_handle_err(struct dm_verity *v, enum verity_block_type type,
 	if (v->mode == DM_VERITY_MODE_LOGGING)
 		return 0;
 
-	if (v->mode == DM_VERITY_MODE_RESTART)
+	if (v->mode == DM_VERITY_MODE_RESTART) {
+#ifdef CONFIG_DM_VERITY_AVB
+		dm_verity_avb_error_handler();
+#endif
 		kernel_restart("dm-verity device corrupted");
+	}
 
 	return 1;
 }

drivers/md/dm-verity.h

@@ -128,4 +128,6 @@ extern int verity_hash(struct dm_verity *v, struct ahash_request *req,
 extern int verity_hash_for_block(struct dm_verity *v, struct dm_verity_io *io,
 				 sector_t block, u8 *digest, bool *is_zero);
 
+extern void dm_verity_avb_error_handler(void);
+
 #endif /* DM_VERITY_H */

drivers/misc/Kconfig

@@ -466,6 +466,21 @@ config PVPANIC
 	  a paravirtualized device provided by QEMU; it lets a virtual machine
 	  (guest) communicate panic events to the host.
 
+config UID_SYS_STATS
+	bool "Per-UID statistics"
+	depends on PROFILING && TASK_XACCT && TASK_IO_ACCOUNTING
+	help
+	  Per UID based cpu time statistics exported to /proc/uid_cputime
+	  Per UID based io statistics exported to /proc/uid_io
+	  Per UID based procstat control in /proc/uid_procstat
+
+config UID_SYS_STATS_DEBUG
+	bool "Per-TASK statistics"
+	depends on UID_SYS_STATS
+	default n
+	help
+	  Per TASK based io statistics exported to /proc/uid_io
+
 source "drivers/misc/c2port/Kconfig"
 source "drivers/misc/eeprom/Kconfig"
 source "drivers/misc/cb710/Kconfig"

drivers/misc/Makefile

@@ -57,3 +57,4 @@ obj-y				+= cardreader/
 obj-$(CONFIG_PVPANIC)   	+= pvpanic.o
 obj-$(CONFIG_HABANA_AI)		+= habanalabs/
 obj-$(CONFIG_XILINX_SDFEC)	+= xilinx_sdfec.o
+obj-$(CONFIG_UID_SYS_STATS)	+= uid_sys_stats.o