Inter-revision diff: patch 2

Comparing v7 (message) to v15 (message)

--- v7
+++ v15
@@ -1,469 +1,304 @@
-The functions ima_get_kexec_buffer() and ima_free_kexec_buffer(),
-that handle carrying forward the IMA measurement logs on kexec for
-powerpc do not have architecture specific code, but they are currently
-defined for powerpc only.
-
-Move ima_get_kexec_buffer() and ima_free_kexec_buffer() to IMA
-subsystem. A later patch in this series will use these functions for
-carrying forward the IMA measurement log for ARM64.
-
-With the above refactoring arch/powerpc/kexec/ima.c contains only
-functions used when CONFIG_IMA_KEXEC is enabled. Update Makefile
-in arch/powerpc/kexec to include arch/powerpc/kexec/ima.c only
-when CONFIG_IMA_KEXEC is enabled.
-
-Move ima_dump_measurement_list() and ima_add_kexec_buffer() to
-a new file namely ima_kexec_fdt.c in IMA. Update
-security/integrity/ima/Makefile to include ima_kexec_fdt.c only
-when CONFIG_IMA_KEXEC is enabled.
-
-Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
-Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
-Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
+From: Rob Herring <robh@kernel.org>
+
+Both arm64 and powerpc do essentially the same FDT /chosen setup for
+kexec.  The differences are either omissions that arm64 should have
+or additional properties that will be ignored.  The setup code can be
+combined and shared by both powerpc and arm64.
+
+The differences relative to the arm64 version:
+ - If /chosen doesn't exist, it will be created (should never happen).
+ - Any old dtb and initrd reserved memory will be released.
+ - The new initrd and elfcorehdr are marked reserved.
+ - "linux,booted-from-kexec" is set.
+
+The differences relative to the powerpc version:
+ - "kaslr-seed" and "rng-seed" may be set.
+ - "linux,elfcorehdr" is set.
+ - Any existing "linux,usable-memory-range" is removed.
+
+Combine the code for setting up the /chosen node in the FDT and updating
+the memory reservation for kexec, for powerpc and arm64, in
+of_kexec_setup_new_fdt() and move it to "drivers/of/kexec.c".
+
+Signed-off-by: Rob Herring <robh@kernel.org>
+Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
+Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
 ---
- arch/powerpc/include/asm/ima.h         |   3 -
- arch/powerpc/kexec/Makefile            |   7 +-
- arch/powerpc/kexec/ima.c               |  56 ---------
- security/integrity/ima/Makefile        |   1 +
- security/integrity/ima/ima_kexec.c     | 154 +++++++------------------
- security/integrity/ima/ima_kexec_fdt.c | 136 ++++++++++++++++++++++
- 6 files changed, 182 insertions(+), 175 deletions(-)
- create mode 100644 security/integrity/ima/ima_kexec_fdt.c
-
-diff --git a/arch/powerpc/include/asm/ima.h b/arch/powerpc/include/asm/ima.h
-index 6355a85a3289..8975f5e0cab8 100644
---- a/arch/powerpc/include/asm/ima.h
-+++ b/arch/powerpc/include/asm/ima.h
-@@ -6,9 +6,6 @@
+ drivers/of/Makefile |   1 +
+ drivers/of/kexec.c  | 236 ++++++++++++++++++++++++++++++++++++++++++++
+ include/linux/of.h  |   5 +
+ 3 files changed, 242 insertions(+)
+ create mode 100644 drivers/of/kexec.c
+
+diff --git a/drivers/of/Makefile b/drivers/of/Makefile
+index 6e1e5212f058..8ce11955afde 100644
+--- a/drivers/of/Makefile
++++ b/drivers/of/Makefile
+@@ -13,5 +13,6 @@ obj-$(CONFIG_OF_RESERVED_MEM) += of_reserved_mem.o
+ obj-$(CONFIG_OF_RESOLVE)  += resolver.o
+ obj-$(CONFIG_OF_OVERLAY) += overlay.o
+ obj-$(CONFIG_OF_NUMA) += of_numa.o
++obj-$(CONFIG_KEXEC_FILE) += kexec.o
  
- struct kimage;
+ obj-$(CONFIG_OF_UNITTEST) += unittest-data/
+diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
+new file mode 100644
+index 000000000000..4afd3cc1c04a
+--- /dev/null
++++ b/drivers/of/kexec.c
+@@ -0,0 +1,236 @@
++// SPDX-License-Identifier: GPL-2.0-only
++/*
++ * Copyright (C) 2020 Arm Limited
++ *
++ * Based on arch/arm64/kernel/machine_kexec_file.c:
++ *  Copyright (C) 2018 Linaro Limited
++ *
++ * And arch/powerpc/kexec/file_load.c:
++ *  Copyright (C) 2016  IBM Corporation
++ */
++
++#include <linux/kernel.h>
++#include <linux/kexec.h>
++#include <linux/libfdt.h>
++#include <linux/of.h>
++#include <linux/of_fdt.h>
++#include <linux/random.h>
++#include <linux/types.h>
++
++/* relevant device tree properties */
++#define FDT_PROP_KEXEC_ELFHDR	"linux,elfcorehdr"
++#define FDT_PROP_MEM_RANGE	"linux,usable-memory-range"
++#define FDT_PROP_INITRD_START	"linux,initrd-start"
++#define FDT_PROP_INITRD_END	"linux,initrd-end"
++#define FDT_PROP_BOOTARGS	"bootargs"
++#define FDT_PROP_KASLR_SEED	"kaslr-seed"
++#define FDT_PROP_RNG_SEED	"rng-seed"
++#define RNG_SEED_SIZE		128
++
++/**
++ * fdt_find_and_del_mem_rsv - delete memory reservation with given address and size
++ *
++ * @fdt:	Flattened device tree for the current kernel.
++ * @start:	Starting address of the reserved memory.
++ * @size:	Size of the reserved memory.
++ *
++ * Return: 0 on success, or negative errno on error.
++ */
++static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned long size)
++{
++	int i, ret, num_rsvs = fdt_num_mem_rsv(fdt);
++
++	for (i = 0; i < num_rsvs; i++) {
++		u64 rsv_start, rsv_size;
++
++		ret = fdt_get_mem_rsv(fdt, i, &rsv_start, &rsv_size);
++		if (ret) {
++			pr_err("Malformed device tree.\n");
++			return -EINVAL;
++		}
++
++		if (rsv_start == start && rsv_size == size) {
++			ret = fdt_del_mem_rsv(fdt, i);
++			if (ret) {
++				pr_err("Error deleting device tree reservation.\n");
++				return -EINVAL;
++			}
++
++			return 0;
++		}
++	}
++
++	return -ENOENT;
++}
++
++/*
++ * of_kexec_setup_new_fdt - modify /chosen and memory reservation for the next kernel
++ *
++ * @image:		kexec image being loaded.
++ * @fdt:		Flattened device tree for the next kernel.
++ * @initrd_load_addr:	Address where the next initrd will be loaded.
++ * @initrd_len:		Size of the next initrd, or 0 if there will be none.
++ * @cmdline:		Command line for the next kernel, or NULL if there will
++ *			be none.
++ *
++ * Return: 0 on success, or negative errno on error.
++ */
++int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
++			   unsigned long initrd_load_addr, unsigned long initrd_len,
++			   const char *cmdline)
++{
++	int ret, chosen_node;
++	const void *prop;
++
++	/* Remove memory reservation for the current device tree. */
++	ret = fdt_find_and_del_mem_rsv(fdt, __pa(initial_boot_params),
++				       fdt_totalsize(initial_boot_params));
++	if (ret == -EINVAL)
++		return ret;
++
++	chosen_node = fdt_path_offset(fdt, "/chosen");
++	if (chosen_node == -FDT_ERR_NOTFOUND)
++		chosen_node = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"),
++					      "chosen");
++	if (chosen_node < 0) {
++		ret = chosen_node;
++		goto out;
++	}
++
++	ret = fdt_delprop(fdt, chosen_node, FDT_PROP_KEXEC_ELFHDR);
++	if (ret && ret != -FDT_ERR_NOTFOUND)
++		goto out;
++	ret = fdt_delprop(fdt, chosen_node, FDT_PROP_MEM_RANGE);
++	if (ret && ret != -FDT_ERR_NOTFOUND)
++		goto out;
++
++	/* Did we boot using an initrd? */
++	prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL);
++	if (prop) {
++		u64 tmp_start, tmp_end, tmp_size;
++
++		tmp_start = fdt64_to_cpu(*((const fdt64_t *) prop));
++
++		prop = fdt_getprop(fdt, chosen_node, "linux,initrd-end", NULL);
++		if (!prop)
++			return -EINVAL;
++
++		tmp_end = fdt64_to_cpu(*((const fdt64_t *) prop));
++
++		/*
++		 * kexec reserves exact initrd size, while firmware may
++		 * reserve a multiple of PAGE_SIZE, so check for both.
++		 */
++		tmp_size = tmp_end - tmp_start;
++		ret = fdt_find_and_del_mem_rsv(fdt, tmp_start, tmp_size);
++		if (ret == -ENOENT)
++			ret = fdt_find_and_del_mem_rsv(fdt, tmp_start,
++						       round_up(tmp_size, PAGE_SIZE));
++		if (ret == -EINVAL)
++			return ret;
++	}
++
++	/* add initrd-* */
++	if (initrd_load_addr) {
++		ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_INITRD_START,
++				      initrd_load_addr);
++		if (ret)
++			goto out;
++
++		ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_INITRD_END,
++				      initrd_load_addr + initrd_len);
++		if (ret)
++			goto out;
++
++		ret = fdt_add_mem_rsv(fdt, initrd_load_addr, initrd_len);
++		if (ret)
++			goto out;
++
++	} else {
++		ret = fdt_delprop(fdt, chosen_node, FDT_PROP_INITRD_START);
++		if (ret && (ret != -FDT_ERR_NOTFOUND))
++			goto out;
++
++		ret = fdt_delprop(fdt, chosen_node, FDT_PROP_INITRD_END);
++		if (ret && (ret != -FDT_ERR_NOTFOUND))
++			goto out;
++	}
++
++	if (image->type == KEXEC_TYPE_CRASH) {
++		/* add linux,elfcorehdr */
++		ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
++				FDT_PROP_KEXEC_ELFHDR,
++				image->arch.elf_headers_mem,
++				image->arch.elf_headers_sz);
++		if (ret)
++			goto out;
++
++		/*
++		 * Avoid elfcorehdr from being stomped on in kdump kernel by
++		 * setting up memory reserve map.
++		 */
++		ret = fdt_add_mem_rsv(fdt, image->arch.elf_headers_mem,
++				      image->arch.elf_headers_sz);
++		if (ret)
++			goto out;
++
++		/* add linux,usable-memory-range */
++		ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
++				FDT_PROP_MEM_RANGE,
++				crashk_res.start,
++				crashk_res.end - crashk_res.start + 1);
++		if (ret)
++			goto out;
++	}
++
++	/* add bootargs */
++	if (cmdline) {
++		ret = fdt_setprop_string(fdt, chosen_node, FDT_PROP_BOOTARGS, cmdline);
++		if (ret)
++			goto out;
++	} else {
++		ret = fdt_delprop(fdt, chosen_node, FDT_PROP_BOOTARGS);
++		if (ret && (ret != -FDT_ERR_NOTFOUND))
++			goto out;
++	}
++
++	/* add kaslr-seed */
++	ret = fdt_delprop(fdt, chosen_node, FDT_PROP_KASLR_SEED);
++	if (ret == -FDT_ERR_NOTFOUND)
++		ret = 0;
++	else if (ret)
++		goto out;
++
++	if (rng_is_initialized()) {
++		u64 seed = get_random_u64();
++
++		ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_KASLR_SEED, seed);
++		if (ret)
++			goto out;
++	} else {
++		pr_notice("RNG is not initialised: omitting \"%s\" property\n",
++				FDT_PROP_KASLR_SEED);
++	}
++
++	/* add rng-seed */
++	if (rng_is_initialized()) {
++		void *rng_seed;
++
++		ret = fdt_setprop_placeholder(fdt, chosen_node, FDT_PROP_RNG_SEED,
++				RNG_SEED_SIZE, &rng_seed);
++		if (ret)
++			goto out;
++		get_random_bytes(rng_seed, RNG_SEED_SIZE);
++	} else {
++		pr_notice("RNG is not initialised: omitting \"%s\" property\n",
++				FDT_PROP_RNG_SEED);
++	}
++
++	ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
++
++out:
++	if (ret)
++		return (ret == -FDT_ERR_NOSPACE) ? -ENOMEM : -EINVAL;
++
++	return 0;
++}
+diff --git a/include/linux/of.h b/include/linux/of.h
+index 5d51891cbf1a..3375f5295875 100644
+--- a/include/linux/of.h
++++ b/include/linux/of.h
+@@ -558,6 +558,11 @@ int of_map_id(struct device_node *np, u32 id,
+ 	       const char *map_name, const char *map_mask_name,
+ 	       struct device_node **target, u32 *id_out);
  
--int ima_get_kexec_buffer(void **addr, size_t *size);
--int ima_free_kexec_buffer(void);
--
- #ifdef CONFIG_IMA_KEXEC
- int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
- 			      size_t size);
-diff --git a/arch/powerpc/kexec/Makefile b/arch/powerpc/kexec/Makefile
-index 4aff6846c772..f54a9dbff4c8 100644
---- a/arch/powerpc/kexec/Makefile
-+++ b/arch/powerpc/kexec/Makefile
-@@ -9,12 +9,7 @@ obj-$(CONFIG_PPC32)		+= relocate_32.o
++struct kimage;
++int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
++			   unsigned long initrd_load_addr, unsigned long initrd_len,
++			   const char *cmdline);
++
+ #else /* CONFIG_OF */
  
- obj-$(CONFIG_KEXEC_FILE)	+= file_load.o ranges.o file_load_$(BITS).o elf_$(BITS).o
- 
--ifdef CONFIG_HAVE_IMA_KEXEC
--ifdef CONFIG_IMA
--obj-y				+= ima.o
--endif
--endif
--
-+obj-$(CONFIG_IMA_KEXEC)		+= ima.o
- 
- # Disable GCOV, KCOV & sanitizers in odd or sensitive code
- GCOV_PROFILE_core_$(BITS).o := n
-diff --git a/arch/powerpc/kexec/ima.c b/arch/powerpc/kexec/ima.c
-index 2b790230ea15..4fadd8d16891 100644
---- a/arch/powerpc/kexec/ima.c
-+++ b/arch/powerpc/kexec/ima.c
-@@ -30,61 +30,6 @@ static int get_addr_size_cells(int *addr_cells, int *size_cells)
- 	return 0;
- }
- 
--/**
-- * ima_get_kexec_buffer - get IMA buffer from the previous kernel
-- * @addr:	On successful return, set to point to the buffer contents.
-- * @size:	On successful return, set to the buffer size.
-- *
-- * Return: 0 on success, negative errno on error.
-- */
--int ima_get_kexec_buffer(void **addr, size_t *size)
--{
--	int ret, len;
--	unsigned long tmp_addr;
--	size_t tmp_size;
--	const void *prop;
--
--	prop = of_get_property(of_chosen, "linux,ima-kexec-buffer", &len);
--	if (!prop)
--		return -ENOENT;
--
--	ret = do_get_kexec_buffer(prop, len, &tmp_addr, &tmp_size);
--	if (ret)
--		return ret;
--
--	*addr = __va(tmp_addr);
--	*size = tmp_size;
--
--	return 0;
--}
--
--/**
-- * ima_free_kexec_buffer - free memory used by the IMA buffer
-- */
--int ima_free_kexec_buffer(void)
--{
--	int ret;
--	unsigned long addr;
--	size_t size;
--	struct property *prop;
--
--	prop = of_find_property(of_chosen, "linux,ima-kexec-buffer", NULL);
--	if (!prop)
--		return -ENOENT;
--
--	ret = do_get_kexec_buffer(prop->value, prop->length, &addr, &size);
--	if (ret)
--		return ret;
--
--	ret = of_remove_property(of_chosen, prop);
--	if (ret)
--		return ret;
--
--	return memblock_free(addr, size);
--
--}
--
--#ifdef CONFIG_IMA_KEXEC
- /**
-  * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
-  *
-@@ -177,4 +122,3 @@ int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
- 
- 	return 0;
- }
--#endif /* CONFIG_IMA_KEXEC */
-diff --git a/security/integrity/ima/Makefile b/security/integrity/ima/Makefile
-index 67dabca670e2..0c440870a4e9 100644
---- a/security/integrity/ima/Makefile
-+++ b/security/integrity/ima/Makefile
-@@ -14,3 +14,4 @@ ima-$(CONFIG_HAVE_IMA_KEXEC) += ima_kexec.o
- ima-$(CONFIG_IMA_BLACKLIST_KEYRING) += ima_mok.o
- ima-$(CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS) += ima_asymmetric_keys.o
- ima-$(CONFIG_IMA_QUEUE_EARLY_BOOT_KEYS) += ima_queue_keys.o
-+ima-$(CONFIG_IMA_KEXEC) += ima_kexec_fdt.o
-diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c
-index 121de3e04af2..987e464be889 100644
---- a/security/integrity/ima/ima_kexec.c
-+++ b/security/integrity/ima/ima_kexec.c
-@@ -7,131 +7,65 @@
-  * Mimi Zohar <zohar@linux.vnet.ibm.com>
-  */
- 
--#include <linux/seq_file.h>
- #include <linux/vmalloc.h>
- #include <linux/kexec.h>
-+#include <linux/of.h>
-+#include <linux/memblock.h>
-+#include <linux/libfdt.h>
-+#include <linux/ima.h>
- #include "ima.h"
- 
--#ifdef CONFIG_IMA_KEXEC
--static int ima_dump_measurement_list(unsigned long *buffer_size, void **buffer,
--				     unsigned long segment_size)
-+/**
-+ * ima_get_kexec_buffer - get IMA buffer from the previous kernel
-+ * @addr:	On successful return, set to point to the buffer contents.
-+ * @size:	On successful return, set to the buffer size.
-+ *
-+ * Return: 0 on success, negative errno on error.
-+ */
-+static int ima_get_kexec_buffer(void **addr, size_t *size)
- {
--	struct ima_queue_entry *qe;
--	struct seq_file file;
--	struct ima_kexec_hdr khdr;
--	int ret = 0;
--
--	/* segment size can't change between kexec load and execute */
--	file.buf = vmalloc(segment_size);
--	if (!file.buf) {
--		ret = -ENOMEM;
--		goto out;
--	}
--
--	file.size = segment_size;
--	file.read_pos = 0;
--	file.count = sizeof(khdr);	/* reserved space */
--
--	memset(&khdr, 0, sizeof(khdr));
--	khdr.version = 1;
--	list_for_each_entry_rcu(qe, &ima_measurements, later) {
--		if (file.count < file.size) {
--			khdr.count++;
--			ima_measurements_show(&file, qe);
--		} else {
--			ret = -EINVAL;
--			break;
--		}
--	}
--
--	if (ret < 0)
--		goto out;
--
--	/*
--	 * fill in reserved space with some buffer details
--	 * (eg. version, buffer size, number of measurements)
--	 */
--	khdr.buffer_size = file.count;
--	if (ima_canonical_fmt) {
--		khdr.version = cpu_to_le16(khdr.version);
--		khdr.count = cpu_to_le64(khdr.count);
--		khdr.buffer_size = cpu_to_le64(khdr.buffer_size);
--	}
--	memcpy(file.buf, &khdr, sizeof(khdr));
--
--	print_hex_dump(KERN_DEBUG, "ima dump: ", DUMP_PREFIX_NONE,
--			16, 1, file.buf,
--			file.count < 100 ? file.count : 100, true);
--
--	*buffer_size = file.count;
--	*buffer = file.buf;
--out:
--	if (ret == -EINVAL)
--		vfree(file.buf);
--	return ret;
-+	int ret, len;
-+	unsigned long tmp_addr;
-+	size_t tmp_size;
-+	const void *prop;
-+
-+	prop = of_get_property(of_chosen, FDT_PROP_IMA_KEXEC_BUFFER, &len);
-+	if (!prop)
-+		return -ENOENT;
-+
-+	ret = do_get_kexec_buffer(prop, len, &tmp_addr, &tmp_size);
-+	if (ret)
-+		return ret;
-+
-+	*addr = __va(tmp_addr);
-+	*size = tmp_size;
-+	return 0;
- }
- 
--/*
-- * Called during kexec_file_load so that IMA can add a segment to the kexec
-- * image for the measurement list for the next kernel.
-- *
-- * This function assumes that kexec_mutex is held.
-+/**
-+ * ima_free_kexec_buffer - free memory used by the IMA buffer
-  */
--void ima_add_kexec_buffer(struct kimage *image)
-+static int ima_free_kexec_buffer(void)
- {
--	struct kexec_buf kbuf = { .image = image, .buf_align = PAGE_SIZE,
--				  .buf_min = 0, .buf_max = ULONG_MAX,
--				  .top_down = true };
--	unsigned long binary_runtime_size;
--
--	/* use more understandable variable names than defined in kbuf */
--	void *kexec_buffer = NULL;
--	size_t kexec_buffer_size;
--	size_t kexec_segment_size;
- 	int ret;
-+	unsigned long addr;
-+	size_t size;
-+	struct property *prop;
- 
--	/*
--	 * Reserve an extra half page of memory for additional measurements
--	 * added during the kexec load.
--	 */
--	binary_runtime_size = ima_get_binary_runtime_size();
--	if (binary_runtime_size >= ULONG_MAX - PAGE_SIZE)
--		kexec_segment_size = ULONG_MAX;
--	else
--		kexec_segment_size = ALIGN(ima_get_binary_runtime_size() +
--					   PAGE_SIZE / 2, PAGE_SIZE);
--	if ((kexec_segment_size == ULONG_MAX) ||
--	    ((kexec_segment_size >> PAGE_SHIFT) > totalram_pages() / 2)) {
--		pr_err("Binary measurement list too large.\n");
--		return;
--	}
-+	prop = of_find_property(of_chosen, FDT_PROP_IMA_KEXEC_BUFFER, NULL);
-+	if (!prop)
-+		return -ENOENT;
- 
--	ima_dump_measurement_list(&kexec_buffer_size, &kexec_buffer,
--				  kexec_segment_size);
--	if (!kexec_buffer) {
--		pr_err("Not enough memory for the kexec measurement buffer.\n");
--		return;
--	}
-+	ret = do_get_kexec_buffer(prop->value, prop->length, &addr, &size);
-+	if (ret)
-+		return ret;
- 
--	kbuf.buffer = kexec_buffer;
--	kbuf.bufsz = kexec_buffer_size;
--	kbuf.memsz = kexec_segment_size;
--	ret = kexec_add_buffer(&kbuf);
--	if (ret) {
--		pr_err("Error passing over kexec measurement buffer.\n");
--		return;
--	}
--
--	ret = arch_ima_add_kexec_buffer(image, kbuf.mem, kexec_segment_size);
--	if (ret) {
--		pr_err("Error passing over kexec measurement buffer.\n");
--		return;
--	}
-+	ret = of_remove_property(of_chosen, prop);
-+	if (ret)
-+		return ret;
- 
--	pr_debug("kexec measurement buffer for the loaded kernel at 0x%lx.\n",
--		 kbuf.mem);
-+	return memblock_free(addr, size);
- }
--#endif /* IMA_KEXEC */
- 
- /*
-  * Restore the measurement list from the previous kernel.
-diff --git a/security/integrity/ima/ima_kexec_fdt.c b/security/integrity/ima/ima_kexec_fdt.c
-new file mode 100644
-index 000000000000..186051467e5b
---- /dev/null
-+++ b/security/integrity/ima/ima_kexec_fdt.c
-@@ -0,0 +1,136 @@
-+// SPDX-License-Identifier: GPL-2.0-or-later
-+/*
-+ * Copyright (C) 2016 IBM Corporation
-+ *
-+ * Authors:
-+ * Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
-+ * Mimi Zohar <zohar@linux.vnet.ibm.com>
-+ */
-+
-+#include <linux/seq_file.h>
-+#include <linux/vmalloc.h>
-+#include <linux/kexec.h>
-+#include <linux/of.h>
-+#include <linux/memblock.h>
-+#include <linux/libfdt.h>
-+#include <linux/ima.h>
-+#include "ima.h"
-+
-+static int ima_dump_measurement_list(unsigned long *buffer_size, void **buffer,
-+				     unsigned long segment_size)
-+{
-+	struct ima_queue_entry *qe;
-+	struct seq_file file;
-+	struct ima_kexec_hdr khdr;
-+	int ret = 0;
-+
-+	/* segment size can't change between kexec load and execute */
-+	file.buf = vmalloc(segment_size);
-+	if (!file.buf) {
-+		ret = -ENOMEM;
-+		goto out;
-+	}
-+
-+	file.size = segment_size;
-+	file.read_pos = 0;
-+	file.count = sizeof(khdr);	/* reserved space */
-+
-+	memset(&khdr, 0, sizeof(khdr));
-+	khdr.version = 1;
-+	list_for_each_entry_rcu(qe, &ima_measurements, later) {
-+		if (file.count < file.size) {
-+			khdr.count++;
-+			ima_measurements_show(&file, qe);
-+		} else {
-+			ret = -EINVAL;
-+			break;
-+		}
-+	}
-+
-+	if (ret < 0)
-+		goto out;
-+
-+	/*
-+	 * fill in reserved space with some buffer details
-+	 * (eg. version, buffer size, number of measurements)
-+	 */
-+	khdr.buffer_size = file.count;
-+	if (ima_canonical_fmt) {
-+		khdr.version = cpu_to_le16(khdr.version);
-+		khdr.count = cpu_to_le64(khdr.count);
-+		khdr.buffer_size = cpu_to_le64(khdr.buffer_size);
-+	}
-+	memcpy(file.buf, &khdr, sizeof(khdr));
-+
-+	print_hex_dump(KERN_DEBUG, "ima dump: ", DUMP_PREFIX_NONE,
-+			16, 1, file.buf,
-+			file.count < 100 ? file.count : 100, true);
-+
-+	*buffer_size = file.count;
-+	*buffer = file.buf;
-+out:
-+	if (ret == -EINVAL)
-+		vfree(file.buf);
-+	return ret;
-+}
-+
-+/*
-+ * Called during kexec_file_load so that IMA can add a segment to the kexec
-+ * image for the measurement list for the next kernel.
-+ *
-+ * This function assumes that kexec_mutex is held.
-+ */
-+void ima_add_kexec_buffer(struct kimage *image)
-+{
-+	struct kexec_buf kbuf = { .image = image, .buf_align = PAGE_SIZE,
-+				  .buf_min = 0, .buf_max = ULONG_MAX,
-+				  .top_down = true };
-+	unsigned long binary_runtime_size;
-+
-+	/* use more understandable variable names than defined in kbuf */
-+	void *kexec_buffer = NULL;
-+	size_t kexec_buffer_size;
-+	size_t kexec_segment_size;
-+	int ret;
-+
-+	/*
-+	 * Reserve an extra half page of memory for additional measurements
-+	 * added during the kexec load.
-+	 */
-+	binary_runtime_size = ima_get_binary_runtime_size();
-+	if (binary_runtime_size >= ULONG_MAX - PAGE_SIZE)
-+		kexec_segment_size = ULONG_MAX;
-+	else
-+		kexec_segment_size = ALIGN(ima_get_binary_runtime_size() +
-+					   PAGE_SIZE / 2, PAGE_SIZE);
-+	if ((kexec_segment_size == ULONG_MAX) ||
-+	    ((kexec_segment_size >> PAGE_SHIFT) > totalram_pages() / 2)) {
-+		pr_err("Binary measurement list too large.\n");
-+		return;
-+	}
-+
-+	ima_dump_measurement_list(&kexec_buffer_size, &kexec_buffer,
-+				  kexec_segment_size);
-+	if (!kexec_buffer) {
-+		pr_err("Not enough memory for the kexec measurement buffer.\n");
-+		return;
-+	}
-+
-+	kbuf.buffer = kexec_buffer;
-+	kbuf.bufsz = kexec_buffer_size;
-+	kbuf.memsz = kexec_segment_size;
-+	ret = kexec_add_buffer(&kbuf);
-+	if (ret) {
-+		pr_err("Error passing over kexec measurement buffer.\n");
-+		return;
-+	}
-+
-+	ret = arch_ima_add_kexec_buffer(image, kbuf.mem, kexec_segment_size);
-+	if (ret) {
-+		pr_err("Error passing over kexec measurement buffer.\n");
-+		return;
-+	}
-+
-+	pr_debug("kexec measurement buffer for the loaded kernel at 0x%lx.\n",
-+		 kbuf.mem);
-+}
+ static inline void of_core_init(void)
 -- 
-2.28.0
-
+2.30.0
+
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