Carry forward IMA measurement log on kexec on ARM64

fdt_appendprop_addrrange() function adds a property, with the given name, to the device tree at the given node offset, and also sets the address and size of the property. This function should be used to add "linux,ima-kexec-buffer" property to the device tree and set the address and size of the IMA measurement buffer, instead of using custom function.

Use fdt_appendprop_addrrange() to add "linux,ima-kexec-buffer" property to the device tree. This property holds the address and size of the IMA measurement buffer that needs to be passed from the current kernel to the next kernel across kexec system call.

Remove custom code that is used in setup_ima_buffer() to add "linux,ima-kexec-buffer" property to the device tree.

Signed-off-by Lakshmi Ramasubramanian <[email protected]>

---
  arch/powerpc/kexec/ima.c | 51 ++++++----------------------------------
  1 file changed, 7 insertions(+), 44 deletions(-)

arch/powerpc/kexec/ima.c +7 -44

index 720e50e490b6..d579d3da4715 100644
@@ -11,6 +11,7 @@
  #include <linux/of.h>
  #include <linux/memblock.h>
  #include <linux/libfdt.h>
+#include <asm/ima.h>
 
  static int get_addr_size_cells(int *addr_cells, int *size_cells)
  {

@@ -145,27 +146,6 @@ int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
  	return 0;
  }
 
-static int write_number(void *p, u64 value, int cells)
-{
-	if (cells == 1) {
-		u32 tmp;
-
-		if (value > U32_MAX)
-			return -EINVAL;
-
-		tmp = cpu_to_be32(value);
-		memcpy(p, &tmp, sizeof(tmp));
-	} else if (cells == 2) {
-		u64 tmp;
-
-		tmp = cpu_to_be64(value);
-		memcpy(p, &tmp, sizeof(tmp));
-	} else
-		return -EINVAL;
-
-	return 0;
-}
-
  /**
   * setup_ima_buffer - add IMA buffer information to the fdt
   * @image:		kexec image being loaded.

@@ -176,35 +156,18 @@ static int write_number(void *p, u64 value, int cells)
   */
  int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
  {
-	int ret, addr_cells, size_cells, entry_size;
-	u8 value[16];
+	int ret;
 
  	remove_ima_buffer(fdt, chosen_node);
  	if (!image->arch.ima_buffer_size)
  		return 0;
 
-	ret = get_addr_size_cells(&addr_cells, &size_cells);
+	ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+				       "linux,ima-kexec-buffer",
+				       image->arch.ima_buffer_addr,
+				       image->arch.ima_buffer_size);
  	if (ret)
-		return ret;
-
-	entry_size = 4 * (addr_cells + size_cells);
-
-	if (entry_size > sizeof(value))
-		return -EINVAL;
-
-	ret = write_number(value, image->arch.ima_buffer_addr, addr_cells);
-	if (ret)
-		return ret;
-
-	ret = write_number(value + 4 * addr_cells, image->arch.ima_buffer_size,
-			   size_cells);
-	if (ret)
-		return ret;
-
-	ret = fdt_setprop(fdt, chosen_node, "linux,ima-kexec-buffer", value,
-			  entry_size);
-	if (ret < 0)
-		return -EINVAL;
+		return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);
 
  	ret = fdt_add_mem_rsv(fdt, image->arch.ima_buffer_addr,
  			      image->arch.ima_buffer_size);

The functions defined in "arch/powerpc/kexec/ima.c" handle setting up and freeing the resources required to carry over the IMA measurement list from the current kernel to the next kernel across kexec system call. These functions do not have architecture specific code, but are currently limited to powerpc.

Move setup_ima_buffer() call into of_kexec_setup_new_fdt().

Move architecture independent functions from "arch/powerpc/kexec/ima.c" to "drivers/of/kexec.c". Delete "arch/powerpc/kexec/ima.c" and "arch/powerpc/include/asm/ima.h". Remove references to the deleted files in powerpc and in ima.

delete_fdt_mem_rsv() defined in "arch/powerpc/kexec/file_load.c" is not used anymore. Remove this function.

Signed-off-by Lakshmi Ramasubramanian <[email protected]>

---
  arch/powerpc/include/asm/ima.h     |  30 -----
  arch/powerpc/include/asm/kexec.h   |   1 -
  arch/powerpc/kexec/Makefile        |   7 -
  arch/powerpc/kexec/file_load.c     |  39 ------
  arch/powerpc/kexec/ima.c           | 182 --------------------------
  drivers/of/kexec.c                 | 198 +++++++++++++++++++++++++++++
  include/linux/of.h                 |  17 +++
  security/integrity/ima/ima.h       |   4 -
  security/integrity/ima/ima_kexec.c |   2 +
  9 files changed, 217 insertions(+), 263 deletions(-)

delete mode 100644 arch/powerpc/include/asm/ima.h delete mode 100644 arch/powerpc/kexec/ima.c

arch/powerpc/include/asm/ima.h deleted +0 -30

deleted file mode 100644
index ead488cf3981..000000000000
@@ -1,30 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_POWERPC_IMA_H
-#define _ASM_POWERPC_IMA_H
-
-struct kimage;
-
-int ima_get_kexec_buffer(void **addr, size_t *size);
-int ima_free_kexec_buffer(void);
-
-#ifdef CONFIG_IMA
-void remove_ima_buffer(void *fdt, int chosen_node);
-#else
-static inline void remove_ima_buffer(void *fdt, int chosen_node) {}
-#endif
-
-#ifdef CONFIG_IMA_KEXEC
-int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
-			      size_t size);
-
-int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node);
-#else
-static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
-				   int chosen_node)
-{
-	remove_ima_buffer(fdt, chosen_node);
-	return 0;
-}
-#endif /* CONFIG_IMA_KEXEC */
-
-#endif /* _ASM_POWERPC_IMA_H */

arch/powerpc/include/asm/kexec.h +0 -1

index dbf09d2f36d0..d4b7d2d6191d 100644
@@ -126,7 +126,6 @@ int setup_purgatory(struct kimage *image, const void *slave_code,
  int setup_new_fdt(const struct kimage *image, void *fdt,
  		  unsigned long initrd_load_addr, unsigned long initrd_len,
  		  const char *cmdline);
-int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size);
 
  #ifdef CONFIG_PPC64
  struct kexec_buf;

arch/powerpc/kexec/Makefile +0 -7

index 4aff6846c772..b6c52608cb49 100644
@@ -9,13 +9,6 @@ obj-$(CONFIG_PPC32)		+= relocate_32.o
 
  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
-
-
  # Disable GCOV, KCOV & sanitizers in odd or sensitive code
  GCOV_PROFILE_core_$(BITS).o := n
  KCOV_INSTRUMENT_core_$(BITS).o := n

arch/powerpc/kexec/file_load.c +0 -39

index 956bcb2d1ec2..f37652ccb8a1 100644
@@ -20,7 +20,6 @@
  #include <linux/of_fdt.h>
  #include <linux/libfdt.h>
  #include <asm/setup.h>
-#include <asm/ima.h>
 
  #define SLAVE_CODE_SIZE		256	/* First 0x100 bytes */
 

@@ -110,38 +109,6 @@ int setup_purgatory(struct kimage *image, const void *slave_code,
  	return 0;
  }
 
-/**
- * delete_fdt_mem_rsv - delete memory reservation with given address and size
- *
- * Return: 0 on success, or negative errno on error.
- */
-int delete_fdt_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++) {
-		uint64_t 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;
-}
-
  /*
   * setup_new_fdt - modify /chosen and memory reservation for the next kernel
   * @image:		kexec image being loaded.

@@ -163,12 +130,6 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
  	if (ret)
  		goto err;
 
-	ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
-	if (ret) {
-		pr_err("Error setting up the new device tree.\n");
-		return ret;
-	}
-
  	return 0;
 
  err:

arch/powerpc/kexec/ima.c deleted +0 -182

deleted file mode 100644
index d579d3da4715..000000000000
@@ -1,182 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Copyright (C) 2016 IBM Corporation
- *
- * Authors:
- * Thiago Jung Bauermann <[email protected]>
- */
-
-#include <linux/slab.h>
-#include <linux/kexec.h>
-#include <linux/of.h>
-#include <linux/memblock.h>
-#include <linux/libfdt.h>
-#include <asm/ima.h>
-
-static int get_addr_size_cells(int *addr_cells, int *size_cells)
-{
-	struct device_node *root;
-
-	root = of_find_node_by_path("/");
-	if (!root)
-		return -EINVAL;
-
-	*addr_cells = of_n_addr_cells(root);
-	*size_cells = of_n_size_cells(root);
-
-	of_node_put(root);
-
-	return 0;
-}
-
-static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
-			       size_t *size)
-{
-	int ret, addr_cells, size_cells;
-
-	ret = get_addr_size_cells(&addr_cells, &size_cells);
-	if (ret)
-		return ret;
-
-	if (len < 4 * (addr_cells + size_cells))
-		return -ENOENT;
-
-	*addr = of_read_number(prop, addr_cells);
-	*size = of_read_number(prop + 4 * addr_cells, 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);
-
-}
-
-/**
- * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
- *
- * The IMA measurement buffer is of no use to a subsequent kernel, so we always
- * remove it from the device tree.
- */
-void remove_ima_buffer(void *fdt, int chosen_node)
-{
-	int ret, len;
-	unsigned long addr;
-	size_t size;
-	const void *prop;
-
-	prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
-	if (!prop)
-		return;
-
-	ret = do_get_kexec_buffer(prop, len, &addr, &size);
-	fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
-	if (ret)
-		return;
-
-	ret = delete_fdt_mem_rsv(fdt, addr, size);
-	if (!ret)
-		pr_debug("Removed old IMA buffer reservation.\n");
-}
-
-#ifdef CONFIG_IMA_KEXEC
-/**
- * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
- *
- * Architectures should use this function to pass on the IMA buffer
- * information to the next kernel.
- *
- * Return: 0 on success, negative errno on error.
- */
-int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
-			      size_t size)
-{
-	image->arch.ima_buffer_addr = load_addr;
-	image->arch.ima_buffer_size = size;
-
-	return 0;
-}
-
-/**
- * setup_ima_buffer - add IMA buffer information to the fdt
- * @image:		kexec image being loaded.
- * @fdt:		Flattened device tree for the next kernel.
- * @chosen_node:	Offset to the chosen node.
- *
- * Return: 0 on success, or negative errno on error.
- */
-int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
-{
-	int ret;
-
-	remove_ima_buffer(fdt, chosen_node);
-	if (!image->arch.ima_buffer_size)
-		return 0;
-
-	ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
-				       "linux,ima-kexec-buffer",
-				       image->arch.ima_buffer_addr,
-				       image->arch.ima_buffer_size);
-	if (ret)
-		return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);
-
-	ret = fdt_add_mem_rsv(fdt, image->arch.ima_buffer_addr,
-			      image->arch.ima_buffer_size);
-	if (ret)
-		return -EINVAL;
-
-	pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
-		 image->arch.ima_buffer_addr, image->arch.ima_buffer_size);
-
-	return 0;
-}
-#endif /* CONFIG_IMA_KEXEC */

drivers/of/kexec.c +198 -0

index 66787be081fe..a6ab35f16dd2 100644
@@ -10,10 +10,12 @@
   */
 
  #include <linux/kernel.h>
+#include <linux/slab.h>
  #include <linux/kexec.h>
  #include <linux/libfdt.h>
  #include <linux/of.h>
  #include <linux/of_fdt.h>
+#include <linux/memblock.h>
  #include <linux/random.h>
  #include <linux/types.h>
 

@@ -59,6 +61,141 @@ static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned lon
  	return -ENOENT;
  }
 
+/**
+ * get_addr_size_cells - Get address and size of root node
+ *
+ * @addr_cells: Return address of the root node
+ * @size_cells: Return size of the root node
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int get_addr_size_cells(int *addr_cells, int *size_cells)
+{
+	struct device_node *root;
+
+	root = of_find_node_by_path("/");
+	if (!root)
+		return -EINVAL;
+
+	*addr_cells = of_n_addr_cells(root);
+	*size_cells = of_n_size_cells(root);
+
+	of_node_put(root);
+
+	return 0;
+}
+
+/**
+ * do_get_kexec_buffer - Get address and size of device tree property
+ *
+ * @prop: Device tree property
+ * @len: Size of @prop
+ * @addr: Return address of the node
+ * @size: Return size of the node
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
+			       size_t *size)
+{
+	int ret, addr_cells, size_cells;
+
+	ret = get_addr_size_cells(&addr_cells, &size_cells);
+	if (ret)
+		return ret;
+
+	if (len < 4 * (addr_cells + size_cells))
+		return -ENOENT;
+
+	*addr = of_read_number(prop, addr_cells);
+	*size = of_read_number(prop + 4 * addr_cells, 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);
+}
+
+/**
+ * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
+ *
+ * @fdt: Flattened Device Tree to update
+ * @chosen_node: Offset to the chosen node in the device tree
+ *
+ * The IMA measurement buffer is of no use to a subsequent kernel, so we always
+ * remove it from the device tree.
+ */
+void remove_ima_buffer(void *fdt, int chosen_node)
+{
+	int ret, len;
+	unsigned long addr;
+	size_t size;
+	const void *prop;
+
+	prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
+	if (!prop)
+		return;
+
+	ret = do_get_kexec_buffer(prop, len, &addr, &size);
+	fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
+	if (ret)
+		return;
+
+	ret = fdt_find_and_del_mem_rsv(fdt, addr, size);
+	if (!ret)
+		pr_debug("Removed old IMA buffer reservation.\n");
+}
+
  /*
   * of_kexec_setup_new_fdt - modify /chosen and memory reservation for the next kernel
   *

@@ -219,6 +356,10 @@ int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
  	}
 
  	ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+	if (ret)
+		goto out;
+
+	ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
 
  out:
  	if (ret)

@@ -226,3 +367,60 @@ int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
 
  	return 0;
  }
+
+#ifdef CONFIG_IMA_KEXEC
+/**
+ * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
+ *
+ * @image: kimage struct to set IMA buffer data
+ * @load_addr: Starting address where IMA buffer is loaded at
+ * @size: Number of bytes in the IMA buffer
+ *
+ * Architectures should use this function to pass on the IMA buffer
+ * information to the next kernel.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
+			      size_t size)
+{
+	image->arch.ima_buffer_addr = load_addr;
+	image->arch.ima_buffer_size = size;
+
+	return 0;
+}
+
+/**
+ * setup_ima_buffer - add IMA buffer information to the fdt
+ * @image:		kexec image being loaded.
+ * @fdt:		Flattened device tree for the next kernel.
+ * @chosen_node:	Offset to the chosen node.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
+{
+	int ret;
+
+	remove_ima_buffer(fdt, chosen_node);
+	if (!image->arch.ima_buffer_size)
+		return 0;
+
+	ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+				       "linux,ima-kexec-buffer",
+				       image->arch.ima_buffer_addr,
+				       image->arch.ima_buffer_size);
+	if (ret)
+		return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);
+
+	ret = fdt_add_mem_rsv(fdt, image->arch.ima_buffer_addr,
+			      image->arch.ima_buffer_size);
+	if (ret)
+		return -EINVAL;
+
+	pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
+		 image->arch.ima_buffer_addr, image->arch.ima_buffer_size);
+
+	return 0;
+}
+#endif /* CONFIG_IMA_KEXEC */

include/linux/of.h +17 -0

index 3375f5295875..7477f2266d8f 100644
@@ -562,6 +562,23 @@ 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);
+int ima_get_kexec_buffer(void **addr, size_t *size);
+int ima_free_kexec_buffer(void);
+void remove_ima_buffer(void *fdt, int chosen_node);
+
+#ifdef CONFIG_IMA_KEXEC
+int arch_ima_add_kexec_buffer(struct kimage *image,
+			      unsigned long load_addr,
+			      size_t size);
+int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node);
+#else
+static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
+				   int chosen_node)
+{
+	remove_ima_buffer(fdt, chosen_node);
+	return 0;
+}
+#endif /* CONFIG_IMA_KEXEC */
 
  #else /* CONFIG_OF */
 

security/integrity/ima/ima.h +0 -4

index 6ebefec616e4..7c3947ad3773 100644
@@ -24,10 +24,6 @@
 
  #include "../integrity.h"
 
-#ifdef CONFIG_HAVE_IMA_KEXEC
-#include <asm/ima.h>
-#endif
-
  enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
  		     IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
  enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8, TPM_PCR10 = 10 };

security/integrity/ima/ima_kexec.c +2 -0

index 121de3e04af2..3d6a8820e2a5 100644
@@ -9,7 +9,9 @@
 
  #include <linux/seq_file.h>
  #include <linux/vmalloc.h>
+#include <linux/of.h>
  #include <linux/kexec.h>
+#include <linux/ima.h>
  #include "ima.h"
 
  #ifdef CONFIG_IMA_KEXEC

The functions defined in "arch/powerpc/kexec/ima.c" handle setting up and freeing the resources required to carry over the IMA measurement list from the current kernel to the next kernel across kexec system call. These functions do not have architecture specific code, but are currently limited to powerpc.

Move setup_ima_buffer() call into of_kexec_setup_new_fdt().

Move architecture independent functions from "arch/powerpc/kexec/ima.c" to "drivers/of/kexec.c". Delete "arch/powerpc/kexec/ima.c" and "arch/powerpc/include/asm/ima.h". Remove references to the deleted files in powerpc and in ima.

delete_fdt_mem_rsv() defined in "arch/powerpc/kexec/file_load.c" is not used anymore. Remove this function.

Signed-off-by Lakshmi Ramasubramanian <[email protected]>

---
 arch/powerpc/include/asm/ima.h     |  30 -----
 arch/powerpc/include/asm/kexec.h   |   1 -
 arch/powerpc/kexec/Makefile        |   7 -
 arch/powerpc/kexec/file_load.c     |  39 ------
 arch/powerpc/kexec/ima.c           | 182 --------------------------
 drivers/of/kexec.c                 | 198 +++++++++++++++++++++++++++++
 include/linux/of.h                 |  17 +++
 security/integrity/ima/ima.h       |   4 -
 security/integrity/ima/ima_kexec.c |   2 +
 9 files changed, 217 insertions(+), 263 deletions(-)
 delete mode 100644 arch/powerpc/include/asm/ima.h
 delete mode 100644 arch/powerpc/kexec/ima.c

arch/powerpc/include/asm/ima.h deleted +0 -30

deleted file mode 100644
index ead488cf3981..000000000000
@@ -1,30 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_POWERPC_IMA_H
-#define _ASM_POWERPC_IMA_H
-
-struct kimage;
-
-int ima_get_kexec_buffer(void **addr, size_t *size);
-int ima_free_kexec_buffer(void);
-
-#ifdef CONFIG_IMA
-void remove_ima_buffer(void *fdt, int chosen_node);
-#else
-static inline void remove_ima_buffer(void *fdt, int chosen_node) {}
-#endif
-
-#ifdef CONFIG_IMA_KEXEC
-int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
-			      size_t size);
-
-int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node);
-#else
-static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
-				   int chosen_node)
-{
-	remove_ima_buffer(fdt, chosen_node);
-	return 0;
-}
-#endif /* CONFIG_IMA_KEXEC */
-
-#endif /* _ASM_POWERPC_IMA_H */

arch/powerpc/include/asm/kexec.h +0 -1

index dbf09d2f36d0..d4b7d2d6191d 100644
@@ -126,7 +126,6 @@ int setup_purgatory(struct kimage *image, const void *slave_code,
 int setup_new_fdt(const struct kimage *image, void *fdt,
 		  unsigned long initrd_load_addr, unsigned long initrd_len,
 		  const char *cmdline);
-int delete_fdt_mem_rsv(void *fdt, unsigned long start, unsigned long size);
 
 #ifdef CONFIG_PPC64
 struct kexec_buf;

arch/powerpc/kexec/Makefile +0 -7

index 4aff6846c772..b6c52608cb49 100644
@@ -9,13 +9,6 @@ obj-$(CONFIG_PPC32)		+= relocate_32.o
 
 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
-
-
 # Disable GCOV, KCOV & sanitizers in odd or sensitive code
 GCOV_PROFILE_core_$(BITS).o := n
 KCOV_INSTRUMENT_core_$(BITS).o := n

arch/powerpc/kexec/file_load.c +0 -39

index 956bcb2d1ec2..f37652ccb8a1 100644
@@ -20,7 +20,6 @@
 #include <linux/of_fdt.h>
 #include <linux/libfdt.h>
 #include <asm/setup.h>
-#include <asm/ima.h>
 
 #define SLAVE_CODE_SIZE		256	/* First 0x100 bytes */
 

@@ -110,38 +109,6 @@ int setup_purgatory(struct kimage *image, const void *slave_code,
 	return 0;
 }
 
-/**
- * delete_fdt_mem_rsv - delete memory reservation with given address and size
- *
- * Return: 0 on success, or negative errno on error.
- */
-int delete_fdt_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++) {
-		uint64_t 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;
-}
-
 /*
  * setup_new_fdt - modify /chosen and memory reservation for the next kernel
  * @image:		kexec image being loaded.

@@ -163,12 +130,6 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
 	if (ret)
 		goto err;
 
-	ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
-	if (ret) {
-		pr_err("Error setting up the new device tree.\n");
-		return ret;
-	}
-
 	return 0;
 
 err:

arch/powerpc/kexec/ima.c deleted +0 -182

deleted file mode 100644
index d579d3da4715..000000000000
@@ -1,182 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * Copyright (C) 2016 IBM Corporation
- *
- * Authors:
- * Thiago Jung Bauermann <[email protected]>
- */
-
-#include <linux/slab.h>
-#include <linux/kexec.h>
-#include <linux/of.h>
-#include <linux/memblock.h>
-#include <linux/libfdt.h>
-#include <asm/ima.h>
-
-static int get_addr_size_cells(int *addr_cells, int *size_cells)
-{
-	struct device_node *root;
-
-	root = of_find_node_by_path("/");
-	if (!root)
-		return -EINVAL;
-
-	*addr_cells = of_n_addr_cells(root);
-	*size_cells = of_n_size_cells(root);
-
-	of_node_put(root);
-
-	return 0;
-}
-
-static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
-			       size_t *size)
-{
-	int ret, addr_cells, size_cells;
-
-	ret = get_addr_size_cells(&addr_cells, &size_cells);
-	if (ret)
-		return ret;
-
-	if (len < 4 * (addr_cells + size_cells))
-		return -ENOENT;
-
-	*addr = of_read_number(prop, addr_cells);
-	*size = of_read_number(prop + 4 * addr_cells, 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);
-
-}
-
-/**
- * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
- *
- * The IMA measurement buffer is of no use to a subsequent kernel, so we always
- * remove it from the device tree.
- */
-void remove_ima_buffer(void *fdt, int chosen_node)
-{
-	int ret, len;
-	unsigned long addr;
-	size_t size;
-	const void *prop;
-
-	prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
-	if (!prop)
-		return;
-
-	ret = do_get_kexec_buffer(prop, len, &addr, &size);
-	fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
-	if (ret)
-		return;
-
-	ret = delete_fdt_mem_rsv(fdt, addr, size);
-	if (!ret)
-		pr_debug("Removed old IMA buffer reservation.\n");
-}
-
-#ifdef CONFIG_IMA_KEXEC
-/**
- * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
- *
- * Architectures should use this function to pass on the IMA buffer
- * information to the next kernel.
- *
- * Return: 0 on success, negative errno on error.
- */
-int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
-			      size_t size)
-{
-	image->arch.ima_buffer_addr = load_addr;
-	image->arch.ima_buffer_size = size;
-
-	return 0;
-}
-
-/**
- * setup_ima_buffer - add IMA buffer information to the fdt
- * @image:		kexec image being loaded.
- * @fdt:		Flattened device tree for the next kernel.
- * @chosen_node:	Offset to the chosen node.
- *
- * Return: 0 on success, or negative errno on error.
- */
-int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)
-{
-	int ret;
-
-	remove_ima_buffer(fdt, chosen_node);
-	if (!image->arch.ima_buffer_size)
-		return 0;
-
-	ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
-				       "linux,ima-kexec-buffer",
-				       image->arch.ima_buffer_addr,
-				       image->arch.ima_buffer_size);
-	if (ret)
-		return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);
-
-	ret = fdt_add_mem_rsv(fdt, image->arch.ima_buffer_addr,
-			      image->arch.ima_buffer_size);
-	if (ret)
-		return -EINVAL;
-
-	pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
-		 image->arch.ima_buffer_addr, image->arch.ima_buffer_size);
-
-	return 0;
-}
-#endif /* CONFIG_IMA_KEXEC */

drivers/of/kexec.c +107 -0

index 66787be081fe..a6ab35f16dd2 100644
@@ -10,10 +10,12 @@
  */
 
 #include <linux/kernel.h>
+#include <linux/slab.h>
 #include <linux/kexec.h>
 #include <linux/libfdt.h>
 #include <linux/of.h>
 #include <linux/of_fdt.h>
+#include <linux/memblock.h>
 #include <linux/random.h>
 #include <linux/types.h>
 

@@ -59,6 +61,141 @@ static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned lon
 	return -ENOENT;
 }
 
+/**
+ * get_addr_size_cells - Get address and size of root node
+ *
+ * @addr_cells: Return address of the root node
+ * @size_cells: Return size of the root node
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int get_addr_size_cells(int *addr_cells, int *size_cells)
+{
+	struct device_node *root;
+
+	root = of_find_node_by_path("/");
+	if (!root)
+		return -EINVAL;
+
+	*addr_cells = of_n_addr_cells(root);
+	*size_cells = of_n_size_cells(root);
+
+	of_node_put(root);
+
+	return 0;
+}
+
+/**
+ * do_get_kexec_buffer - Get address and size of device tree property
+ *
+ * @prop: Device tree property
+ * @len: Size of @prop
+ * @addr: Return address of the node
+ * @size: Return size of the node
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
+			       size_t *size)
+{
+	int ret, addr_cells, size_cells;
+
+	ret = get_addr_size_cells(&addr_cells, &size_cells);
+	if (ret)
+		return ret;
+
+	if (len < 4 * (addr_cells + size_cells))
+		return -ENOENT;
+
+	*addr = of_read_number(prop, addr_cells);
+	*size = of_read_number(prop + 4 * addr_cells, 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);
+}
+

drivers/of/kexec.c +9 -0

+{
+	int ret, len;
+	unsigned long addr;
+	size_t size;
+	const void *prop;
+
+	prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
+	if (!prop)
+		return;

drivers/of/kexec.c +11 -0

+
 /*
  * of_kexec_setup_new_fdt - modify /chosen and memory reservation for the next kernel
  *

@@ -219,6 +356,10 @@ int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
 	}
 
 	ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+	if (ret)
+		goto out;
+
+	ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
 
 out:
 	if (ret)

@@ -226,3 +367,60 @@ int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
 
 	return 0;
 }
+
+#ifdef CONFIG_IMA_KEXEC
+/**
+ * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
+ *
+ * @image: kimage struct to set IMA buffer data

drivers/of/kexec.c +6 -0

+{
+	image->arch.ima_buffer_addr = load_addr;
+	image->arch.ima_buffer_size = size;
+
+	return 0;
+}

drivers/of/kexec.c +25 -0

+{
+	int ret;
+
+	remove_ima_buffer(fdt, chosen_node);
+	if (!image->arch.ima_buffer_size)
+		return 0;
+
+	ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+				       "linux,ima-kexec-buffer",
+				       image->arch.ima_buffer_addr,
+				       image->arch.ima_buffer_size);
+	if (ret)
+		return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);
+
+	ret = fdt_add_mem_rsv(fdt, image->arch.ima_buffer_addr,
+			      image->arch.ima_buffer_size);
+	if (ret)
+		return -EINVAL;
+
+	pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
+		 image->arch.ima_buffer_addr, image->arch.ima_buffer_size);
+
+	return 0;
+}
+#endif /* CONFIG_IMA_KEXEC */

include/linux/of.h +0 -0

index 3375f5295875..7477f2266d8f 100644
@@ -562,6 +562,23 @@ struct kimage;
 int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
 			   unsigned long initrd_load_addr, unsigned long initrd_len,

include/linux/of.h +8 -0

+#else
+static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
+				   int chosen_node)
+{
+	remove_ima_buffer(fdt, chosen_node);
+	return 0;
+}
+#endif /* CONFIG_IMA_KEXEC */
 
 #else /* CONFIG_OF */
 

security/integrity/ima/ima.h +0 -4

index 6ebefec616e4..7c3947ad3773 100644
@@ -24,10 +24,6 @@
 
 #include "../integrity.h"
 
-#ifdef CONFIG_HAVE_IMA_KEXEC
-#include <asm/ima.h>
-#endif
-
 enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
 		     IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
 enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8, TPM_PCR10 = 10 };

security/integrity/ima/ima_kexec.c +2 -0

index 121de3e04af2..3d6a8820e2a5 100644
@@ -9,7 +9,9 @@
 
 #include <linux/seq_file.h>
 #include <linux/vmalloc.h>
+#include <linux/of.h>
 #include <linux/kexec.h>
+#include <linux/ima.h>
 #include "ima.h"
 
 #ifdef CONFIG_IMA_KEXEC

Signature · 1 line

2.29.2

Quoted 13 lines · Lakshmi Ramasubramanian

The functions defined in "arch/powerpc/kexec/ima.c" handle setting up and freeing the resources required to carry over the IMA measurement list from the current kernel to the next kernel across kexec system call. These functions do not have architecture specific code, but are currently limited to powerpc.

Move setup_ima_buffer() call into of_kexec_setup_new_fdt().

Move architecture independent functions from "arch/powerpc/kexec/ima.c" to "drivers/of/kexec.c". Delete "arch/powerpc/kexec/ima.c" and "arch/powerpc/include/asm/ima.h". Remove references to the deleted files in powerpc and in ima.

Quoted 2 lines

delete_fdt_mem_rsv() defined in "arch/powerpc/kexec/file_load.c" is not used anymore. Remove this function.

I think this patch should come first and then patch 1. Move then rework the code.

Quoted 148 lines

Signed-off-by Lakshmi Ramasubramanian <[email protected]>

---
  arch/powerpc/include/asm/ima.h     |  30 -----
  arch/powerpc/include/asm/kexec.h   |   1 -
  arch/powerpc/kexec/Makefile        |   7 -
  arch/powerpc/kexec/file_load.c     |  39 ------
  arch/powerpc/kexec/ima.c           | 182 --------------------------
  drivers/of/kexec.c                 | 198 +++++++++++++++++++++++++++++
  include/linux/of.h                 |  17 +++
  security/integrity/ima/ima.h       |   4 -
  security/integrity/ima/ima_kexec.c |   2 +
  9 files changed, 217 insertions(+), 263 deletions(-)

delete mode 100644 arch/powerpc/include/asm/ima.h delete mode 100644 arch/powerpc/kexec/ima.c

drivers/of/kexec.c +111 -0

index 66787be081fe..a6ab35f16dd2 100644
@@ -10,10 +10,12 @@
   */
 
  #include <linux/kernel.h>
+#include <linux/slab.h>
  #include <linux/kexec.h>
  #include <linux/libfdt.h>
  #include <linux/of.h>
  #include <linux/of_fdt.h>
+#include <linux/memblock.h>
  #include <linux/random.h>
  #include <linux/types.h>
 

@@ -59,6 +61,141 @@ static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned lon
  	return -ENOENT;
  }
 
+/**
+ * get_addr_size_cells - Get address and size of root node
+ *
+ * @addr_cells: Return address of the root node
+ * @size_cells: Return size of the root node
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int get_addr_size_cells(int *addr_cells, int *size_cells)
+{
+	struct device_node *root;
+
+	root = of_find_node_by_path("/");
+	if (!root)
+		return -EINVAL;
+
+	*addr_cells = of_n_addr_cells(root);
+	*size_cells = of_n_size_cells(root);
+
+	of_node_put(root);
+
+	return 0;
+}
+
+/**
+ * do_get_kexec_buffer - Get address and size of device tree property
+ *
+ * @prop: Device tree property
+ * @len: Size of @prop
+ * @addr: Return address of the node
+ * @size: Return size of the node
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
+			       size_t *size)
+{
+	int ret, addr_cells, size_cells;
+
+	ret = get_addr_size_cells(&addr_cells, &size_cells);
+	if (ret)
+		return ret;
+
+	if (len < 4 * (addr_cells + size_cells))
+		return -ENOENT;
+
+	*addr = of_read_number(prop, addr_cells);
+	*size = of_read_number(prop + 4 * addr_cells, 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);
+}
+
+/**
+ * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
+ *
+ * @fdt: Flattened Device Tree to update

drivers/of/kexec.c static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned lon · line 178

Quoted 6 lines

drivers/of/kexec.c +6 -0

+ * @chosen_node: Offset to the chosen node in the device tree
+ *
+ * The IMA measurement buffer is of no use to a subsequent kernel, so we always
+ * remove it from the device tree.
+ */
+void remove_ima_buffer(void *fdt, int chosen_node)

static

Quoted 14 lines

drivers/of/kexec.c +13 -0

+{
+	int ret, len;
+	unsigned long addr;
+	size_t size;
+	const void *prop;
+
+	prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
+	if (!prop)
+		return;
+
+	ret = do_get_kexec_buffer(prop, len, &addr, &size);
+	fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
+	if (ret)

drivers/of/kexec.c static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned lon · line 197

Quoted 6 lines

drivers/of/kexec.c +6 -0

+		return;
+
+	ret = fdt_find_and_del_mem_rsv(fdt, addr, size);
+	if (!ret)
+		pr_debug("Removed old IMA buffer reservation.\n");
+}

All the above needs to be in an '#ifdef CONFIG_IMA_KEXEC'.

Quoted 30 lines

drivers/of/kexec.c +15 -0

+
  /*
   * of_kexec_setup_new_fdt - modify /chosen and memory reservation for the next kernel
   *

@@ -219,6 +356,10 @@ int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
  	}
 
  	ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+	if (ret)
+		goto out;
+
+	ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
 
  out:
  	if (ret)

@@ -226,3 +367,60 @@ int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt,
 
  	return 0;
  }
+
+#ifdef CONFIG_IMA_KEXEC
+/**
+ * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
+ *
+ * @image: kimage struct to set IMA buffer data
+ * @load_addr: Starting address where IMA buffer is loaded at
+ * @size: Number of bytes in the IMA buffer
+ *
+ * Architectures should use this function to pass on the IMA buffer

drivers/of/kexec.c int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt, · line 385

Quoted 6 lines

drivers/of/kexec.c +6 -0

+ * information to the next kernel.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
+			      size_t size)

This should be a static inline in asm/kexec.h.

Quoted 11 lines

drivers/of/kexec.c +10 -0

+{
+	image->arch.ima_buffer_addr = load_addr;
+	image->arch.ima_buffer_size = size;
+
+	return 0;
+}
+
+/**
+ * setup_ima_buffer - add IMA buffer information to the fdt
+ * @image:		kexec image being loaded.

drivers/of/kexec.c int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt, · line 401

Quoted 6 lines

drivers/of/kexec.c +6 -0

+ * @fdt:		Flattened device tree for the next kernel.
+ * @chosen_node:	Offset to the chosen node.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node)

static

Quoted 37 lines

drivers/of/kexec.c +25 -0

+{
+	int ret;
+
+	remove_ima_buffer(fdt, chosen_node);
+	if (!image->arch.ima_buffer_size)
+		return 0;
+
+	ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
+				       "linux,ima-kexec-buffer",
+				       image->arch.ima_buffer_addr,
+				       image->arch.ima_buffer_size);
+	if (ret)
+		return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);
+
+	ret = fdt_add_mem_rsv(fdt, image->arch.ima_buffer_addr,
+			      image->arch.ima_buffer_size);
+	if (ret)
+		return -EINVAL;
+
+	pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
+		 image->arch.ima_buffer_addr, image->arch.ima_buffer_size);
+
+	return 0;
+}
+#endif /* CONFIG_IMA_KEXEC */

include/linux/of.h +3 -0

index 3375f5295875..7477f2266d8f 100644
@@ -562,6 +562,23 @@ 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);
+int ima_get_kexec_buffer(void **addr, size_t *size);
+int ima_free_kexec_buffer(void);
+void remove_ima_buffer(void *fdt, int chosen_node);

include/linux/of.h struct kimage; · line 573

Quoted 6 lines

include/linux/of.h +6 -0

+
+#ifdef CONFIG_IMA_KEXEC
+int arch_ima_add_kexec_buffer(struct kimage *image,
+			      unsigned long load_addr,
+			      size_t size);
+int setup_ima_buffer(const struct kimage *image, void *fdt, int chosen_node);

This doesn't need to be public.

Quoted 44 lines

include/linux/of.h +8 -0

+#else
+static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
+				   int chosen_node)
+{
+	remove_ima_buffer(fdt, chosen_node);
+	return 0;
+}
+#endif /* CONFIG_IMA_KEXEC */
 
  #else /* CONFIG_OF */
 

security/integrity/ima/ima.h +0 -4

index 6ebefec616e4..7c3947ad3773 100644
@@ -24,10 +24,6 @@
 
  #include "../integrity.h"
 
-#ifdef CONFIG_HAVE_IMA_KEXEC
-#include <asm/ima.h>
-#endif
-
  enum ima_show_type { IMA_SHOW_BINARY, IMA_SHOW_BINARY_NO_FIELD_LEN,
  		     IMA_SHOW_BINARY_OLD_STRING_FMT, IMA_SHOW_ASCII };
  enum tpm_pcrs { TPM_PCR0 = 0, TPM_PCR8 = 8, TPM_PCR10 = 10 };

security/integrity/ima/ima_kexec.c +2 -0

index 121de3e04af2..3d6a8820e2a5 100644
@@ -9,7 +9,9 @@
 
  #include <linux/seq_file.h>
  #include <linux/vmalloc.h>
+#include <linux/of.h>
  #include <linux/kexec.h>
+#include <linux/ima.h>
  #include "ima.h"
 
  #ifdef CONFIG_IMA_KEXEC

Signature · 1 line

2.29.2

Quoted 6 lines · Rob Herring

Quoted 5 lines · Lakshmi Ramasubramanian

The functions defined in "arch/powerpc/kexec/ima.c" handle setting up and freeing the resources required to carry over the IMA measurement list from the current kernel to the next kernel across kexec system call. These functions do not have architecture specific code, but are currently limited to powerpc.

Quoted 9 lines

Quoted 9 lines

drivers/of/kexec.c +9 -0

+#ifdef CONFIG_IMA_KEXEC
+/**
+ * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
+ *
+ * @image: kimage struct to set IMA buffer data
+ * @load_addr: Starting address where IMA buffer is loaded at
+ * @size: Number of bytes in the IMA buffer
+ *
+ * Architectures should use this function to pass on the IMA buffer

Quoted 8 lines

drivers/of/kexec.c int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt, · line 385

Quoted 6 lines

+ * information to the next kernel.
+ *
+ * Return: 0 on success, negative errno on error.
+ */

drivers/of/kexec.c +2 -0

+int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
+                          size_t size)

This should be a static inline in asm/kexec.h.

arch_ima_add_kexec_buffer() is identical for powerpc and arm64. Would it be better to "static inline" this function in "of.h" instead of duplicating it in "asm/kexec.h" for powerpc and arm64?

Quoted 8 lines · Lakshmi Ramasubramanian

Quoted 6 lines · Rob Herring

Quoted 5 lines · Lakshmi Ramasubramanian

The functions defined in "arch/powerpc/kexec/ima.c" handle setting up and freeing the resources required to carry over the IMA measurement list from the current kernel to the next kernel across kexec system call. These functions do not have architecture specific code, but are currently limited to powerpc.

[...]

Quoted 18 lines

Quoted 9 lines

Quoted 9 lines

drivers/of/kexec.c +9 -0

+#ifdef CONFIG_IMA_KEXEC
+/**
+ * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
+ *
+ * @image: kimage struct to set IMA buffer data
+ * @load_addr: Starting address where IMA buffer is loaded at
+ * @size: Number of bytes in the IMA buffer
+ *
+ * Architectures should use this function to pass on the IMA buffer

Quoted 8 lines

drivers/of/kexec.c int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt, · line 385

Quoted 6 lines

+ * information to the next kernel.
+ *
+ * Return: 0 on success, negative errno on error.
+ */

drivers/of/kexec.c +2 -0

+int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
+                          size_t size)

This should be a static inline in asm/kexec.h.

Quoted 3 lines

arch_ima_add_kexec_buffer() is identical for powerpc and arm64. Would it be better to "static inline" this function in "of.h" instead of duplicating it in "asm/kexec.h" for powerpc and arm64?

No, think about what it is specific to and place it there. It has nothing to do with DT really. All it is is a wrapper to access the struct members in kimage_arch. So it belongs where they are declared. Now perhaps ima_buffer_addr and ima_buffer_size shouldn't be arch specific, but that's a separate issue.

[...]

Quoted 18 lines

Quoted 9 lines

Quoted 9 lines

drivers/of/kexec.c +9 -0

+#ifdef CONFIG_IMA_KEXEC
+/**
+ * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
+ *
+ * @image: kimage struct to set IMA buffer data
+ * @load_addr: Starting address where IMA buffer is loaded at
+ * @size: Number of bytes in the IMA buffer
+ *
+ * Architectures should use this function to pass on the IMA buffer

Quoted 8 lines

drivers/of/kexec.c int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt, · line 385

Quoted 6 lines

+ * information to the next kernel.
+ *
+ * Return: 0 on success, negative errno on error.
+ */

drivers/of/kexec.c +2 -0

+int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
+                          size_t size)

This should be a static inline in asm/kexec.h.

Quoted 3 lines

arch_ima_add_kexec_buffer() is identical for powerpc and arm64. Would it be better to "static inline" this function in "of.h" instead of duplicating it in "asm/kexec.h" for powerpc and arm64?

No, think about what it is specific to and place it there. It has nothing to do with DT really. All it is is a wrapper to access the struct members in kimage_arch. So it belongs where they are declared. Now perhaps ima_buffer_addr and ima_buffer_size shouldn't be arch specific, but that's a separate issue.

Quoted 25 lines · Rob Herring

[...]

Quoted 18 lines

Quoted 9 lines

Quoted 9 lines

drivers/of/kexec.c +9 -0

+#ifdef CONFIG_IMA_KEXEC
+/**
+ * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
+ *
+ * @image: kimage struct to set IMA buffer data
+ * @load_addr: Starting address where IMA buffer is loaded at
+ * @size: Number of bytes in the IMA buffer
+ *
+ * Architectures should use this function to pass on the IMA buffer

Quoted 8 lines

drivers/of/kexec.c int of_kexec_setup_new_fdt(const struct kimage *image, void *fdt, · line 385

Quoted 6 lines

+ * information to the next kernel.
+ *
+ * Return: 0 on success, negative errno on error.
+ */

drivers/of/kexec.c +2 -0

+int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
+                          size_t size)

This should be a static inline in asm/kexec.h.

Quoted 3 lines

arch_ima_add_kexec_buffer() is identical for powerpc and arm64. Would it be better to "static inline" this function in "of.h" instead of duplicating it in "asm/kexec.h" for powerpc and arm64?

Quoted 6 lines

No, think about what it is specific to and place it there. It has nothing to do with DT really. All it is is a wrapper to access the struct members in kimage_arch. So it belongs where they are declared. Now perhaps ima_buffer_addr and ima_buffer_size shouldn't be arch specific, but that's a separate issue.

Since "struct kimage" definition is not available in "asm/kexec.h", defining arch_ima_add_kexec_buffer() in this header file results in the following build error:

./arch/powerpc/include/asm/kexec.h: In function 'arch_ima_add_kexec_buffer':
./arch/powerpc/include/asm/kexec.h:139:7: error: 'struct kimage' has no member named 'arch'
139 | image->arch.ima_buffer_addr = load_addr;

I think it would be appropriate to make arch_ima_add_kexec_buffer() a static inline function in "security/integrity/ima/ima_kexec.c" - the only file where this function is used.

create_dtb() function allocates memory for the device tree blob (DTB) and calls fdt_open_into(). If this call fails the memory allocated for the DTB is not freed before returning from create_dtb() thereby leaking memory.

Call vfree() to free the memory allocated for the DTB if fdt_open_into() fails.

Signed-off-by Lakshmi Ramasubramanian <[email protected]>

---
  arch/arm64/kernel/machine_kexec_file.c | 4 +++-
  1 file changed, 3 insertions(+), 1 deletion(-)

arch/arm64/kernel/machine_kexec_file.c +3 -1

index 7de9c47dee7c..3e045cd62451 100644
@@ -65,8 +65,10 @@ static int create_dtb(struct kimage *image,
 
  		/* duplicate a device tree blob */
  		ret = fdt_open_into(initial_boot_params, buf, buf_size);
-		if (ret)
+		if (ret) {
+			vfree(buf);
  			return -EINVAL;
+		}
 
  		ret = of_kexec_setup_new_fdt(image, buf, initrd_load_addr,
  					     initrd_len, cmdline);

Address and size of the buffer containing the IMA measurement log need to be passed from the current kernel to the next kernel on kexec.

Any existing "linux,ima-kexec-buffer" property in the device tree needs to be removed and its corresponding memory reservation in the currently running kernel needs to be freed. The address and size of the current kernel's IMA measurement log need to be added to the device tree's IMA kexec buffer node and memory for the buffer needs to be reserved for the log to be carried over to the next kernel on the kexec call.

Add address and size fields to "struct kimage_arch" for ARM64 platform to hold the address and size of the IMA measurement log buffer. Remove any existing "linux,ima-kexec-buffer" property in the device tree and free the corresponding memory reservation in the currently running kernel. Add "linux,ima-kexec-buffer" property to the device tree and reserve the memory for storing the IMA log that needs to be passed from the current kernel to the next one.

Update CONFIG_KEXEC_FILE to select CONFIG_HAVE_IMA_KEXEC to indicate that the IMA measurement log information is present in the device tree for ARM64.

Signed-off-by Lakshmi Ramasubramanian <[email protected]>

---
  arch/arm64/Kconfig             | 1 +
  arch/arm64/include/asm/kexec.h | 5 +++++
  2 files changed, 6 insertions(+)

arch/arm64/Kconfig +1 -0

index 1d466addb078..c85d18b1f2fd 100644
@@ -1094,6 +1094,7 @@ config KEXEC
  config KEXEC_FILE
  	bool "kexec file based system call"
  	select KEXEC_CORE
+	select HAVE_IMA_KEXEC
  	help
  	  This is new version of kexec system call. This system call is
  	  file based and takes file descriptors as system call argument

arch/arm64/include/asm/kexec.h +5 -0

index d24b527e8c00..2bd19ccb6c43 100644
@@ -100,6 +100,11 @@ struct kimage_arch {
  	void *elf_headers;
  	unsigned long elf_headers_mem;
  	unsigned long elf_headers_sz;
+
+#ifdef CONFIG_IMA_KEXEC
+	phys_addr_t ima_buffer_addr;
+	size_t ima_buffer_size;
+#endif
  };
 
  extern const struct kexec_file_ops kexec_image_ops;

On kexec file load Integrity Measurement Architecture (IMA) subsystem may verify the IMA signature of the kernel and initramfs, and measure it. The command line parameters passed to the kernel in the kexec call may also be measured by IMA. A remote attestation service can verify a TPM quote based on the TPM event log, the IMA measurement list, and the TPM PCR data. This can be achieved only if the IMA measurement log is carried over from the current kernel to the next kernel across the kexec call.

powerpc already supports carrying forward the IMA measurement log on kexec. This patch set adds support for carrying forward the IMA measurement log on kexec on ARM64.

This patch set moves the platform independent code defined for powerpc such that it can be reused for other platforms as well. A chosen node "linux,ima-kexec-buffer" is added to the DTB for ARM64 to hold the address and the size of the memory reserved to carry the IMA measurement log.

This patch set has been tested for ARM64 platform using QEMU. I would like help from the community for testing this change on powerpc. Thanks.

This patch set is based on
commit a29a64445089 ("powerpc: Use common of_kexec_setup_new_fdt()") in https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git
"dt/kexec" branch.

Quoted 1 line

Changelog:

v12
- Use fdt_appendprop_addrrange() in setup_ima_buffer() to setup the IMA measurement list property in the device tree.
- Moved architecture independent functions from "arch/powerpc/kexec/ima.c" to "drivers/of/kexec."
- Deleted "arch/powerpc/kexec/ima.c" and "arch/powerpc/include/asm/ima.h".

v11
- Rebased the changes on the kexec code refactoring done by Rob Herring in his "dt/kexec" branch
- Removed "extern" keyword in function declarations
- Removed unnecessary header files included in C files
- Updated patch descriptions per Thiago's comments

v10
- Moved delete_fdt_mem_rsv(), remove_ima_buffer(), get_ima_kexec_buffer, and get_root_addr_size_cells() to drivers/of/kexec.c
- Moved arch_ima_add_kexec_buffer() to security/integrity/ima/ima_kexec.c
- Conditionally define IMA buffer fields in struct kimage_arch

v9
- Moved delete_fdt_mem_rsv() to drivers/of/kexec_fdt.c
- Defined a new function get_ima_kexec_buffer() in drivers/of/ima_kexec.c to replace do_get_kexec_buffer()
- Changed remove_ima_kexec_buffer() to the original function name remove_ima_buffer()
- Moved remove_ima_buffer() to drivers/of/ima_kexec.c
- Moved ima_get_kexec_buffer() and ima_free_kexec_buffer() to security/integrity/ima/ima_kexec.c

v8:
- Moved remove_ima_kexec_buffer(), do_get_kexec_buffer(), and delete_fdt_mem_rsv() to drivers/of/fdt.c
- Moved ima_dump_measurement_list() and ima_add_kexec_buffer() back to security/integrity/ima/ima_kexec.c

v7:
- Renamed remove_ima_buffer() to remove_ima_kexec_buffer() and moved this function definition to kernel.
- Moved delete_fdt_mem_rsv() definition to kernel
- Moved ima_dump_measurement_list() and ima_add_kexec_buffer() to a new file namely ima_kexec_fdt.c in IMA

v6:
- Remove any existing FDT_PROP_IMA_KEXEC_BUFFER property in the device tree and also its corresponding memory reservation in the currently running kernel.
- Moved the function remove_ima_buffer() defined for powerpc to IMA and renamed the function to ima_remove_kexec_buffer(). Also, moved delete_fdt_mem_rsv() from powerpc to IMA.

v5:
- Merged get_addr_size_cells() and do_get_kexec_buffer() into a single function when moving the arch independent code from powerpc to IMA
- Reverted the change to use FDT functions in powerpc code and added back the original code in get_addr_size_cells() and do_get_kexec_buffer() for powerpc.
- Added fdt_add_mem_rsv() for ARM64 to reserve the memory for the IMA log buffer during kexec.
- Fixed the warning reported by kernel test bot for ARM64 arch_ima_add_kexec_buffer() - moved this function to a new file namely arch/arm64/kernel/ima_kexec.c

v4:
- Submitting the patch series on behalf of the original author Prakhar Srivastava <[email protected]>
- Moved FDT_PROP_IMA_KEXEC_BUFFER ("linux,ima-kexec-buffer") to libfdt.h so that it can be shared by multiple platforms.

v3:
Breakup patches further into separate patches.
- Refactoring non architecture specific code out of powerpc
- Update powerpc related code to use fdt functions
- Update IMA buffer read related code to use of functions
- Add support to store the memory information of the IMA measurement logs to be carried forward.
- Update the property strings to align with documented nodes
https://github.com/devicetree-org/dt-schema/pull/46

v2:
Break patches into separate patches.
- Powerpc related Refactoring
- Updating the docuemntation for chosen node
- Updating arm64 to support IMA buffer pass

v1:
Refactoring carrying over IMA measuremnet logs over Kexec. This patch
moves the non-architecture specific code out of powerpc and adds to security/ima.(Suggested by Thiago)
Add Documentation regarding the ima-kexec-buffer node in the chosen
node documentation

v0:
Add a layer of abstraction to use the memory reserved by device tree
for ima buffer pass.
Add support for ima buffer pass using reserved memory for arm64 kexec.
Update the arch sepcific code path in kexec file load to store the ima buffer in the reserved memory. The same reserved memory is read on kexec or cold boot.

Lakshmi Ramasubramanian (4):
powerpc: Use fdt_appendprop_addrrange() to add ima buffer to FDT
powerpc: Move arch independent ima kexec functions to
drivers/of/kexec.c
arm64: Free DTB buffer if fdt_open_into() fails
arm64: Add IMA log information in kimage used for kexec

  arch/arm64/Kconfig                     |   1 +
  arch/arm64/include/asm/kexec.h         |   5 +
  arch/arm64/kernel/machine_kexec_file.c |   4 +-
  arch/powerpc/include/asm/ima.h         |  30 ----
  arch/powerpc/include/asm/kexec.h       |   1 -
  arch/powerpc/kexec/Makefile            |   7 -
  arch/powerpc/kexec/file_load.c         |  39 -----
  arch/powerpc/kexec/ima.c               | 219 -------------------------
  drivers/of/kexec.c                     | 198 ++++++++++++++++++++++
  include/linux/of.h                     |  17 ++
  security/integrity/ima/ima.h           |   4 -
  security/integrity/ima/ima_kexec.c     |   2 +
  12 files changed, 226 insertions(+), 301 deletions(-)

delete mode 100644 arch/powerpc/include/asm/ima.h delete mode 100644 arch/powerpc/kexec/ima.c