[PATCH v3 2/2] update powerpc implementation to call into of_ima*

From: Prakhar Srivastava
Date: Wed Oct 09 2019 - 20:13:06 EST


update powerpc ima buffer pass implementationt to call into
of_ima* for a cross architecture support.

Signed-off-by: Prakhar Srivastava <prsriva@xxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/include/asm/ima.h | 6 --
arch/powerpc/kernel/Makefile | 8 +-
arch/powerpc/kernel/ima_kexec.c | 170 +++-----------------------------
3 files changed, 16 insertions(+), 168 deletions(-)

diff --git a/arch/powerpc/include/asm/ima.h b/arch/powerpc/include/asm/ima.h
index ead488cf3981..5ecff8896eed 100644
--- a/arch/powerpc/include/asm/ima.h
+++ b/arch/powerpc/include/asm/ima.h
@@ -6,12 +6,7 @@ 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,
@@ -26,5 +21,4 @@ static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
return 0;
}
#endif /* CONFIG_IMA_KEXEC */
-
#endif /* _ASM_POWERPC_IMA_H */
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index 56dfa7a2a6f2..6a3d8fd6f1df 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -126,12 +126,8 @@ obj-$(CONFIG_PCI) += pci_$(BITS).o $(pci64-y) \
obj-$(CONFIG_PCI_MSI) += msi.o
obj-$(CONFIG_KEXEC_CORE) += machine_kexec.o crash.o \
machine_kexec_$(BITS).o
-obj-$(CONFIG_KEXEC_FILE) += machine_kexec_file_$(BITS).o kexec_elf_$(BITS).o
-ifdef CONFIG_HAVE_IMA_KEXEC
-ifdef CONFIG_IMA
-obj-y += ima_kexec.o
-endif
-endif
+obj-$(CONFIG_KEXEC_FILE) += machine_kexec_file_$(BITS).o kexec_elf_$(BITS).o \
+ ima_kexec.o

obj-$(CONFIG_AUDIT) += audit.o
obj64-$(CONFIG_AUDIT) += compat_audit.o
diff --git a/arch/powerpc/kernel/ima_kexec.c b/arch/powerpc/kernel/ima_kexec.c
index 720e50e490b6..41f52297de0c 100644
--- a/arch/powerpc/kernel/ima_kexec.c
+++ b/arch/powerpc/kernel/ima_kexec.c
@@ -6,45 +6,21 @@
* Thiago Jung Bauermann <bauerman@xxxxxxxxxxxxxxxxxx>
*/

-#include <linux/slab.h>
#include <linux/kexec.h>
#include <linux/of.h>
-#include <linux/memblock.h>
-#include <linux/libfdt.h>

-static int get_addr_size_cells(int *addr_cells, int *size_cells)
+/**
+ * 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)
{
- 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;
+ fdt_remove_ima_buffer(fdt, chosen_node);
+ return;
}

-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
@@ -55,23 +31,7 @@ static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
*/
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;
+ return of_get_ima_buffer(addr, size);
}

/**
@@ -79,52 +39,7 @@ int ima_get_kexec_buffer(void **addr, size_t *size)
*/
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");
+ return of_remove_ima_buffer();
}

#ifdef CONFIG_IMA_KEXEC
@@ -145,27 +60,6 @@ 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.
@@ -176,44 +70,8 @@ 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];
-
- remove_ima_buffer(fdt, chosen_node);
- if (!image->arch.ima_buffer_size)
- return 0;
-
- ret = get_addr_size_cells(&addr_cells, &size_cells);
- 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;
-
- 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;
+ return fdt_setup_ima_buffer(image->arch.ima_buffer_addr,
+ image->arch.ima_buffer_size,
+ fdt, chosen_node);
}
#endif /* CONFIG_IMA_KEXEC */
--
2.17.1