Re: [PATCH v17 05/10] powerpc: Move ima buffer fields to struct kimage

On 2/10/21 9:20 AM, Rob Herring wrote:

On Tue, Feb 09, 2021 at 10:21:55AM -0800, Lakshmi Ramasubramanian wrote:

quoted

The fields ima_buffer_addr and ima_buffer_size in "struct kimage_arch"
for powerpc are used to carry forward the IMA measurement list across
kexec system call.  These fields are not architecture specific, but are
currently limited to powerpc.

arch_ima_add_kexec_buffer() defined in "arch/powerpc/kexec/ima.c"
sets ima_buffer_addr and ima_buffer_size for the kexec system call.
This function does not have architecture specific code, but is
currently limited to powerpc.

Move ima_buffer_addr and ima_buffer_size to "struct kimage".
Rename arch_ima_add_kexec_buffer() to of_ima_add_kexec_buffer()
and move it in drivers/of/kexec.c.

Co-developed-by: Prakhar Srivastava <redacted>
Signed-off-by: Prakhar Srivastava <redacted>
Signed-off-by: Lakshmi Ramasubramanian <redacted>
Suggested-by: Will Deacon <will@kernel.org>
---
  arch/powerpc/include/asm/ima.h     |  3 ---
  arch/powerpc/include/asm/kexec.h   |  5 -----
  arch/powerpc/kexec/ima.c           | 29 ++++++-----------------------
  drivers/of/kexec.c                 | 23 +++++++++++++++++++++++
  include/linux/kexec.h              |  3 +++
  include/linux/of.h                 |  5 +++++
  security/integrity/ima/ima_kexec.c |  3 ++-
  7 files changed, 39 insertions(+), 32 deletions(-)

quoted

diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
index 469e09613cdd..9f33d215b9f2 100644
--- a/drivers/of/kexec.c
+++ b/drivers/of/kexec.c

@@ -63,6 +63,29 @@ static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned lon
  	return -ENOENT;
  }
  
+#ifdef CONFIG_IMA_KEXEC
+/**
+ * of_ima_add_kexec_buffer - Add IMA buffer for next kernel
+ *
+ * @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
+ *
+ * Use this function to pass on the IMA buffer information to
+ * the next kernel across kexec system call.
+ *
+ * Return: 0 on success, negative errno on error.
+ */
+int of_ima_add_kexec_buffer(struct kimage *image,
+			    unsigned long load_addr, size_t size)
+{
+	image->ima_buffer_addr = load_addr;
+	image->ima_buffer_size = size;
+

There's nothing DT specific about this function, so this is the wrong
place for it. I would just remove it and directly set the members.

Will do.

  -lakshmi