Le 13/10/2021 à 09:01, Kees Cook a écrit :

On Mon, Oct 11, 2021 at 05:25:32PM +0200, Christophe Leroy wrote:

quoted

We have three architectures using function descriptors, each with its
own name.

Add a common typedef that can be used in generic code.

Also add a stub typedef for architecture without function descriptors,

nit: funct_descr_t reads weird to me. why not func_desc_t ? Either way:

func_desc_t already exists in powerpc. I have a patch to remove it as it 
is redundant with struct ppc64_opd_entry, but I didnt' want to include 
it in this series.

But after all I can add it in this series, I'll add it in v2.

Christophe

Reviewed-by: Kees Cook <redacted>

quoted

to avoid a forest of #ifdefs.

Signed-off-by: Christophe Leroy <redacted>
---
  arch/ia64/include/asm/sections.h    | 1 +
  arch/parisc/include/asm/sections.h  | 1 +
  arch/powerpc/include/asm/sections.h | 1 +
  include/asm-generic/sections.h      | 3 +++
  4 files changed, 6 insertions(+)

diff --git a/arch/ia64/include/asm/sections.h b/arch/ia64/include/asm/sections.h
index 80f5868afb06..929b5c535620 100644
--- a/arch/ia64/include/asm/sections.h
+++ b/arch/ia64/include/asm/sections.h

@@ -8,6 +8,7 @@
   */
  
  #define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1
+typedef struct fdesc funct_descr_t;
  
  #include <linux/elf.h>
  #include <linux/uaccess.h>

diff --git a/arch/parisc/include/asm/sections.h b/arch/parisc/include/asm/sections.h
index 2e781ee19b66..329e80f7af0a 100644
--- a/arch/parisc/include/asm/sections.h
+++ b/arch/parisc/include/asm/sections.h

@@ -4,6 +4,7 @@
  
  #ifdef CONFIG_64BIT
  #define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1
+typedef Elf64_Fdesc funct_descr_t;
  #endif
  
  /* nothing to see, move along */

diff --git a/arch/powerpc/include/asm/sections.h b/arch/powerpc/include/asm/sections.h
index b7f1ba04e756..d0d5287fa568 100644
--- a/arch/powerpc/include/asm/sections.h
+++ b/arch/powerpc/include/asm/sections.h

@@ -10,6 +10,7 @@
  
  #ifdef PPC64_ELF_ABI_v1
  #define HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR 1
+typedef struct ppc64_opd_entry funct_descr_t;
  #endif
  
  #include <asm-generic/sections.h>

diff --git a/include/asm-generic/sections.h b/include/asm-generic/sections.h
index 1db5cfd69817..436412d94054 100644
--- a/include/asm-generic/sections.h
+++ b/include/asm-generic/sections.h

@@ -63,6 +63,9 @@ extern __visible const void __nosave_begin, __nosave_end;
  #else
  #define dereference_function_descriptor(p) ((void *)(p))
  #define dereference_kernel_function_descriptor(p) ((void *)(p))
+typedef struct {
+	unsigned long addr;
+} funct_descr_t;
  #endif
  
  /* random extra sections (if any).  Override

-- 
2.31.1