So far binfmt_flat has onl been supported on 32-bit platforms, so the
variable size of the fields didn't matter.  But the upcoming RISC-V
nommu port supports 64-bit CPUs, and we now have a conflict between
the elf2flt creation tool that always uses 32-bit fields and the kernel
that uses (unsigned) long field.  Switch to the userspace view as the
rest of the binfmt_flat format is completely architecture neutral,
and binfmt_flat isn't the right binary format for huge executables to
start with.

While we're at it also ensure these fields are using __be types as
they big endian and are byteswapped when loaded.

Signed-off-by: Christoph Hellwig <h...@lst.de>

wip
---
 include/linux/flat.h | 48 ++++++++++++++++++++++----------------------
 1 file changed, 24 insertions(+), 24 deletions(-)

diff --git a/include/linux/flat.h b/include/linux/flat.h
index 21d901ba191b..59e892d5fadb 100644
--- a/include/linux/flat.h
+++ b/include/linux/flat.h
@@ -24,26 +24,26 @@
  */
 
 struct flat_hdr {
-       char magic[4];
-       unsigned long rev;          /* version (as above) */
-       unsigned long entry;        /* Offset of first executable instruction
-                                      with text segment from beginning of file 
*/
-       unsigned long data_start;   /* Offset of data segment from beginning of
-                                      file */
-       unsigned long data_end;     /* Offset of end of data segment
-                                      from beginning of file */
-       unsigned long bss_end;      /* Offset of end of bss segment from 
beginning
-                                      of file */
+       char    magic[4];
+       __be32  rev;          /* version (as above) */
+       __be32  entry;        /* Offset of first executable instruction
+                                with text segment from beginning of file */
+       __be32  data_start;   /* Offset of data segment from beginning of
+                                file */
+       __be32  data_end;     /* Offset of end of data segment from beginning
+                                of file */
+       __be32  bss_end;      /* Offset of end of bss segment from beginning
+                                of file */
 
        /* (It is assumed that data_end through bss_end forms the bss segment.) 
*/
 
-       unsigned long stack_size;   /* Size of stack, in bytes */
-       unsigned long reloc_start;  /* Offset of relocation records from
-                                      beginning of file */
-       unsigned long reloc_count;  /* Number of relocation records */
-       unsigned long flags;
-       unsigned long build_date;   /* When the program/library was built */
-       unsigned long filler[5];    /* Reservered, set to zero */
+       __be32  stack_size;   /* Size of stack, in bytes */
+       __be32  reloc_start;  /* Offset of relocation records from beginning of
+                                file */
+       __be32  reloc_count;  /* Number of relocation records */
+       __be32  flags;
+       __be32  build_date;   /* When the program/library was built */
+       __u32   filler[5];    /* Reservered, set to zero */
 };
 
 #define FLAT_FLAG_RAM    0x0001 /* load program entirely into RAM */
@@ -67,19 +67,19 @@ struct flat_hdr {
 #define OLD_FLAT_RELOC_TYPE_BSS                2
 
 typedef union {
-       unsigned long   value;
+       u32             value;
        struct {
 # if defined(mc68000) && !defined(CONFIG_COLDFIRE)
-               signed long offset : 30;
-               unsigned long type : 2;
+               s32     offset : 30;
+               u32     type : 2;
 #      define OLD_FLAT_FLAG_RAM    0x1 /* load program entirely into RAM */
 # elif defined(__BIG_ENDIAN_BITFIELD)
-               unsigned long type : 2;
-               signed long offset : 30;
+               u32     type : 2;
+               s32     offset : 30;
 #      define OLD_FLAT_FLAG_RAM    0x1 /* load program entirely into RAM */
 # elif defined(__LITTLE_ENDIAN_BITFIELD)
-               signed long offset : 30;
-               unsigned long type : 2;
+               s32     offset : 30;
+               u32     type : 2;
 #      define OLD_FLAT_FLAG_RAM    0x1 /* load program entirely into RAM */
 # else
 #      error "Unknown bitfield order for flat files."
-- 
2.20.1

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