On Mon, 17 Apr 2006 17:27:42 +0100, Thiemo Seufer <ths@xxxxxxxxxxxx> wrote:
> So it is the
>
> r.r_info = TO_NATIVE(rela->r_info);
>
> in modpost.c which breaks both SYM and TYPE because it assumes a
> 64bit integer. The proper solution would be to add a Elf64_Mips_Rela
> structure (with lots of nearly identical duplicated code), the hack
> would be to cast r_info to a 32bit integer for mips, before feeding
> it to TO_NATIVE (which works until somebody asks for the TYPE, then
> a separate mips64 version becomes inevitable.)
I'd like to fix in _proper_ way. Please review. Thanks.
64bit mips has different r_info layout. This patch fixes modpost
segfault for 64bit little endian mips kernel.
Signed-off-by: Atsushi Nemoto <anemo@xxxxxxxxxxxxx>
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index cd00e9f..4ce95c6 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -710,7 +710,20 @@ static void check_sec_ref(struct module
Elf_Rela r;
const char *secname;
r.r_offset = TO_NATIVE(rela->r_offset);
+#if KERNEL_ELFCLASS == ELFCLASS64
+ if (hdr->e_machine == EM_MIPS) {
+ unsigned int r_sym =
+ ELF64_MIPS_R_SYM(rela->r_info);
+ unsigned int r_type =
+ ELF64_MIPS_R_TYPE(rela->r_info);
+ r.r_info = ELF_R_INFO(TO_NATIVE(r_sym),
+ TO_NATIVE(r_type));
+ } else {
+ r.r_info = TO_NATIVE(rela->r_info);
+ }
+#else
r.r_info = TO_NATIVE(rela->r_info);
+#endif
r.r_addend = TO_NATIVE(rela->r_addend);
sym = elf->symtab_start + ELF_R_SYM(r.r_info);
/* Skip special sections */
diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
index b14255c..7d1c04d 100644
--- a/scripts/mod/modpost.h
+++ b/scripts/mod/modpost.h
@@ -24,6 +24,7 @@
#define Elf_Rela Elf32_Rela
#define ELF_R_SYM ELF32_R_SYM
#define ELF_R_TYPE ELF32_R_TYPE
+#define ELF_R_INFO ELF32_R_INFO
#else
#define Elf_Ehdr Elf64_Ehdr
@@ -37,8 +38,43 @@
#define Elf_Rela Elf64_Rela
#define ELF_R_SYM ELF64_R_SYM
#define ELF_R_TYPE ELF64_R_TYPE
+#define ELF_R_INFO ELF64_R_INFO
#endif
+/* The 64-bit MIPS ELF ABI uses an unusual reloc format. */
+typedef struct
+{
+ Elf32_Word r_sym; /* Symbol index */
+ unsigned char r_ssym; /* Special symbol for 2nd relocation */
+ unsigned char r_type3; /* 3rd relocation type */
+ unsigned char r_type2; /* 2nd relocation type */
+ unsigned char r_type1; /* 1st relocation type */
+} _Elf64_Mips_R_Info;
+
+typedef union
+{
+ Elf64_Xword r_info_number;
+ _Elf64_Mips_R_Info r_info_fields;
+} _Elf64_Mips_R_Info_union;
+
+typedef struct
+{
+ Elf64_Addr r_offset; /* Address */
+ _Elf64_Mips_R_Info_union r_info; /* Relocation type and symbol index */
+ Elf64_Sxword r_addend; /* Addend */
+} Elf64_Mips_Rela;
+
+#define ELF64_MIPS_R_SYM(i) \
+ ((__extension__ (_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_sym)
+#define ELF64_MIPS_R_TYPE(i) \
+ (((_Elf64_Mips_R_Info_union)(i)).r_info_fields.r_type1 \
+ | ((Elf32_Word)(__extension__ (_Elf64_Mips_R_Info_union)(i) \
+ ).r_info_fields.r_type2 << 8) \
+ | ((Elf32_Word)(__extension__ (_Elf64_Mips_R_Info_union)(i) \
+ ).r_info_fields.r_type3 << 16) \
+ | ((Elf32_Word)(__extension__ (_Elf64_Mips_R_Info_union)(i) \
+ ).r_info_fields.r_ssym << 24))
+
#if KERNEL_ELFDATA != HOST_ELFDATA
static inline void __endian(const void *src, void *dest, unsigned int size)
