Allow modules in ROM From: Pavel Roskin ChangeLog: * include/grub/dl.h: Include grub/elf.h. (struct grub_dl): Add symtab field. * kern/dl.c [GRUB_MACHINE_QEMU]: Define GRUB_MODULES_MACHINE_READONLY. (grub_dl_resolve_symbols): Populate mod->symtab, making a copy of the header for read-only modules. (grub_dl_unload): Free mod->symtab for read-only modules. * kern/i386/dl.c: Use mod->symtab. * kern/powerpc/dl.c: Likewise. * kern/sparc64/dl.c: Likewise. * kern/x86_64/dl.c: Likewise. --- include/grub/dl.h | 4 +++- kern/dl.c | 19 +++++++++++++++++-- kern/i386/dl.c | 4 +--- kern/powerpc/dl.c | 4 +--- kern/sparc64/dl.c | 4 +--- kern/x86_64/dl.c | 4 +--- 6 files changed, 24 insertions(+), 15 deletions(-) diff --git a/include/grub/dl.h b/include/grub/dl.h index 894da1d..bebb810 100644 --- a/include/grub/dl.h +++ b/include/grub/dl.h @@ -1,7 +1,7 @@ /* dl.h - types and prototypes for loadable module support */ /* * GRUB -- GRand Unified Bootloader - * Copyright (C) 2002,2004,2005,2007,2008 Free Software Foundation, Inc. + * Copyright (C) 2002,2004,2005,2007,2008,2009 Free Software Foundation, Inc. * * GRUB is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -23,6 +23,7 @@ #include #include #include +#include #define GRUB_MOD_INIT(name) \ static void grub_mod_init (grub_dl_t mod __attribute__ ((unused))) __attribute__ ((used)); \ @@ -78,6 +79,7 @@ struct grub_dl int ref_count; grub_dl_dep_t dep; grub_dl_segment_t segment; + Elf_Sym *symtab; void (*init) (struct grub_dl *mod); void (*fini) (void); }; diff --git a/kern/dl.c b/kern/dl.c index cd34e31..af4e5aa 100644 --- a/kern/dl.c +++ b/kern/dl.c @@ -1,7 +1,7 @@ /* dl.c - loadable module support */ /* * GRUB -- GRand Unified Bootloader - * Copyright (C) 2002,2003,2004,2005,2007,2008 Free Software Foundation, Inc. + * Copyright (C) 2002,2003,2004,2005,2007,2008,2009 Free Software Foundation, Inc. * * GRUB is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -28,6 +28,12 @@ #include #include #include +#include + +/* Platforms where modules are in a readonly area of memory. */ +#if defined(GRUB_MACHINE_QEMU) +#define GRUB_MODULES_MACHINE_READONLY +#endif @@ -309,7 +315,13 @@ grub_dl_resolve_symbols (grub_dl_t mod, Elf_Ehdr *e) if (i == e->e_shnum) return grub_error (GRUB_ERR_BAD_MODULE, "no symbol table"); - sym = (Elf_Sym *) ((char *) e + s->sh_offset); +#ifdef GRUB_MODULES_MACHINE_READONLY + mod->symtab = grub_malloc (s->sh_size); + memcpy (mod->symtab, (char *) e + s->sh_offset, s->sh_size); +#else + mod->symtab = (Elf_Sym *) ((char *) e + s->sh_offset); +#endif + sym = mod->symtab; size = s->sh_size; entsize = s->sh_entsize; @@ -671,6 +683,9 @@ grub_dl_unload (grub_dl_t mod) } grub_free (mod->name); +#ifdef GRUB_MODULES_MACHINE_READONLY + grub_free (mod->symtab); +#endif grub_free (mod); return 1; } diff --git a/kern/i386/dl.c b/kern/i386/dl.c index 978bfb1..a17f175 100644 --- a/kern/i386/dl.c +++ b/kern/i386/dl.c @@ -43,7 +43,6 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr) { Elf32_Ehdr *e = ehdr; Elf32_Shdr *s; - Elf32_Sym *symtab; Elf32_Word entsize; unsigned i; @@ -57,7 +56,6 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr) if (i == e->e_shnum) return grub_error (GRUB_ERR_BAD_MODULE, "no symtab found"); - symtab = (Elf32_Sym *) ((char *) e + s->sh_offset); entsize = s->sh_entsize; for (i = 0, s = (Elf32_Shdr *) ((char *) e + e->e_shoff); @@ -89,7 +87,7 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr) "reloc offset is out of the segment"); addr = (Elf32_Word *) ((char *) seg->addr + rel->r_offset); - sym = (Elf32_Sym *) ((char *) symtab + sym = (Elf32_Sym *) ((char *) mod->symtab + entsize * ELF32_R_SYM (rel->r_info)); switch (ELF32_R_TYPE (rel->r_info)) diff --git a/kern/powerpc/dl.c b/kern/powerpc/dl.c index ae987c0..9b1cb14 100644 --- a/kern/powerpc/dl.c +++ b/kern/powerpc/dl.c @@ -44,7 +44,6 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr) { Elf32_Ehdr *e = ehdr; Elf32_Shdr *s; - Elf32_Sym *symtab; Elf32_Word entsize; unsigned i; @@ -58,7 +57,6 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr) if (i == e->e_shnum) return grub_error (GRUB_ERR_BAD_MODULE, "no symtab found"); - symtab = (Elf32_Sym *) ((char *) e + s->sh_offset); entsize = s->sh_entsize; for (i = 0, s = (Elf32_Shdr *) ((char *) e + e->e_shoff); @@ -91,7 +89,7 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr) "reloc offset is out of the segment"); addr = (Elf32_Word *) ((char *) seg->addr + rel->r_offset); - sym = (Elf32_Sym *) ((char *) symtab + sym = (Elf32_Sym *) ((char *) mod->symtab + entsize * ELF32_R_SYM (rel->r_info)); /* On the PPC the value does not have an explicit diff --git a/kern/sparc64/dl.c b/kern/sparc64/dl.c index d998daf..5334896 100644 --- a/kern/sparc64/dl.c +++ b/kern/sparc64/dl.c @@ -44,7 +44,6 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr) { Elf64_Ehdr *e = ehdr; Elf64_Shdr *s; - Elf64_Sym *symtab; Elf64_Word entsize; unsigned i; @@ -58,7 +57,6 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr) if (i == e->e_shnum) return grub_error (GRUB_ERR_BAD_MODULE, "no symtab found"); - symtab = (Elf64_Sym *) ((char *) e + s->sh_offset); entsize = s->sh_entsize; for (i = 0, s = (Elf64_Shdr *) ((char *) e + e->e_shoff); @@ -91,7 +89,7 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr) "reloc offset is out of the segment"); addr = (Elf64_Word *) ((char *) seg->addr + rel->r_offset); - sym = (Elf64_Sym *) ((char *) symtab + sym = (Elf64_Sym *) ((char *) mod->symtab + entsize * ELF64_R_SYM (rel->r_info)); value = sym->st_value + rel->r_addend; diff --git a/kern/x86_64/dl.c b/kern/x86_64/dl.c index a606901..9e5de6e 100644 --- a/kern/x86_64/dl.c +++ b/kern/x86_64/dl.c @@ -43,7 +43,6 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr) { Elf64_Ehdr *e = ehdr; Elf64_Shdr *s; - Elf64_Sym *symtab; Elf64_Word entsize; unsigned i; @@ -57,7 +56,6 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr) if (i == e->e_shnum) return grub_error (GRUB_ERR_BAD_MODULE, "no symtab found"); - symtab = (Elf64_Sym *) ((char *) e + s->sh_offset); entsize = s->sh_entsize; for (i = 0, s = (Elf64_Shdr *) ((char *) e + e->e_shoff); @@ -91,7 +89,7 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr) addr32 = (Elf64_Word *) ((char *) seg->addr + rel->r_offset); addr64 = (Elf64_Xword *) addr32; - sym = (Elf64_Sym *) ((char *) symtab + sym = (Elf64_Sym *) ((char *) mod->symtab + entsize * ELF64_R_SYM (rel->r_info)); switch (ELF64_R_TYPE (rel->r_info))