2 * Written 2000,2002 by Andi Kleen.
4 * Loosely based on the sparc64 and IA64 32bit emulation loaders.
5 * This tricks binfmt_elf.c into loading 32bit binaries using lots
6 * of ugly preprocessor tricks. Talk about very very poor man's inheritance.
8 #include <linux/types.h>
9 #include <linux/stddef.h>
10 #include <linux/rwsem.h>
11 #include <linux/sched.h>
12 #include <linux/compat.h>
13 #include <linux/string.h>
14 #include <linux/binfmts.h>
16 #include <linux/security.h>
18 #include <asm/segment.h>
19 #include <asm/ptrace.h>
20 #include <asm/processor.h>
21 #include <asm/user32.h>
22 #include <asm/sigcontext32.h>
23 #include <asm/fpu32.h>
25 #include <asm/uaccess.h>
27 #include <asm/vsyscall32.h>
29 #define ELF_NAME "elf/i386"
32 #define AT_SYSINFO_EHDR 33
34 int sysctl_vsyscall32
= 1;
36 #define ARCH_DLINFO do { \
37 if (sysctl_vsyscall32) { \
38 NEW_AUX_ENT(AT_SYSINFO, (u32)(u64)VSYSCALL32_VSYSCALL); \
39 NEW_AUX_ENT(AT_SYSINFO_EHDR, VSYSCALL32_BASE); \
46 #define IA32_EMULATOR 1
48 #define ELF_ET_DYN_BASE (TASK_UNMAPPED_BASE + 0x1000000)
51 #define ELF_ARCH EM_386
54 #define ELF_CLASS ELFCLASS32
56 #define ELF_DATA ELFDATA2LSB
58 #define USE_ELF_CORE_DUMP 1
60 /* Override elfcore.h */
61 #define _LINUX_ELFCORE_H 1
62 typedef unsigned int elf_greg_t
;
64 #define ELF_NGREG (sizeof (struct user_regs_struct32) / sizeof(elf_greg_t))
65 typedef elf_greg_t elf_gregset_t
[ELF_NGREG
];
68 * These macros parameterize elf_core_dump in fs/binfmt_elf.c to write out
69 * extra segments containing the vsyscall DSO contents. Dumping its
70 * contents makes post-mortem fully interpretable later without matching up
71 * the same kernel and hardware config to see what PC values meant.
72 * Dumping its extra ELF program headers includes all the other information
73 * a debugger needs to easily find how the vsyscall DSO was being used.
75 #define ELF_CORE_EXTRA_PHDRS (find_vma(current->mm, VSYSCALL32_BASE) ? \
76 (VSYSCALL32_EHDR->e_phnum) : 0)
77 #define ELF_CORE_WRITE_EXTRA_PHDRS \
79 if (find_vma(current->mm, VSYSCALL32_BASE)) { \
80 const struct elf32_phdr *const vsyscall_phdrs = \
81 (const struct elf32_phdr *) (VSYSCALL32_BASE \
82 + VSYSCALL32_EHDR->e_phoff);\
85 for (i = 0; i < VSYSCALL32_EHDR->e_phnum; ++i) { \
86 struct elf32_phdr phdr = vsyscall_phdrs[i]; \
87 if (phdr.p_type == PT_LOAD) { \
89 ofs = phdr.p_offset = offset; \
90 phdr.p_memsz = PAGE_ALIGN(phdr.p_memsz); \
91 phdr.p_filesz = phdr.p_memsz; \
92 offset += phdr.p_filesz; \
95 phdr.p_offset += ofs; \
96 phdr.p_paddr = 0; /* match other core phdrs */ \
97 DUMP_WRITE(&phdr, sizeof(phdr)); \
101 #define ELF_CORE_WRITE_EXTRA_DATA \
103 if (find_vma(current->mm, VSYSCALL32_BASE)) { \
104 const struct elf32_phdr *const vsyscall_phdrs = \
105 (const struct elf32_phdr *) (VSYSCALL32_BASE \
106 + VSYSCALL32_EHDR->e_phoff); \
108 for (i = 0; i < VSYSCALL32_EHDR->e_phnum; ++i) { \
109 if (vsyscall_phdrs[i].p_type == PT_LOAD) \
110 DUMP_WRITE((void *) (u64) vsyscall_phdrs[i].p_vaddr,\
111 PAGE_ALIGN(vsyscall_phdrs[i].p_memsz)); \
118 int si_signo
; /* signal number */
119 int si_code
; /* extra code */
120 int si_errno
; /* errno */
123 #define jiffies_to_timeval(a,b) do { (b)->tv_usec = 0; (b)->tv_sec = (a)/HZ; }while(0)
127 struct elf_siginfo pr_info
; /* Info associated with signal */
128 short pr_cursig
; /* Current signal */
129 unsigned int pr_sigpend
; /* Set of pending signals */
130 unsigned int pr_sighold
; /* Set of held signals */
135 struct compat_timeval pr_utime
; /* User time */
136 struct compat_timeval pr_stime
; /* System time */
137 struct compat_timeval pr_cutime
; /* Cumulative user time */
138 struct compat_timeval pr_cstime
; /* Cumulative system time */
139 elf_gregset_t pr_reg
; /* GP registers */
140 int pr_fpvalid
; /* True if math co-processor being used. */
143 #define ELF_PRARGSZ (80) /* Number of chars for args */
147 char pr_state
; /* numeric process state */
148 char pr_sname
; /* char for pr_state */
149 char pr_zomb
; /* zombie */
150 char pr_nice
; /* nice val */
151 unsigned int pr_flag
; /* flags */
154 pid_t pr_pid
, pr_ppid
, pr_pgrp
, pr_sid
;
156 char pr_fname
[16]; /* filename of executable */
157 char pr_psargs
[ELF_PRARGSZ
]; /* initial part of arg list */
161 #define STR(x) __STR(x)
163 #define _GET_SEG(x) \
164 ({ __u32 seg; asm("movl %%" STR(x) ",%0" : "=r"(seg)); seg; })
166 /* Assumes current==process to be dumped */
167 #define ELF_CORE_COPY_REGS(pr_reg, regs) \
168 pr_reg[0] = regs->rbx; \
169 pr_reg[1] = regs->rcx; \
170 pr_reg[2] = regs->rdx; \
171 pr_reg[3] = regs->rsi; \
172 pr_reg[4] = regs->rdi; \
173 pr_reg[5] = regs->rbp; \
174 pr_reg[6] = regs->rax; \
175 pr_reg[7] = _GET_SEG(ds); \
176 pr_reg[8] = _GET_SEG(es); \
177 pr_reg[9] = _GET_SEG(fs); \
178 pr_reg[10] = _GET_SEG(gs); \
179 pr_reg[11] = regs->orig_rax; \
180 pr_reg[12] = regs->rip; \
181 pr_reg[13] = regs->cs; \
182 pr_reg[14] = regs->eflags; \
183 pr_reg[15] = regs->rsp; \
184 pr_reg[16] = regs->ss;
188 #define __ASM_X86_64_ELF_H 1
189 #define elf_read_implies_exec(ex, executable_stack) (executable_stack != EXSTACK_DISABLE_X)
190 //#include <asm/ia32.h>
191 #include <linux/elf.h>
193 typedef struct user_i387_ia32_struct elf_fpregset_t
;
194 typedef struct user32_fxsr_struct elf_fpxregset_t
;
197 static inline void elf_core_copy_regs(elf_gregset_t
*elfregs
, struct pt_regs
*regs
)
199 ELF_CORE_COPY_REGS((*elfregs
), regs
)
202 static inline int elf_core_copy_task_regs(struct task_struct
*t
, elf_gregset_t
* elfregs
)
204 struct pt_regs
*pp
= task_pt_regs(t
);
205 ELF_CORE_COPY_REGS((*elfregs
), pp
);
206 /* fix wrong segments */
207 (*elfregs
)[7] = t
->thread
.ds
;
208 (*elfregs
)[9] = t
->thread
.fsindex
;
209 (*elfregs
)[10] = t
->thread
.gsindex
;
210 (*elfregs
)[8] = t
->thread
.es
;
215 elf_core_copy_task_fpregs(struct task_struct
*tsk
, struct pt_regs
*regs
, elf_fpregset_t
*fpu
)
217 struct _fpstate_ia32
*fpstate
= (void*)fpu
;
218 mm_segment_t oldfs
= get_fs();
220 if (!tsk_used_math(tsk
))
223 regs
= task_pt_regs(tsk
);
227 save_i387_ia32(tsk
, fpstate
, regs
, 1);
228 /* Correct for i386 bug. It puts the fop into the upper 16bits of
229 the tag word (like FXSAVE), not into the fcs*/
230 fpstate
->cssel
|= fpstate
->tag
& 0xffff0000;
235 #define ELF_CORE_COPY_XFPREGS 1
237 elf_core_copy_task_xfpregs(struct task_struct
*t
, elf_fpxregset_t
*xfpu
)
239 struct pt_regs
*regs
= task_pt_regs(t
);
240 if (!tsk_used_math(t
))
244 memcpy(xfpu
, &t
->thread
.i387
.fxsave
, sizeof(elf_fpxregset_t
));
245 xfpu
->fcs
= regs
->cs
;
246 xfpu
->fos
= t
->thread
.ds
; /* right? */
250 #undef elf_check_arch
251 #define elf_check_arch(x) \
252 ((x)->e_machine == EM_386)
254 extern int force_personality32
;
256 #define ELF_EXEC_PAGESIZE PAGE_SIZE
257 #define ELF_HWCAP (boot_cpu_data.x86_capability[0])
258 #define ELF_PLATFORM ("i686")
259 #define SET_PERSONALITY(ex, ibcs2) \
261 unsigned long new_flags = 0; \
262 if ((ex).e_ident[EI_CLASS] == ELFCLASS32) \
263 new_flags = _TIF_IA32; \
264 if ((current_thread_info()->flags & _TIF_IA32) \
266 set_thread_flag(TIF_ABI_PENDING); \
268 clear_thread_flag(TIF_ABI_PENDING); \
269 /* XXX This overwrites the user set personality */ \
270 current->personality |= force_personality32; \
273 /* Override some function names */
274 #define elf_format elf32_format
276 #define init_elf_binfmt init_elf32_binfmt
277 #define exit_elf_binfmt exit_elf32_binfmt
279 #define load_elf_binary load_elf32_binary
281 #define ELF_PLAT_INIT(r, load_addr) elf32_init(r)
282 #define setup_arg_pages(bprm, stack_top, exec_stack) \
283 ia32_setup_arg_pages(bprm, stack_top, exec_stack)
284 int ia32_setup_arg_pages(struct linux_binprm
*bprm
, unsigned long stack_top
, int executable_stack
);
287 #define start_thread(regs,new_rip,new_rsp) do { \
288 asm volatile("movl %0,%%fs" :: "r" (0)); \
289 asm volatile("movl %0,%%es; movl %0,%%ds": :"r" (__USER32_DS)); \
291 (regs)->rip = (new_rip); \
292 (regs)->rsp = (new_rsp); \
293 (regs)->eflags = 0x200; \
294 (regs)->cs = __USER32_CS; \
295 (regs)->ss = __USER32_DS; \
300 #include <linux/module.h>
302 MODULE_DESCRIPTION("Binary format loader for compatibility with IA32 ELF binaries.");
303 MODULE_AUTHOR("Eric Youngdale, Andi Kleen");
305 #undef MODULE_DESCRIPTION
308 #define elf_addr_t __u32
310 static void elf32_init(struct pt_regs
*);
312 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
313 #define arch_setup_additional_pages syscall32_setup_pages
314 extern int syscall32_setup_pages(struct linux_binprm
*, int exstack
);
316 #include "../../../fs/binfmt_elf.c"
318 static void elf32_init(struct pt_regs
*regs
)
320 struct task_struct
*me
= current
;
328 regs
->r8
= regs
->r9
= regs
->r10
= regs
->r11
= regs
->r12
=
329 regs
->r13
= regs
->r14
= regs
->r15
= 0;
332 me
->thread
.fsindex
= 0;
333 me
->thread
.gsindex
= 0;
334 me
->thread
.ds
= __USER_DS
;
335 me
->thread
.es
= __USER_DS
;
338 int ia32_setup_arg_pages(struct linux_binprm
*bprm
, unsigned long stack_top
,
339 int executable_stack
)
341 unsigned long stack_base
;
342 struct vm_area_struct
*mpnt
;
343 struct mm_struct
*mm
= current
->mm
;
346 stack_base
= stack_top
- MAX_ARG_PAGES
* PAGE_SIZE
;
347 mm
->arg_start
= bprm
->p
+ stack_base
;
349 bprm
->p
+= stack_base
;
351 bprm
->loader
+= stack_base
;
352 bprm
->exec
+= stack_base
;
354 mpnt
= kmem_cache_alloc(vm_area_cachep
, SLAB_KERNEL
);
358 memset(mpnt
, 0, sizeof(*mpnt
));
360 down_write(&mm
->mmap_sem
);
363 mpnt
->vm_start
= PAGE_MASK
& (unsigned long) bprm
->p
;
364 mpnt
->vm_end
= stack_top
;
365 if (executable_stack
== EXSTACK_ENABLE_X
)
366 mpnt
->vm_flags
= VM_STACK_FLAGS
| VM_EXEC
;
367 else if (executable_stack
== EXSTACK_DISABLE_X
)
368 mpnt
->vm_flags
= VM_STACK_FLAGS
& ~VM_EXEC
;
370 mpnt
->vm_flags
= VM_STACK_FLAGS
;
371 mpnt
->vm_page_prot
= (mpnt
->vm_flags
& VM_EXEC
) ?
372 PAGE_COPY_EXEC
: PAGE_COPY
;
373 if ((ret
= insert_vm_struct(mm
, mpnt
))) {
374 up_write(&mm
->mmap_sem
);
375 kmem_cache_free(vm_area_cachep
, mpnt
);
378 mm
->stack_vm
= mm
->total_vm
= vma_pages(mpnt
);
381 for (i
= 0 ; i
< MAX_ARG_PAGES
; i
++) {
382 struct page
*page
= bprm
->page
[i
];
384 bprm
->page
[i
] = NULL
;
385 install_arg_page(mpnt
, page
, stack_base
);
387 stack_base
+= PAGE_SIZE
;
389 up_write(&mm
->mmap_sem
);
393 EXPORT_SYMBOL(ia32_setup_arg_pages
);
396 /* Register vsyscall32 into the ABI table */
397 #include <linux/sysctl.h>
399 static ctl_table abi_table2
[] = {
400 { 99, "vsyscall32", &sysctl_vsyscall32
, sizeof(int), 0644, NULL
,
405 static ctl_table abi_root_table2
[] = {
406 { .ctl_name
= CTL_ABI
, .procname
= "abi", .mode
= 0555,
407 .child
= abi_table2
},
411 static __init
int ia32_binfmt_init(void)
413 register_sysctl_table(abi_root_table2
, 1);
416 __initcall(ia32_binfmt_init
);