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/config.h>
10 #include <linux/stddef.h>
11 #include <linux/rwsem.h>
12 #include <linux/sched.h>
13 #include <linux/compat.h>
14 #include <linux/string.h>
15 #include <linux/binfmts.h>
17 #include <linux/security.h>
19 #include <asm/segment.h>
20 #include <asm/ptrace.h>
21 #include <asm/processor.h>
22 #include <asm/user32.h>
23 #include <asm/sigcontext32.h>
24 #include <asm/fpu32.h>
26 #include <asm/uaccess.h>
28 #include <asm/vsyscall32.h>
30 #define ELF_NAME "elf/i386"
33 #define AT_SYSINFO_EHDR 33
35 int sysctl_vsyscall32
= 1;
37 #define ARCH_DLINFO do { \
38 if (sysctl_vsyscall32) { \
39 NEW_AUX_ENT(AT_SYSINFO, (u32)(u64)VSYSCALL32_VSYSCALL); \
40 NEW_AUX_ENT(AT_SYSINFO_EHDR, VSYSCALL32_BASE); \
47 #define IA32_EMULATOR 1
49 #define ELF_ET_DYN_BASE (TASK_UNMAPPED_BASE + 0x1000000)
52 #define ELF_ARCH EM_386
55 #define ELF_CLASS ELFCLASS32
57 #define ELF_DATA ELFDATA2LSB
59 #define USE_ELF_CORE_DUMP 1
61 /* Overwrite elfcore.h */
62 #define _LINUX_ELFCORE_H 1
63 typedef unsigned int elf_greg_t
;
65 #define ELF_NGREG (sizeof (struct user_regs_struct32) / sizeof(elf_greg_t))
66 typedef elf_greg_t elf_gregset_t
[ELF_NGREG
];
69 * These macros parameterize elf_core_dump in fs/binfmt_elf.c to write out
70 * extra segments containing the vsyscall DSO contents. Dumping its
71 * contents makes post-mortem fully interpretable later without matching up
72 * the same kernel and hardware config to see what PC values meant.
73 * Dumping its extra ELF program headers includes all the other information
74 * a debugger needs to easily find how the vsyscall DSO was being used.
76 #define ELF_CORE_EXTRA_PHDRS (VSYSCALL32_EHDR->e_phnum)
77 #define ELF_CORE_WRITE_EXTRA_PHDRS \
79 const struct elf32_phdr *const vsyscall_phdrs = \
80 (const struct elf32_phdr *) (VSYSCALL32_BASE \
81 + VSYSCALL32_EHDR->e_phoff); \
84 for (i = 0; i < VSYSCALL32_EHDR->e_phnum; ++i) { \
85 struct elf32_phdr phdr = vsyscall_phdrs[i]; \
86 if (phdr.p_type == PT_LOAD) { \
88 ofs = phdr.p_offset = offset; \
89 phdr.p_memsz = PAGE_ALIGN(phdr.p_memsz); \
90 phdr.p_filesz = phdr.p_memsz; \
91 offset += phdr.p_filesz; \
94 phdr.p_offset += ofs; \
95 phdr.p_paddr = 0; /* match other core phdrs */ \
96 DUMP_WRITE(&phdr, sizeof(phdr)); \
99 #define ELF_CORE_WRITE_EXTRA_DATA \
101 const struct elf32_phdr *const vsyscall_phdrs = \
102 (const struct elf32_phdr *) (VSYSCALL32_BASE \
103 + VSYSCALL32_EHDR->e_phoff); \
105 for (i = 0; i < VSYSCALL32_EHDR->e_phnum; ++i) { \
106 if (vsyscall_phdrs[i].p_type == PT_LOAD) \
107 DUMP_WRITE((void *) (u64) vsyscall_phdrs[i].p_vaddr, \
108 PAGE_ALIGN(vsyscall_phdrs[i].p_memsz)); \
114 int si_signo
; /* signal number */
115 int si_code
; /* extra code */
116 int si_errno
; /* errno */
119 #define jiffies_to_timeval(a,b) do { (b)->tv_usec = 0; (b)->tv_sec = (a)/HZ; }while(0)
123 struct elf_siginfo pr_info
; /* Info associated with signal */
124 short pr_cursig
; /* Current signal */
125 unsigned int pr_sigpend
; /* Set of pending signals */
126 unsigned int pr_sighold
; /* Set of held signals */
131 struct compat_timeval pr_utime
; /* User time */
132 struct compat_timeval pr_stime
; /* System time */
133 struct compat_timeval pr_cutime
; /* Cumulative user time */
134 struct compat_timeval pr_cstime
; /* Cumulative system time */
135 elf_gregset_t pr_reg
; /* GP registers */
136 int pr_fpvalid
; /* True if math co-processor being used. */
139 #define ELF_PRARGSZ (80) /* Number of chars for args */
143 char pr_state
; /* numeric process state */
144 char pr_sname
; /* char for pr_state */
145 char pr_zomb
; /* zombie */
146 char pr_nice
; /* nice val */
147 unsigned int pr_flag
; /* flags */
150 pid_t pr_pid
, pr_ppid
, pr_pgrp
, pr_sid
;
152 char pr_fname
[16]; /* filename of executable */
153 char pr_psargs
[ELF_PRARGSZ
]; /* initial part of arg list */
157 #define STR(x) __STR(x)
159 #define _GET_SEG(x) \
160 ({ __u32 seg; asm("movl %%" STR(x) ",%0" : "=r"(seg)); seg; })
162 /* Assumes current==process to be dumped */
163 #define ELF_CORE_COPY_REGS(pr_reg, regs) \
164 pr_reg[0] = regs->rbx; \
165 pr_reg[1] = regs->rcx; \
166 pr_reg[2] = regs->rdx; \
167 pr_reg[3] = regs->rsi; \
168 pr_reg[4] = regs->rdi; \
169 pr_reg[5] = regs->rbp; \
170 pr_reg[6] = regs->rax; \
171 pr_reg[7] = _GET_SEG(ds); \
172 pr_reg[8] = _GET_SEG(es); \
173 pr_reg[9] = _GET_SEG(fs); \
174 pr_reg[10] = _GET_SEG(gs); \
175 pr_reg[11] = regs->orig_rax; \
176 pr_reg[12] = regs->rip; \
177 pr_reg[13] = regs->cs; \
178 pr_reg[14] = regs->eflags; \
179 pr_reg[15] = regs->rsp; \
180 pr_reg[16] = regs->ss;
184 #define __ASM_X86_64_ELF_H 1
185 #define elf_read_implies_exec(ex, have_pt_gnu_stack) (!(have_pt_gnu_stack))
186 //#include <asm/ia32.h>
187 #include <linux/elf.h>
189 typedef struct user_i387_ia32_struct elf_fpregset_t
;
190 typedef struct user32_fxsr_struct elf_fpxregset_t
;
193 static inline void elf_core_copy_regs(elf_gregset_t
*elfregs
, struct pt_regs
*regs
)
195 ELF_CORE_COPY_REGS((*elfregs
), regs
)
198 static inline int elf_core_copy_task_regs(struct task_struct
*t
, elf_gregset_t
* elfregs
)
200 struct pt_regs
*pp
= (struct pt_regs
*)(t
->thread
.rsp0
);
202 ELF_CORE_COPY_REGS((*elfregs
), pp
);
203 /* fix wrong segments */
204 (*elfregs
)[7] = t
->thread
.ds
;
205 (*elfregs
)[9] = t
->thread
.fsindex
;
206 (*elfregs
)[10] = t
->thread
.gsindex
;
207 (*elfregs
)[8] = t
->thread
.es
;
212 elf_core_copy_task_fpregs(struct task_struct
*tsk
, struct pt_regs
*regs
, elf_fpregset_t
*fpu
)
214 struct _fpstate_ia32
*fpstate
= (void*)fpu
;
215 mm_segment_t oldfs
= get_fs();
217 if (!tsk_used_math(tsk
))
220 regs
= ((struct pt_regs
*)tsk
->thread
.rsp0
) - 1;
224 save_i387_ia32(tsk
, fpstate
, regs
, 1);
225 /* Correct for i386 bug. It puts the fop into the upper 16bits of
226 the tag word (like FXSAVE), not into the fcs*/
227 fpstate
->cssel
|= fpstate
->tag
& 0xffff0000;
232 #define ELF_CORE_COPY_XFPREGS 1
234 elf_core_copy_task_xfpregs(struct task_struct
*t
, elf_fpxregset_t
*xfpu
)
236 struct pt_regs
*regs
= ((struct pt_regs
*)(t
->thread
.rsp0
))-1;
237 if (!tsk_used_math(t
))
241 memcpy(xfpu
, &t
->thread
.i387
.fxsave
, sizeof(elf_fpxregset_t
));
242 xfpu
->fcs
= regs
->cs
;
243 xfpu
->fos
= t
->thread
.ds
; /* right? */
247 #undef elf_check_arch
248 #define elf_check_arch(x) \
249 ((x)->e_machine == EM_386)
251 extern int force_personality32
;
253 #define ELF_EXEC_PAGESIZE PAGE_SIZE
254 #define ELF_HWCAP (boot_cpu_data.x86_capability[0])
255 #define ELF_PLATFORM ("i686")
256 #define SET_PERSONALITY(ex, ibcs2) \
258 unsigned long new_flags = 0; \
259 if ((ex).e_ident[EI_CLASS] == ELFCLASS32) \
260 new_flags = _TIF_IA32; \
261 if ((current_thread_info()->flags & _TIF_IA32) \
263 set_thread_flag(TIF_ABI_PENDING); \
265 clear_thread_flag(TIF_ABI_PENDING); \
266 /* XXX This overwrites the user set personality */ \
267 current->personality |= force_personality32; \
270 /* Override some function names */
271 #define elf_format elf32_format
273 #define init_elf_binfmt init_elf32_binfmt
274 #define exit_elf_binfmt exit_elf32_binfmt
276 #define load_elf_binary load_elf32_binary
278 #define ELF_PLAT_INIT(r, load_addr) elf32_init(r)
279 #define setup_arg_pages(bprm, stack_top, exec_stack) \
280 ia32_setup_arg_pages(bprm, stack_top, exec_stack)
281 int ia32_setup_arg_pages(struct linux_binprm
*bprm
, unsigned long stack_top
, int executable_stack
);
284 #define start_thread(regs,new_rip,new_rsp) do { \
285 asm volatile("movl %0,%%fs" :: "r" (0)); \
286 asm volatile("movl %0,%%es; movl %0,%%ds": :"r" (__USER32_DS)); \
288 (regs)->rip = (new_rip); \
289 (regs)->rsp = (new_rsp); \
290 (regs)->eflags = 0x200; \
291 (regs)->cs = __USER32_CS; \
292 (regs)->ss = __USER32_DS; \
297 #define elf_map elf32_map
299 #include <linux/module.h>
301 MODULE_DESCRIPTION("Binary format loader for compatibility with IA32 ELF binaries.");
302 MODULE_AUTHOR("Eric Youngdale, Andi Kleen");
304 #undef MODULE_DESCRIPTION
307 #define elf_addr_t __u32
309 static void elf32_init(struct pt_regs
*);
311 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
312 #define arch_setup_additional_pages syscall32_setup_pages
313 extern int syscall32_setup_pages(struct linux_binprm
*, int exstack
);
315 #include "../../../fs/binfmt_elf.c"
317 static void elf32_init(struct pt_regs
*regs
)
319 struct task_struct
*me
= current
;
327 regs
->r8
= regs
->r9
= regs
->r10
= regs
->r11
= regs
->r12
=
328 regs
->r13
= regs
->r14
= regs
->r15
= 0;
331 me
->thread
.fsindex
= 0;
332 me
->thread
.gsindex
= 0;
333 me
->thread
.ds
= __USER_DS
;
334 me
->thread
.es
= __USER_DS
;
337 int ia32_setup_arg_pages(struct linux_binprm
*bprm
, unsigned long stack_top
,
338 int executable_stack
)
340 unsigned long stack_base
;
341 struct vm_area_struct
*mpnt
;
342 struct mm_struct
*mm
= current
->mm
;
345 stack_base
= IA32_STACK_TOP
- MAX_ARG_PAGES
* PAGE_SIZE
;
346 mm
->arg_start
= bprm
->p
+ stack_base
;
348 bprm
->p
+= stack_base
;
350 bprm
->loader
+= stack_base
;
351 bprm
->exec
+= stack_base
;
353 mpnt
= kmem_cache_alloc(vm_area_cachep
, SLAB_KERNEL
);
357 memset(mpnt
, 0, sizeof(*mpnt
));
359 down_write(&mm
->mmap_sem
);
362 mpnt
->vm_start
= PAGE_MASK
& (unsigned long) bprm
->p
;
363 mpnt
->vm_end
= IA32_STACK_TOP
;
364 if (executable_stack
== EXSTACK_ENABLE_X
)
365 mpnt
->vm_flags
= VM_STACK_FLAGS
| VM_EXEC
;
366 else if (executable_stack
== EXSTACK_DISABLE_X
)
367 mpnt
->vm_flags
= VM_STACK_FLAGS
& ~VM_EXEC
;
369 mpnt
->vm_flags
= VM_STACK_FLAGS
;
370 mpnt
->vm_page_prot
= (mpnt
->vm_flags
& VM_EXEC
) ?
371 PAGE_COPY_EXEC
: PAGE_COPY
;
372 if ((ret
= insert_vm_struct(mm
, mpnt
))) {
373 up_write(&mm
->mmap_sem
);
374 kmem_cache_free(vm_area_cachep
, mpnt
);
377 mm
->stack_vm
= mm
->total_vm
= vma_pages(mpnt
);
380 for (i
= 0 ; i
< MAX_ARG_PAGES
; i
++) {
381 struct page
*page
= bprm
->page
[i
];
383 bprm
->page
[i
] = NULL
;
384 install_arg_page(mpnt
, page
, stack_base
);
386 stack_base
+= PAGE_SIZE
;
388 up_write(&mm
->mmap_sem
);
392 EXPORT_SYMBOL(ia32_setup_arg_pages
);
395 elf32_map (struct file
*filep
, unsigned long addr
, struct elf_phdr
*eppnt
, int prot
, int type
)
397 unsigned long map_addr
;
398 struct task_struct
*me
= current
;
400 down_write(&me
->mm
->mmap_sem
);
401 map_addr
= do_mmap(filep
, ELF_PAGESTART(addr
),
402 eppnt
->p_filesz
+ ELF_PAGEOFFSET(eppnt
->p_vaddr
), prot
,
404 eppnt
->p_offset
- ELF_PAGEOFFSET(eppnt
->p_vaddr
));
405 up_write(&me
->mm
->mmap_sem
);
410 /* Register vsyscall32 into the ABI table */
411 #include <linux/sysctl.h>
413 static ctl_table abi_table2
[] = {
414 { 99, "vsyscall32", &sysctl_vsyscall32
, sizeof(int), 0644, NULL
,
419 static ctl_table abi_root_table2
[] = {
420 { .ctl_name
= CTL_ABI
, .procname
= "abi", .mode
= 0555,
421 .child
= abi_table2
},
425 static __init
int ia32_binfmt_init(void)
427 register_sysctl_table(abi_root_table2
, 1);
430 __initcall(ia32_binfmt_init
);