aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86_64/ia32/ia32_binfmt.c
blob: 2fd5a67fd4353d4389a7b68ceab0c85186760c86 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
/* 
 * Written 2000,2002 by Andi Kleen. 
 * 
 * Loosely based on the sparc64 and IA64 32bit emulation loaders.
 * This tricks binfmt_elf.c into loading 32bit binaries using lots 
 * of ugly preprocessor tricks. Talk about very very poor man's inheritance.
 */ 
#include <linux/types.h>
#include <linux/config.h> 
#include <linux/stddef.h>
#include <linux/rwsem.h>
#include <linux/sched.h>
#include <linux/compat.h>
#include <linux/string.h>
#include <linux/binfmts.h>
#include <linux/mm.h>
#include <linux/security.h>

#include <asm/segment.h> 
#include <asm/ptrace.h>
#include <asm/processor.h>
#include <asm/user32.h>
#include <asm/sigcontext32.h>
#include <asm/fpu32.h>
#include <asm/i387.h>
#include <asm/uaccess.h>
#include <asm/ia32.h>
#include <asm/vsyscall32.h>

#define ELF_NAME "elf/i386"

#define AT_SYSINFO 32
#define AT_SYSINFO_EHDR		33

int sysctl_vsyscall32 = 1;

#define ARCH_DLINFO do {  \
	if (sysctl_vsyscall32) { \
	NEW_AUX_ENT(AT_SYSINFO, (u32)(u64)VSYSCALL32_VSYSCALL); \
	NEW_AUX_ENT(AT_SYSINFO_EHDR, VSYSCALL32_BASE);    \
	}	\
} while(0)

struct file;
struct elf_phdr; 

#define IA32_EMULATOR 1

#define ELF_ET_DYN_BASE		(TASK_UNMAPPED_BASE + 0x1000000)

#undef ELF_ARCH
#define ELF_ARCH EM_386

#undef ELF_CLASS
#define ELF_CLASS ELFCLASS32

#define ELF_DATA	ELFDATA2LSB

#define USE_ELF_CORE_DUMP 1

/* Override elfcore.h */ 
#define _LINUX_ELFCORE_H 1
typedef unsigned int elf_greg_t;

#define ELF_NGREG (sizeof (struct user_regs_struct32) / sizeof(elf_greg_t))
typedef elf_greg_t elf_gregset_t[ELF_NGREG];

/*
 * These macros parameterize elf_core_dump in fs/binfmt_elf.c to write out
 * extra segments containing the vsyscall DSO contents.  Dumping its
 * contents makes post-mortem fully interpretable later without matching up
 * the same kernel and hardware config to see what PC values meant.
 * Dumping its extra ELF program headers includes all the other information
 * a debugger needs to easily find how the vsyscall DSO was being used.
 */
#define ELF_CORE_EXTRA_PHDRS	(find_vma(current->mm, VSYSCALL32_BASE) ?     \
    (VSYSCALL32_EHDR->e_phnum) : 0)
#define ELF_CORE_WRITE_EXTRA_PHDRS					      \
do {									      \
	if (find_vma(current->mm, VSYSCALL32_BASE)) { 			      \
		const struct elf32_phdr *const vsyscall_phdrs =		      \
			(const struct elf32_phdr *) (VSYSCALL32_BASE	      \
						   + VSYSCALL32_EHDR->e_phoff);\
		int i;							      \
		Elf32_Off ofs = 0;					      \
		for (i = 0; i < VSYSCALL32_EHDR->e_phnum; ++i) {	      \
			struct elf32_phdr phdr = vsyscall_phdrs[i];	      \
			if (phdr.p_type == PT_LOAD) {			      \
				BUG_ON(ofs != 0);			      \
				ofs = phdr.p_offset = offset;		      \
				phdr.p_memsz = PAGE_ALIGN(phdr.p_memsz);      \
				phdr.p_filesz = phdr.p_memsz;		      \
				offset += phdr.p_filesz;		      \
			}						      \
			else						      \
				phdr.p_offset += ofs;			      \
			phdr.p_paddr = 0; /* match other core phdrs */	      \
			DUMP_WRITE(&phdr, sizeof(phdr));		      \
		}							      \
	}								      \
} while (0)
#define ELF_CORE_WRITE_EXTRA_DATA					      \
do {									      \
	if (find_vma(current->mm, VSYSCALL32_BASE)) { 			      \
		const struct elf32_phdr *const vsyscall_phdrs =		      \
			(const struct elf32_phdr *) (VSYSCALL32_BASE	      \
						   + VSYSCALL32_EHDR->e_phoff);      \
		int i;							      \
		for (i = 0; i < VSYSCALL32_EHDR->e_phnum; ++i) {	      \
			if (vsyscall_phdrs[i].p_type == PT_LOAD)	      \
				DUMP_WRITE((void *) (u64) vsyscall_phdrs[i].p_vaddr,\
				    PAGE_ALIGN(vsyscall_phdrs[i].p_memsz));   \
		}							      \
	}								      \
} while (0)

struct elf_siginfo
{
	int	si_signo;			/* signal number */
	int	si_code;			/* extra code */
	int	si_errno;			/* errno */
};

#define jiffies_to_timeval(a,b) do { (b)->tv_usec = 0; (b)->tv_sec = (a)/HZ; }while(0)

struct elf_prstatus
{
	struct elf_siginfo pr_info;	/* Info associated with signal */
	short	pr_cursig;		/* Current signal */
	unsigned int pr_sigpend;	/* Set of pending signals */
	unsigned int pr_sighold;	/* Set of held signals */
	pid_t	pr_pid;
	pid_t	pr_ppid;
	pid_t	pr_pgrp;
	pid_t	pr_sid;
	struct compat_timeval pr_utime;	/* User time */
	struct compat_timeval pr_stime;	/* System time */
	struct compat_timeval pr_cutime;	/* Cumulative user time */
	struct compat_timeval pr_cstime;	/* Cumulative system time */
	elf_gregset_t pr_reg;	/* GP registers */
	int pr_fpvalid;		/* True if math co-processor being used.  */
};

#define ELF_PRARGSZ	(80)	/* Number of chars for args */

struct elf_prpsinfo
{
	char	pr_state;	/* numeric process state */
	char	pr_sname;	/* char for pr_state */
	char	pr_zomb;	/* zombie */
	char	pr_nice;	/* nice val */
	unsigned int pr_flag;	/* flags */
	__u16	pr_uid;
	__u16	pr_gid;
	pid_t	pr_pid, pr_ppid, pr_pgrp, pr_sid;
	/* Lots missing */
	char	pr_fname[16];	/* filename of executable */
	char	pr_psargs[ELF_PRARGSZ];	/* initial part of arg list */
};

#define __STR(x) #x
#define STR(x) __STR(x)

#define _GET_SEG(x) \
	({ __u32 seg; asm("movl %%" STR(x) ",%0" : "=r"(seg)); seg; })

/* Assumes current==process to be dumped */
#define ELF_CORE_COPY_REGS(pr_reg, regs)       		\
	pr_reg[0] = regs->rbx;				\
	pr_reg[1] = regs->rcx;				\
	pr_reg[2] = regs->rdx;				\
	pr_reg[3] = regs->rsi;				\
	pr_reg[4] = regs->rdi;				\
	pr_reg[5] = regs->rbp;				\
	pr_reg[6] = regs->rax;				\
	pr_reg[7] = _GET_SEG(ds);   			\
	pr_reg[8] = _GET_SEG(es);			\
	pr_reg[9] = _GET_SEG(fs);			\
	pr_reg[10] = _GET_SEG(gs);			\
	pr_reg[11] = regs->orig_rax;			\
	pr_reg[12] = regs->rip;				\
	pr_reg[13] = regs->cs;				\
	pr_reg[14] = regs->eflags;			\
	pr_reg[15] = regs->rsp;				\
	pr_reg[16] = regs->ss;

#define user user32

#define __ASM_X86_64_ELF_H 1
#define elf_read_implies_exec(ex, executable_stack)     (executable_stack != EXSTACK_DISABLE_X)
//#include <asm/ia32.h>
#include <linux/elf.h>

typedef struct user_i387_ia32_struct elf_fpregset_t;
typedef struct user32_fxsr_struct elf_fpxregset_t;


static inline void elf_core_copy_regs(elf_gregset_t *elfregs, struct pt_regs *regs)
{
	ELF_CORE_COPY_REGS((*elfregs), regs)
}

static inline int elf_core_copy_task_regs(struct task_struct *t, elf_gregset_t* elfregs)
{	
	struct pt_regs *pp = task_pt_regs(t);
	ELF_CORE_COPY_REGS((*elfregs), pp);
	/* fix wrong segments */ 
	(*elfregs)[7] = t->thread.ds; 
	(*elfregs)[9] = t->thread.fsindex; 
	(*elfregs)[10] = t->thread.gsindex; 
	(*elfregs)[8] = t->thread.es; 	
	return 1; 
}

static inline int 
elf_core_copy_task_fpregs(struct task_struct *tsk, struct pt_regs *regs, elf_fpregset_t *fpu)
{
	struct _fpstate_ia32 *fpstate = (void*)fpu; 
	mm_segment_t oldfs = get_fs();

	if (!tsk_used_math(tsk))
		return 0;
	if (!regs)
		regs = task_pt_regs(tsk);
	if (tsk == current)
		unlazy_fpu(tsk);
	set_fs(KERNEL_DS); 
	save_i387_ia32(tsk, fpstate, regs, 1);
	/* Correct for i386 bug. It puts the fop into the upper 16bits of 
	   the tag word (like FXSAVE), not into the fcs*/ 
	fpstate->cssel |= fpstate->tag & 0xffff0000; 
	set_fs(oldfs); 
	return 1; 
}

#define ELF_CORE_COPY_XFPREGS 1
static inline int 
elf_core_copy_task_xfpregs(struct task_struct *t, elf_fpxregset_t *xfpu)
{
	struct pt_regs *regs = task_pt_regs(t);
	if (!tsk_used_math(t))
		return 0;
	if (t == current)
		unlazy_fpu(t); 
	memcpy(xfpu, &t->thread.i387.fxsave, sizeof(elf_fpxregset_t));
	xfpu->fcs = regs->cs; 
	xfpu->fos = t->thread.ds; /* right? */ 
	return 1;
}

#undef elf_check_arch
#define elf_check_arch(x) \
	((x)->e_machine == EM_386)

extern int force_personality32;

#define ELF_EXEC_PAGESIZE PAGE_SIZE
#define ELF_HWCAP (boot_cpu_data.x86_capability[0])
#define ELF_PLATFORM  ("i686")
#define SET_PERSONALITY(ex, ibcs2)			\
do {							\
	unsigned long new_flags = 0;				\
	if ((ex).e_ident[EI_CLASS] == ELFCLASS32)		\
		new_flags = _TIF_IA32;				\
	if ((current_thread_info()->flags & _TIF_IA32)		\
	    != new_flags)					\
		set_thread_flag(TIF_ABI_PENDING);		\
	else							\
		clear_thread_flag(TIF_ABI_PENDING);		\
	/* XXX This overwrites the user set personality */	\
	current->personality |= force_personality32;		\
} while (0)

/* Override some function names */
#define elf_format			elf32_format

#define init_elf_binfmt			init_elf32_binfmt
#define exit_elf_binfmt			exit_elf32_binfmt

#define load_elf_binary load_elf32_binary

#define ELF_PLAT_INIT(r, load_addr)	elf32_init(r)
#define setup_arg_pages(bprm, stack_top, exec_stack) \
	ia32_setup_arg_pages(bprm, stack_top, exec_stack)
int ia32_setup_arg_pages(struct linux_binprm *bprm, unsigned long stack_top, int executable_stack);

#undef start_thread
#define start_thread(regs,new_rip,new_rsp) do { \
	asm volatile("movl %0,%%fs" :: "r" (0)); \
	asm volatile("movl %0,%%es; movl %0,%%ds": :"r" (__USER32_DS)); \
	load_gs_index(0); \
	(regs)->rip = (new_rip); \
	(regs)->rsp = (new_rsp); \
	(regs)->eflags = 0x200; \
	(regs)->cs = __USER32_CS; \
	(regs)->ss = __USER32_DS; \
	set_fs(USER_DS); \
} while(0) 


#include <linux/module.h>

MODULE_DESCRIPTION("Binary format loader for compatibility with IA32 ELF binaries."); 
MODULE_AUTHOR("Eric Youngdale, Andi Kleen");

#undef MODULE_DESCRIPTION
#undef MODULE_AUTHOR

#define elf_addr_t __u32

static void elf32_init(struct pt_regs *);

#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
#define arch_setup_additional_pages syscall32_setup_pages
extern int syscall32_setup_pages(struct linux_binprm *, int exstack);

#include "../../../fs/binfmt_elf.c" 

static void elf32_init(struct pt_regs *regs)
{
	struct task_struct *me = current; 
	regs->rdi = 0;
	regs->rsi = 0;
	regs->rdx = 0;
	regs->rcx = 0;
	regs->rax = 0;
	regs->rbx = 0; 
	regs->rbp = 0; 
	regs->r8 = regs->r9 = regs->r10 = regs->r11 = regs->r12 =
		regs->r13 = regs->r14 = regs->r15 = 0; 
    me->thread.fs = 0; 
	me->thread.gs = 0;
	me->thread.fsindex = 0; 
	me->thread.gsindex = 0;
    me->thread.ds = __USER_DS; 
	me->thread.es = __USER_DS;
}

int ia32_setup_arg_pages(struct linux_binprm *bprm, unsigned long stack_top,
			 int executable_stack)
{
	unsigned long stack_base;
	struct vm_area_struct *mpnt;
	struct mm_struct *mm = current->mm;
	int i, ret;

	stack_base = stack_top - MAX_ARG_PAGES * PAGE_SIZE;
	mm->arg_start = bprm->p + stack_base;

	bprm->p += stack_base;
	if (bprm->loader)
		bprm->loader += stack_base;
	bprm->exec += stack_base;

	mpnt = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
	if (!mpnt) 
		return -ENOMEM; 

	memset(mpnt, 0, sizeof(*mpnt));

	down_write(&mm->mmap_sem);
	{
		mpnt->vm_mm = mm;
		mpnt->vm_start = PAGE_MASK & (unsigned long) bprm->p;
		mpnt->vm_end = stack_top;
		if (executable_stack == EXSTACK_ENABLE_X)
			mpnt->vm_flags = VM_STACK_FLAGS |  VM_EXEC;
		else if (executable_stack == EXSTACK_DISABLE_X)
			mpnt->vm_flags = VM_STACK_FLAGS & ~VM_EXEC;
		else
			mpnt->vm_flags = VM_STACK_FLAGS;
 		mpnt->vm_page_prot = (mpnt->vm_flags & VM_EXEC) ? 
 			PAGE_COPY_EXEC : PAGE_COPY;
		if ((ret = insert_vm_struct(mm, mpnt))) {
			up_write(&mm->mmap_sem);
			kmem_cache_free(vm_area_cachep, mpnt);
			return ret;
		}
		mm->stack_vm = mm->total_vm = vma_pages(mpnt);
	} 

	for (i = 0 ; i < MAX_ARG_PAGES ; i++) {
		struct page *page = bprm->page[i];
		if (page) {
			bprm->page[i] = NULL;
			install_arg_page(mpnt, page, stack_base);
		}
		stack_base += PAGE_SIZE;
	}
	up_write(&mm->mmap_sem);
	
	return 0;
}
EXPORT_SYMBOL(ia32_setup_arg_pages);

#ifdef CONFIG_SYSCTL
/* Register vsyscall32 into the ABI table */
#include <linux/sysctl.h>

static ctl_table abi_table2[] = {
	{ 99, "vsyscall32", &sysctl_vsyscall32, sizeof(int), 0644, NULL,
	  proc_dointvec },
	{ 0, }
}; 

static ctl_table abi_root_table2[] = { 
	{ .ctl_name = CTL_ABI, .procname = "abi", .mode = 0555, 
	  .child = abi_table2 }, 
	{ 0 }, 
}; 

static __init int ia32_binfmt_init(void)
{ 
	register_sysctl_table(abi_root_table2, 1);
	return 0;
}
__initcall(ia32_binfmt_init);
#endif