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];
69 int si_signo; /* signal number */
70 int si_code; /* extra code */
71 int si_errno; /* errno */
74 #define jiffies_to_timeval(a,b) do { (b)->tv_usec = 0; (b)->tv_sec = (a)/HZ; }while(0)
78 struct elf_siginfo pr_info; /* Info associated with signal */
79 short pr_cursig; /* Current signal */
80 unsigned int pr_sigpend; /* Set of pending signals */
81 unsigned int pr_sighold; /* Set of held signals */
86 struct compat_timeval pr_utime; /* User time */
87 struct compat_timeval pr_stime; /* System time */
88 struct compat_timeval pr_cutime; /* Cumulative user time */
89 struct compat_timeval pr_cstime; /* Cumulative system time */
90 elf_gregset_t pr_reg; /* GP registers */
91 int pr_fpvalid; /* True if math co-processor being used. */
94 #define ELF_PRARGSZ (80) /* Number of chars for args */
98 char pr_state; /* numeric process state */
99 char pr_sname; /* char for pr_state */
100 char pr_zomb; /* zombie */
101 char pr_nice; /* nice val */
102 unsigned int pr_flag; /* flags */
105 pid_t pr_pid, pr_ppid, pr_pgrp, pr_sid;
107 char pr_fname[16]; /* filename of executable */
108 char pr_psargs[ELF_PRARGSZ]; /* initial part of arg list */
112 #define STR(x) __STR(x)
114 #define _GET_SEG(x) \
115 ({ __u32 seg; asm("movl %%" STR(x) ",%0" : "=r"(seg)); seg; })
117 /* Assumes current==process to be dumped */
118 #define ELF_CORE_COPY_REGS(pr_reg, regs) \
119 pr_reg[0] = regs->rbx; \
120 pr_reg[1] = regs->rcx; \
121 pr_reg[2] = regs->rdx; \
122 pr_reg[3] = regs->rsi; \
123 pr_reg[4] = regs->rdi; \
124 pr_reg[5] = regs->rbp; \
125 pr_reg[6] = regs->rax; \
126 pr_reg[7] = _GET_SEG(ds); \
127 pr_reg[8] = _GET_SEG(es); \
128 pr_reg[9] = _GET_SEG(fs); \
129 pr_reg[10] = _GET_SEG(gs); \
130 pr_reg[11] = regs->orig_rax; \
131 pr_reg[12] = regs->rip; \
132 pr_reg[13] = regs->cs; \
133 pr_reg[14] = regs->eflags; \
134 pr_reg[15] = regs->rsp; \
135 pr_reg[16] = regs->ss;
139 #define __ASM_X86_64_ELF_H 1
140 #define elf_read_implies_exec(ex, executable_stack) (executable_stack != EXSTACK_DISABLE_X)
141 //#include <asm/ia32.h>
142 #include <linux/elf.h>
144 typedef struct user_i387_ia32_struct elf_fpregset_t;
145 typedef struct user32_fxsr_struct elf_fpxregset_t;
148 static inline void elf_core_copy_regs(elf_gregset_t *elfregs, struct pt_regs *regs)
150 ELF_CORE_COPY_REGS((*elfregs), regs)
153 static inline int elf_core_copy_task_regs(struct task_struct *t, elf_gregset_t* elfregs)
155 struct pt_regs *pp = task_pt_regs(t);
156 ELF_CORE_COPY_REGS((*elfregs), pp);
157 /* fix wrong segments */
158 (*elfregs)[7] = t->thread.ds;
159 (*elfregs)[9] = t->thread.fsindex;
160 (*elfregs)[10] = t->thread.gsindex;
161 (*elfregs)[8] = t->thread.es;
166 elf_core_copy_task_fpregs(struct task_struct *tsk, struct pt_regs *regs, elf_fpregset_t *fpu)
168 struct _fpstate_ia32 *fpstate = (void*)fpu;
169 mm_segment_t oldfs = get_fs();
171 if (!tsk_used_math(tsk))
174 regs = task_pt_regs(tsk);
178 save_i387_ia32(tsk, fpstate, regs, 1);
179 /* Correct for i386 bug. It puts the fop into the upper 16bits of
180 the tag word (like FXSAVE), not into the fcs*/
181 fpstate->cssel |= fpstate->tag & 0xffff0000;
186 #define ELF_CORE_COPY_XFPREGS 1
188 elf_core_copy_task_xfpregs(struct task_struct *t, elf_fpxregset_t *xfpu)
190 struct pt_regs *regs = task_pt_regs(t);
191 if (!tsk_used_math(t))
195 memcpy(xfpu, &t->thread.i387.fxsave, sizeof(elf_fpxregset_t));
196 xfpu->fcs = regs->cs;
197 xfpu->fos = t->thread.ds; /* right? */
201 #undef elf_check_arch
202 #define elf_check_arch(x) \
203 ((x)->e_machine == EM_386)
205 extern int force_personality32;
207 #define ELF_EXEC_PAGESIZE PAGE_SIZE
208 #define ELF_HWCAP (boot_cpu_data.x86_capability[0])
209 #define ELF_PLATFORM ("i686")
210 #define SET_PERSONALITY(ex, ibcs2) \
212 unsigned long new_flags = 0; \
213 if ((ex).e_ident[EI_CLASS] == ELFCLASS32) \
214 new_flags = _TIF_IA32; \
215 if ((current_thread_info()->flags & _TIF_IA32) \
217 set_thread_flag(TIF_ABI_PENDING); \
219 clear_thread_flag(TIF_ABI_PENDING); \
220 /* XXX This overwrites the user set personality */ \
221 current->personality |= force_personality32; \
224 /* Override some function names */
225 #define elf_format elf32_format
227 #define init_elf_binfmt init_elf32_binfmt
228 #define exit_elf_binfmt exit_elf32_binfmt
230 #define load_elf_binary load_elf32_binary
232 #define ELF_PLAT_INIT(r, load_addr) elf32_init(r)
233 #define setup_arg_pages(bprm, stack_top, exec_stack) \
234 ia32_setup_arg_pages(bprm, stack_top, exec_stack)
235 int ia32_setup_arg_pages(struct linux_binprm *bprm, unsigned long stack_top, int executable_stack);
238 #define start_thread(regs,new_rip,new_rsp) do { \
239 asm volatile("movl %0,%%fs" :: "r" (0)); \
240 asm volatile("movl %0,%%es; movl %0,%%ds": :"r" (__USER32_DS)); \
242 (regs)->rip = (new_rip); \
243 (regs)->rsp = (new_rsp); \
244 (regs)->eflags = 0x200; \
245 (regs)->cs = __USER32_CS; \
246 (regs)->ss = __USER32_DS; \
251 #include <linux/module.h>
253 MODULE_DESCRIPTION("Binary format loader for compatibility with IA32 ELF binaries.");
254 MODULE_AUTHOR("Eric Youngdale, Andi Kleen");
256 #undef MODULE_DESCRIPTION
259 static void elf32_init(struct pt_regs *);
261 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
262 #define arch_setup_additional_pages syscall32_setup_pages
263 extern int syscall32_setup_pages(struct linux_binprm *, int exstack);
265 #include "../../../fs/binfmt_elf.c"
267 static void elf32_init(struct pt_regs *regs)
269 struct task_struct *me = current;
277 regs->r8 = regs->r9 = regs->r10 = regs->r11 = regs->r12 =
278 regs->r13 = regs->r14 = regs->r15 = 0;
281 me->thread.fsindex = 0;
282 me->thread.gsindex = 0;
283 me->thread.ds = __USER_DS;
284 me->thread.es = __USER_DS;
287 int ia32_setup_arg_pages(struct linux_binprm *bprm, unsigned long stack_top,
288 int executable_stack)
290 unsigned long stack_base;
291 struct vm_area_struct *mpnt;
292 struct mm_struct *mm = current->mm;
295 stack_base = stack_top - MAX_ARG_PAGES * PAGE_SIZE;
296 mm->arg_start = bprm->p + stack_base;
298 bprm->p += stack_base;
300 bprm->loader += stack_base;
301 bprm->exec += stack_base;
303 mpnt = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL);
307 down_write(&mm->mmap_sem);
310 mpnt->vm_start = PAGE_MASK & (unsigned long) bprm->p;
311 mpnt->vm_end = stack_top;
312 if (executable_stack == EXSTACK_ENABLE_X)
313 mpnt->vm_flags = VM_STACK_FLAGS | VM_EXEC;
314 else if (executable_stack == EXSTACK_DISABLE_X)
315 mpnt->vm_flags = VM_STACK_FLAGS & ~VM_EXEC;
317 mpnt->vm_flags = VM_STACK_FLAGS;
318 mpnt->vm_page_prot = (mpnt->vm_flags & VM_EXEC) ?
319 PAGE_COPY_EXEC : PAGE_COPY;
320 if ((ret = insert_vm_struct(mm, mpnt))) {
321 up_write(&mm->mmap_sem);
322 kmem_cache_free(vm_area_cachep, mpnt);
325 mm->stack_vm = mm->total_vm = vma_pages(mpnt);
328 for (i = 0 ; i < MAX_ARG_PAGES ; i++) {
329 struct page *page = bprm->page[i];
331 bprm->page[i] = NULL;
332 install_arg_page(mpnt, page, stack_base);
334 stack_base += PAGE_SIZE;
336 up_write(&mm->mmap_sem);
340 EXPORT_SYMBOL(ia32_setup_arg_pages);
343 /* Register vsyscall32 into the ABI table */
344 #include <linux/sysctl.h>
346 static ctl_table abi_table2[] = {
349 .procname = "vsyscall32",
350 .data = &sysctl_vsyscall32,
351 .maxlen = sizeof(int),
353 .proc_handler = proc_dointvec
358 static ctl_table abi_root_table2[] = {
368 static __init int ia32_binfmt_init(void)
370 register_sysctl_table(abi_root_table2);
373 __initcall(ia32_binfmt_init);