mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
327 lines
8.0 KiB
327 lines
8.0 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
|
* a.out loader for x86-64 |
|
* |
|
* Copyright (C) 1991, 1992, 1996 Linus Torvalds |
|
* Hacked together by Andi Kleen |
|
*/ |
|
|
|
#include <linux/module.h> |
|
|
|
#include <linux/time.h> |
|
#include <linux/kernel.h> |
|
#include <linux/mm.h> |
|
#include <linux/mman.h> |
|
#include <linux/a.out.h> |
|
#include <linux/errno.h> |
|
#include <linux/signal.h> |
|
#include <linux/string.h> |
|
#include <linux/fs.h> |
|
#include <linux/file.h> |
|
#include <linux/stat.h> |
|
#include <linux/fcntl.h> |
|
#include <linux/ptrace.h> |
|
#include <linux/user.h> |
|
#include <linux/binfmts.h> |
|
#include <linux/personality.h> |
|
#include <linux/init.h> |
|
#include <linux/jiffies.h> |
|
#include <linux/perf_event.h> |
|
#include <linux/sched/task_stack.h> |
|
|
|
#include <linux/uaccess.h> |
|
#include <asm/cacheflush.h> |
|
#include <asm/user32.h> |
|
#include <asm/ia32.h> |
|
|
|
#undef WARN_OLD |
|
|
|
static int load_aout_binary(struct linux_binprm *); |
|
static int load_aout_library(struct file *); |
|
|
|
static struct linux_binfmt aout_format = { |
|
.module = THIS_MODULE, |
|
.load_binary = load_aout_binary, |
|
.load_shlib = load_aout_library, |
|
}; |
|
|
|
static int set_brk(unsigned long start, unsigned long end) |
|
{ |
|
start = PAGE_ALIGN(start); |
|
end = PAGE_ALIGN(end); |
|
if (end <= start) |
|
return 0; |
|
return vm_brk(start, end - start); |
|
} |
|
|
|
|
|
/* |
|
* create_aout_tables() parses the env- and arg-strings in new user |
|
* memory and creates the pointer tables from them, and puts their |
|
* addresses on the "stack", returning the new stack pointer value. |
|
*/ |
|
static u32 __user *create_aout_tables(char __user *p, struct linux_binprm *bprm) |
|
{ |
|
u32 __user *argv, *envp, *sp; |
|
int argc = bprm->argc, envc = bprm->envc; |
|
|
|
sp = (u32 __user *) ((-(unsigned long)sizeof(u32)) & (unsigned long) p); |
|
sp -= envc+1; |
|
envp = sp; |
|
sp -= argc+1; |
|
argv = sp; |
|
put_user((unsigned long) envp, --sp); |
|
put_user((unsigned long) argv, --sp); |
|
put_user(argc, --sp); |
|
current->mm->arg_start = (unsigned long) p; |
|
while (argc-- > 0) { |
|
char c; |
|
|
|
put_user((u32)(unsigned long)p, argv++); |
|
do { |
|
get_user(c, p++); |
|
} while (c); |
|
} |
|
put_user(0, argv); |
|
current->mm->arg_end = current->mm->env_start = (unsigned long) p; |
|
while (envc-- > 0) { |
|
char c; |
|
|
|
put_user((u32)(unsigned long)p, envp++); |
|
do { |
|
get_user(c, p++); |
|
} while (c); |
|
} |
|
put_user(0, envp); |
|
current->mm->env_end = (unsigned long) p; |
|
return sp; |
|
} |
|
|
|
/* |
|
* These are the functions used to load a.out style executables and shared |
|
* libraries. There is no binary dependent code anywhere else. |
|
*/ |
|
static int load_aout_binary(struct linux_binprm *bprm) |
|
{ |
|
unsigned long error, fd_offset, rlim; |
|
struct pt_regs *regs = current_pt_regs(); |
|
struct exec ex; |
|
int retval; |
|
|
|
ex = *((struct exec *) bprm->buf); /* exec-header */ |
|
if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != OMAGIC && |
|
N_MAGIC(ex) != QMAGIC && N_MAGIC(ex) != NMAGIC) || |
|
N_TRSIZE(ex) || N_DRSIZE(ex) || |
|
i_size_read(file_inode(bprm->file)) < |
|
ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) { |
|
return -ENOEXEC; |
|
} |
|
|
|
fd_offset = N_TXTOFF(ex); |
|
|
|
/* Check initial limits. This avoids letting people circumvent |
|
* size limits imposed on them by creating programs with large |
|
* arrays in the data or bss. |
|
*/ |
|
rlim = rlimit(RLIMIT_DATA); |
|
if (rlim >= RLIM_INFINITY) |
|
rlim = ~0; |
|
if (ex.a_data + ex.a_bss > rlim) |
|
return -ENOMEM; |
|
|
|
/* Flush all traces of the currently running executable */ |
|
retval = begin_new_exec(bprm); |
|
if (retval) |
|
return retval; |
|
|
|
/* OK, This is the point of no return */ |
|
set_personality(PER_LINUX); |
|
set_personality_ia32(false); |
|
|
|
setup_new_exec(bprm); |
|
|
|
regs->cs = __USER32_CS; |
|
regs->r8 = regs->r9 = regs->r10 = regs->r11 = regs->r12 = |
|
regs->r13 = regs->r14 = regs->r15 = 0; |
|
|
|
current->mm->end_code = ex.a_text + |
|
(current->mm->start_code = N_TXTADDR(ex)); |
|
current->mm->end_data = ex.a_data + |
|
(current->mm->start_data = N_DATADDR(ex)); |
|
current->mm->brk = ex.a_bss + |
|
(current->mm->start_brk = N_BSSADDR(ex)); |
|
|
|
retval = setup_arg_pages(bprm, IA32_STACK_TOP, EXSTACK_DEFAULT); |
|
if (retval < 0) |
|
return retval; |
|
|
|
if (N_MAGIC(ex) == OMAGIC) { |
|
unsigned long text_addr, map_size; |
|
|
|
text_addr = N_TXTADDR(ex); |
|
map_size = ex.a_text+ex.a_data; |
|
|
|
error = vm_brk(text_addr & PAGE_MASK, map_size); |
|
|
|
if (error) |
|
return error; |
|
|
|
error = read_code(bprm->file, text_addr, 32, |
|
ex.a_text + ex.a_data); |
|
if ((signed long)error < 0) |
|
return error; |
|
} else { |
|
#ifdef WARN_OLD |
|
static unsigned long error_time, error_time2; |
|
if ((ex.a_text & 0xfff || ex.a_data & 0xfff) && |
|
(N_MAGIC(ex) != NMAGIC) && |
|
time_after(jiffies, error_time2 + 5*HZ)) { |
|
printk(KERN_NOTICE "executable not page aligned\n"); |
|
error_time2 = jiffies; |
|
} |
|
|
|
if ((fd_offset & ~PAGE_MASK) != 0 && |
|
time_after(jiffies, error_time + 5*HZ)) { |
|
printk(KERN_WARNING |
|
"fd_offset is not page aligned. Please convert " |
|
"program: %pD\n", |
|
bprm->file); |
|
error_time = jiffies; |
|
} |
|
#endif |
|
|
|
if (!bprm->file->f_op->mmap || (fd_offset & ~PAGE_MASK) != 0) { |
|
error = vm_brk(N_TXTADDR(ex), ex.a_text+ex.a_data); |
|
if (error) |
|
return error; |
|
|
|
read_code(bprm->file, N_TXTADDR(ex), fd_offset, |
|
ex.a_text+ex.a_data); |
|
goto beyond_if; |
|
} |
|
|
|
error = vm_mmap(bprm->file, N_TXTADDR(ex), ex.a_text, |
|
PROT_READ | PROT_EXEC, |
|
MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | |
|
MAP_EXECUTABLE | MAP_32BIT, |
|
fd_offset); |
|
|
|
if (error != N_TXTADDR(ex)) |
|
return error; |
|
|
|
error = vm_mmap(bprm->file, N_DATADDR(ex), ex.a_data, |
|
PROT_READ | PROT_WRITE | PROT_EXEC, |
|
MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | |
|
MAP_EXECUTABLE | MAP_32BIT, |
|
fd_offset + ex.a_text); |
|
if (error != N_DATADDR(ex)) |
|
return error; |
|
} |
|
|
|
beyond_if: |
|
error = set_brk(current->mm->start_brk, current->mm->brk); |
|
if (error) |
|
return error; |
|
|
|
set_binfmt(&aout_format); |
|
|
|
current->mm->start_stack = |
|
(unsigned long)create_aout_tables((char __user *)bprm->p, bprm); |
|
/* start thread */ |
|
loadsegment(fs, 0); |
|
loadsegment(ds, __USER32_DS); |
|
loadsegment(es, __USER32_DS); |
|
load_gs_index(0); |
|
(regs)->ip = ex.a_entry; |
|
(regs)->sp = current->mm->start_stack; |
|
(regs)->flags = 0x200; |
|
(regs)->cs = __USER32_CS; |
|
(regs)->ss = __USER32_DS; |
|
regs->r8 = regs->r9 = regs->r10 = regs->r11 = |
|
regs->r12 = regs->r13 = regs->r14 = regs->r15 = 0; |
|
return 0; |
|
} |
|
|
|
static int load_aout_library(struct file *file) |
|
{ |
|
unsigned long bss, start_addr, len, error; |
|
int retval; |
|
struct exec ex; |
|
loff_t pos = 0; |
|
|
|
retval = -ENOEXEC; |
|
error = kernel_read(file, &ex, sizeof(ex), &pos); |
|
if (error != sizeof(ex)) |
|
goto out; |
|
|
|
/* We come in here for the regular a.out style of shared libraries */ |
|
if ((N_MAGIC(ex) != ZMAGIC && N_MAGIC(ex) != QMAGIC) || N_TRSIZE(ex) || |
|
N_DRSIZE(ex) || ((ex.a_entry & 0xfff) && N_MAGIC(ex) == ZMAGIC) || |
|
i_size_read(file_inode(file)) < |
|
ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) { |
|
goto out; |
|
} |
|
|
|
if (N_FLAGS(ex)) |
|
goto out; |
|
|
|
/* For QMAGIC, the starting address is 0x20 into the page. We mask |
|
this off to get the starting address for the page */ |
|
|
|
start_addr = ex.a_entry & 0xfffff000; |
|
|
|
if ((N_TXTOFF(ex) & ~PAGE_MASK) != 0) { |
|
#ifdef WARN_OLD |
|
static unsigned long error_time; |
|
if (time_after(jiffies, error_time + 5*HZ)) { |
|
printk(KERN_WARNING |
|
"N_TXTOFF is not page aligned. Please convert " |
|
"library: %pD\n", |
|
file); |
|
error_time = jiffies; |
|
} |
|
#endif |
|
retval = vm_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss); |
|
if (retval) |
|
goto out; |
|
|
|
read_code(file, start_addr, N_TXTOFF(ex), |
|
ex.a_text + ex.a_data); |
|
retval = 0; |
|
goto out; |
|
} |
|
/* Now use mmap to map the library into memory. */ |
|
error = vm_mmap(file, start_addr, ex.a_text + ex.a_data, |
|
PROT_READ | PROT_WRITE | PROT_EXEC, |
|
MAP_FIXED | MAP_PRIVATE | MAP_DENYWRITE | MAP_32BIT, |
|
N_TXTOFF(ex)); |
|
retval = error; |
|
if (error != start_addr) |
|
goto out; |
|
|
|
len = PAGE_ALIGN(ex.a_text + ex.a_data); |
|
bss = ex.a_text + ex.a_data + ex.a_bss; |
|
if (bss > len) { |
|
retval = vm_brk(start_addr + len, bss - len); |
|
if (retval) |
|
goto out; |
|
} |
|
retval = 0; |
|
out: |
|
return retval; |
|
} |
|
|
|
static int __init init_aout_binfmt(void) |
|
{ |
|
register_binfmt(&aout_format); |
|
return 0; |
|
} |
|
|
|
static void __exit exit_aout_binfmt(void) |
|
{ |
|
unregister_binfmt(&aout_format); |
|
} |
|
|
|
module_init(init_aout_binfmt); |
|
module_exit(exit_aout_binfmt); |
|
MODULE_LICENSE("GPL");
|
|
|