diff options
Diffstat (limited to 'arch/x86/ia32/ia32_aout.c')
| -rw-r--r-- | arch/x86/ia32/ia32_aout.c | 528 |
1 files changed, 528 insertions, 0 deletions
diff --git a/arch/x86/ia32/ia32_aout.c b/arch/x86/ia32/ia32_aout.c new file mode 100644 index 00000000000..08781370256 --- /dev/null +++ b/arch/x86/ia32/ia32_aout.c @@ -0,0 +1,528 @@ +/* + * 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/slab.h> +#include <linux/binfmts.h> +#include <linux/personality.h> +#include <linux/init.h> + +#include <asm/system.h> +#include <asm/uaccess.h> +#include <asm/pgalloc.h> +#include <asm/cacheflush.h> +#include <asm/user32.h> +#include <asm/ia32.h> + +#undef WARN_OLD +#undef CORE_DUMP /* probably broken */ + +static int load_aout_binary(struct linux_binprm *, struct pt_regs * regs); +static int load_aout_library(struct file*); + +#ifdef CORE_DUMP +static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file); + +/* + * fill in the user structure for a core dump.. + */ +static void dump_thread32(struct pt_regs * regs, struct user32 * dump) +{ + u32 fs,gs; + +/* changed the size calculations - should hopefully work better. lbt */ + dump->magic = CMAGIC; + dump->start_code = 0; + dump->start_stack = regs->rsp & ~(PAGE_SIZE - 1); + dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT; + dump->u_dsize = ((unsigned long) (current->mm->brk + (PAGE_SIZE-1))) >> PAGE_SHIFT; + dump->u_dsize -= dump->u_tsize; + dump->u_ssize = 0; + dump->u_debugreg[0] = current->thread.debugreg0; + dump->u_debugreg[1] = current->thread.debugreg1; + dump->u_debugreg[2] = current->thread.debugreg2; + dump->u_debugreg[3] = current->thread.debugreg3; + dump->u_debugreg[4] = 0; + dump->u_debugreg[5] = 0; + dump->u_debugreg[6] = current->thread.debugreg6; + dump->u_debugreg[7] = current->thread.debugreg7; + + if (dump->start_stack < 0xc0000000) + dump->u_ssize = ((unsigned long) (0xc0000000 - dump->start_stack)) >> PAGE_SHIFT; + + dump->regs.ebx = regs->rbx; + dump->regs.ecx = regs->rcx; + dump->regs.edx = regs->rdx; + dump->regs.esi = regs->rsi; + dump->regs.edi = regs->rdi; + dump->regs.ebp = regs->rbp; + dump->regs.eax = regs->rax; + dump->regs.ds = current->thread.ds; + dump->regs.es = current->thread.es; + asm("movl %%fs,%0" : "=r" (fs)); dump->regs.fs = fs; + asm("movl %%gs,%0" : "=r" (gs)); dump->regs.gs = gs; + dump->regs.orig_eax = regs->orig_rax; + dump->regs.eip = regs->rip; + dump->regs.cs = regs->cs; + dump->regs.eflags = regs->eflags; + dump->regs.esp = regs->rsp; + dump->regs.ss = regs->ss; + +#if 1 /* FIXME */ + dump->u_fpvalid = 0; +#else + dump->u_fpvalid = dump_fpu (regs, &dump->i387); +#endif +} + +#endif + +static struct linux_binfmt aout_format = { + .module = THIS_MODULE, + .load_binary = load_aout_binary, + .load_shlib = load_aout_library, +#ifdef CORE_DUMP + .core_dump = aout_core_dump, +#endif + .min_coredump = PAGE_SIZE +}; + +static void set_brk(unsigned long start, unsigned long end) +{ + start = PAGE_ALIGN(start); + end = PAGE_ALIGN(end); + if (end <= start) + return; + down_write(¤t->mm->mmap_sem); + do_brk(start, end - start); + up_write(¤t->mm->mmap_sem); +} + +#ifdef CORE_DUMP +/* + * These are the only things you should do on a core-file: use only these + * macros to write out all the necessary info. + */ + +static int dump_write(struct file *file, const void *addr, int nr) +{ + return file->f_op->write(file, addr, nr, &file->f_pos) == nr; +} + +#define DUMP_WRITE(addr, nr) \ + if (!dump_write(file, (void *)(addr), (nr))) \ + goto end_coredump; + +#define DUMP_SEEK(offset) \ +if (file->f_op->llseek) { \ + if (file->f_op->llseek(file,(offset),0) != (offset)) \ + goto end_coredump; \ +} else file->f_pos = (offset) + +/* + * Routine writes a core dump image in the current directory. + * Currently only a stub-function. + * + * Note that setuid/setgid files won't make a core-dump if the uid/gid + * changed due to the set[u|g]id. It's enforced by the "current->mm->dumpable" + * field, which also makes sure the core-dumps won't be recursive if the + * dumping of the process results in another error.. + */ + +static int aout_core_dump(long signr, struct pt_regs * regs, struct file *file) +{ + mm_segment_t fs; + int has_dumped = 0; + unsigned long dump_start, dump_size; + struct user32 dump; +# define START_DATA(u) (u.u_tsize << PAGE_SHIFT) +# define START_STACK(u) (u.start_stack) + + fs = get_fs(); + set_fs(KERNEL_DS); + has_dumped = 1; + current->flags |= PF_DUMPCORE; + strncpy(dump.u_comm, current->comm, sizeof(current->comm)); + dump.u_ar0 = (u32)(((unsigned long)(&dump.regs)) - ((unsigned long)(&dump))); + dump.signal = signr; + dump_thread32(regs, &dump); + +/* If the size of the dump file exceeds the rlimit, then see what would happen + if we wrote the stack, but not the data area. */ + if ((dump.u_dsize+dump.u_ssize+1) * PAGE_SIZE > + current->signal->rlim[RLIMIT_CORE].rlim_cur) + dump.u_dsize = 0; + +/* Make sure we have enough room to write the stack and data areas. */ + if ((dump.u_ssize+1) * PAGE_SIZE > + current->signal->rlim[RLIMIT_CORE].rlim_cur) + dump.u_ssize = 0; + +/* make sure we actually have a data and stack area to dump */ + set_fs(USER_DS); + if (!access_ok(VERIFY_READ, (void *) (unsigned long)START_DATA(dump), dump.u_dsize << PAGE_SHIFT)) + dump.u_dsize = 0; + if (!access_ok(VERIFY_READ, (void *) (unsigned long)START_STACK(dump), dump.u_ssize << PAGE_SHIFT)) + dump.u_ssize = 0; + + set_fs(KERNEL_DS); +/* struct user */ + DUMP_WRITE(&dump,sizeof(dump)); +/* Now dump all of the user data. Include malloced stuff as well */ + DUMP_SEEK(PAGE_SIZE); +/* now we start writing out the user space info */ + set_fs(USER_DS); +/* Dump the data area */ + if (dump.u_dsize != 0) { + dump_start = START_DATA(dump); + dump_size = dump.u_dsize << PAGE_SHIFT; + DUMP_WRITE(dump_start,dump_size); + } +/* Now prepare to dump the stack area */ + if (dump.u_ssize != 0) { + dump_start = START_STACK(dump); + dump_size = dump.u_ssize << PAGE_SHIFT; + DUMP_WRITE(dump_start,dump_size); + } +/* Finally dump the task struct. Not be used by gdb, but could be useful */ + set_fs(KERNEL_DS); + DUMP_WRITE(current,sizeof(*current)); +end_coredump: + set_fs(fs); + return has_dumped; +} +#endif + +/* + * 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; + u32 __user *envp; + u32 __user *sp; + int argc = bprm->argc; + int 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, struct pt_regs * regs) +{ + struct exec ex; + unsigned long error; + unsigned long fd_offset; + unsigned long rlim; + 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(bprm->file->f_path.dentry->d_inode) < 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 = current->signal->rlim[RLIMIT_DATA].rlim_cur; + 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 = flush_old_exec(bprm); + if (retval) + return retval; + + regs->cs = __USER32_CS; + regs->r8 = regs->r9 = regs->r10 = regs->r11 = regs->r12 = + regs->r13 = regs->r14 = regs->r15 = 0; + + /* OK, This is the point of no return */ + set_personality(PER_LINUX); + set_thread_flag(TIF_IA32); + clear_thread_flag(TIF_ABI_PENDING); + + 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)); + current->mm->free_area_cache = TASK_UNMAPPED_BASE; + current->mm->cached_hole_size = 0; + + current->mm->mmap = NULL; + compute_creds(bprm); + current->flags &= ~PF_FORKNOEXEC; + + if (N_MAGIC(ex) == OMAGIC) { + unsigned long text_addr, map_size; + loff_t pos; + + text_addr = N_TXTADDR(ex); + + pos = 32; + map_size = ex.a_text+ex.a_data; + + down_write(¤t->mm->mmap_sem); + error = do_brk(text_addr & PAGE_MASK, map_size); + up_write(¤t->mm->mmap_sem); + + if (error != (text_addr & PAGE_MASK)) { + send_sig(SIGKILL, current, 0); + return error; + } + + error = bprm->file->f_op->read(bprm->file, + (char __user *)text_addr, + ex.a_text+ex.a_data, &pos); + if ((signed long)error < 0) { + send_sig(SIGKILL, current, 0); + return error; + } + + flush_icache_range(text_addr, text_addr+ex.a_text+ex.a_data); + } else { +#ifdef WARN_OLD + static unsigned long error_time, error_time2; + if ((ex.a_text & 0xfff || ex.a_data & 0xfff) && + (N_MAGIC(ex) != NMAGIC) && (jiffies-error_time2) > 5*HZ) + { + printk(KERN_NOTICE "executable not page aligned\n"); + error_time2 = jiffies; + } + + if ((fd_offset & ~PAGE_MASK) != 0 && + (jiffies-error_time) > 5*HZ) + { + printk(KERN_WARNING + "fd_offset is not page aligned. Please convert program: %s\n", + bprm->file->f_path.dentry->d_name.name); + error_time = jiffies; + } +#endif + + if (!bprm->file->f_op->mmap||((fd_offset & ~PAGE_MASK) != 0)) { + loff_t pos = fd_offset; + down_write(¤t->mm->mmap_sem); + do_brk(N_TXTADDR(ex), ex.a_text+ex.a_data); + up_write(¤t->mm->mmap_sem); + bprm->file->f_op->read(bprm->file, + (char __user *)N_TXTADDR(ex), + ex.a_text+ex.a_data, &pos); + flush_icache_range((unsigned long) N_TXTADDR(ex), + (unsigned long) N_TXTADDR(ex) + + ex.a_text+ex.a_data); + goto beyond_if; + } + + down_write(¤t->mm->mmap_sem); + error = do_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); + up_write(¤t->mm->mmap_sem); + + if (error != N_TXTADDR(ex)) { + send_sig(SIGKILL, current, 0); + return error; + } + + down_write(¤t->mm->mmap_sem); + error = do_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); + up_write(¤t->mm->mmap_sem); + if (error != N_DATADDR(ex)) { + send_sig(SIGKILL, current, 0); + return error; + } + } +beyond_if: + set_binfmt(&aout_format); + + set_brk(current->mm->start_brk, current->mm->brk); + + retval = setup_arg_pages(bprm, IA32_STACK_TOP, EXSTACK_DEFAULT); + if (retval < 0) { + /* Someone check-me: is this error path enough? */ + send_sig(SIGKILL, current, 0); + return retval; + } + + current->mm->start_stack = + (unsigned long)create_aout_tables((char __user *)bprm->p, bprm); + /* start thread */ + asm volatile("movl %0,%%fs" :: "r" (0)); \ + asm volatile("movl %0,%%es; movl %0,%%ds": :"r" (__USER32_DS)); + load_gs_index(0); + (regs)->rip = ex.a_entry; + (regs)->rsp = current->mm->start_stack; + (regs)->eflags = 0x200; + (regs)->cs = __USER32_CS; + (regs)->ss = __USER32_DS; + set_fs(USER_DS); + if (unlikely(current->ptrace & PT_PTRACED)) { + if (current->ptrace & PT_TRACE_EXEC) + ptrace_notify ((PTRACE_EVENT_EXEC << 8) | SIGTRAP); + else + send_sig(SIGTRAP, current, 0); + } + return 0; +} + +static int load_aout_library(struct file *file) +{ + struct inode * inode; + unsigned long bss, start_addr, len; + unsigned long error; + int retval; + struct exec ex; + + inode = file->f_path.dentry->d_inode; + + retval = -ENOEXEC; + error = kernel_read(file, 0, (char *) &ex, sizeof(ex)); + 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(inode) < 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) { + loff_t pos = N_TXTOFF(ex); + +#ifdef WARN_OLD + static unsigned long error_time; + if ((jiffies-error_time) > 5*HZ) + { + printk(KERN_WARNING + "N_TXTOFF is not page aligned. Please convert library: %s\n", + file->f_path.dentry->d_name.name); + error_time = jiffies; + } +#endif + down_write(¤t->mm->mmap_sem); + do_brk(start_addr, ex.a_text + ex.a_data + ex.a_bss); + up_write(¤t->mm->mmap_sem); + + file->f_op->read(file, (char __user *)start_addr, + ex.a_text + ex.a_data, &pos); + flush_icache_range((unsigned long) start_addr, + (unsigned long) start_addr + ex.a_text + ex.a_data); + + retval = 0; + goto out; + } + /* Now use mmap to map the library into memory. */ + down_write(¤t->mm->mmap_sem); + error = do_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)); + up_write(¤t->mm->mmap_sem); + 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) { + down_write(¤t->mm->mmap_sem); + error = do_brk(start_addr + len, bss - len); + up_write(¤t->mm->mmap_sem); + retval = error; + if (error != start_addr + len) + goto out; + } + retval = 0; +out: + return retval; +} + +static int __init init_aout_binfmt(void) +{ + return register_binfmt(&aout_format); +} + +static void __exit exit_aout_binfmt(void) +{ + unregister_binfmt(&aout_format); +} + +module_init(init_aout_binfmt); +module_exit(exit_aout_binfmt); +MODULE_LICENSE("GPL"); |