a.out: Remove the a.out implementation

In commit 19e8b701e258 ("a.out: Stop building a.out/osf1 support on
alpha and m68k") the last users of a.out were disabled.

As nothing has turned up to cause this change to be reverted, let's
remove the code implementing a.out support as well.

There may be userspace users of the uapi bits left so the uapi
headers have been left untouched.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Arnd Bergmann <arnd@arndb.de> # arm defconfigs
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/871qrx3hq3.fsf@email.froward.int.ebiederm.org

1 files changed, 0 insertions, 342 deletions

diff --git a/fs/binfmt_aout.c b/fs/binfmt_aout.c
deleted file mode 100644
index 0dcfc691e7e2..000000000000
--- a/fs/binfmt_aout.c
+++ /dev/null
@@ -1,342 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- *  linux/fs/binfmt_aout.c
- *
- *  Copyright (C) 1991, 1992, 1996  Linus Torvalds
- */
-
-#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/coredump.h>
-#include <linux/slab.h>
-#include <linux/sched/task_stack.h>
-
-#include <linux/uaccess.h>
-#include <asm/cacheflush.h>
-
-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,
-};
-
-#define BAD_ADDR(x)	((unsigned long)(x) >= TASK_SIZE)
-
-static int set_brk(unsigned long start, unsigned long end)
-{
-	start = PAGE_ALIGN(start);
-	end = PAGE_ALIGN(end);
-	if (end > start)
-		return vm_brk(start, end - start);
-	return 0;
-}
-
-/*
- * 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 unsigned long __user *create_aout_tables(char __user *p, struct linux_binprm * bprm)
-{
-	char __user * __user *argv;
-	char __user * __user *envp;
-	unsigned long __user *sp;
-	int argc = bprm->argc;
-	int envc = bprm->envc;
-
-	sp = (void __user *)((-(unsigned long)sizeof(char *)) & (unsigned long) p);
-#ifdef __alpha__
-/* whee.. test-programs are so much fun. */
-	put_user(0, --sp);
-	put_user(0, --sp);
-	if (bprm->loader) {
-		put_user(0, --sp);
-		put_user(1003, --sp);
-		put_user(bprm->loader, --sp);
-		put_user(1002, --sp);
-	}
-	put_user(bprm->exec, --sp);
-	put_user(1001, --sp);
-#endif
-	sp -= envc+1;
-	envp = (char __user * __user *) sp;
-	sp -= argc+1;
-	argv = (char __user * __user *) sp;
-#ifndef __alpha__
-	put_user((unsigned long) envp,--sp);
-	put_user((unsigned long) argv,--sp);
-#endif
-	put_user(argc,--sp);
-	current->mm->arg_start = (unsigned long) p;
-	while (argc-->0) {
-		char c;
-		put_user(p,argv++);
-		do {
-			get_user(c,p++);
-		} while (c);
-	}
-	put_user(NULL,argv);
-	current->mm->arg_end = current->mm->env_start = (unsigned long) p;
-	while (envc-->0) {
-		char c;
-		put_user(p,envp++);
-		do {
-			get_user(c,p++);
-		} while (c);
-	}
-	put_user(NULL,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 = current_pt_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(file_inode(bprm->file)) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
-		return -ENOEXEC;
-	}
-
-	/*
-	 * Requires a mmap handler. This prevents people from using a.out
-	 * as part of an exploit attack against /proc-related vulnerabilities.
-	 */
-	if (!bprm->file->f_op->mmap)
-		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 */
-#ifdef __alpha__
-	SET_AOUT_PERSONALITY(bprm, ex);
-#else
-	set_personality(PER_LINUX);
-#endif
-	setup_new_exec(bprm);
-
-	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, STACK_TOP, EXSTACK_DEFAULT);
-	if (retval < 0)
-		return retval;
-
-
-	if (N_MAGIC(ex) == OMAGIC) {
-		unsigned long text_addr, map_size;
-		loff_t pos;
-
-		text_addr = N_TXTADDR(ex);
-
-#ifdef __alpha__
-		pos = fd_offset;
-		map_size = ex.a_text+ex.a_data + PAGE_SIZE - 1;
-#else
-		pos = 32;
-		map_size = ex.a_text+ex.a_data;
-#endif
-		error = vm_brk(text_addr & PAGE_MASK, map_size);
-		if (error)
-			return error;
-
-		error = read_code(bprm->file, text_addr, pos,
-				  ex.a_text+ex.a_data);
-		if ((signed long)error < 0)
-			return error;
-	} else {
-		if ((ex.a_text & 0xfff || ex.a_data & 0xfff) &&
-		    (N_MAGIC(ex) != NMAGIC) && printk_ratelimit())
-		{
-			printk(KERN_NOTICE "executable not page aligned\n");
-		}
-
-		if ((fd_offset & ~PAGE_MASK) != 0 && printk_ratelimit())
-		{
-			printk(KERN_WARNING 
-			       "fd_offset is not page aligned. Please convert program: %pD\n",
-			       bprm->file);
-		}
-
-		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,
-			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,
-				fd_offset + ex.a_text);
-		if (error != N_DATADDR(ex))
-			return error;
-	}
-beyond_if:
-	set_binfmt(&aout_format);
-
-	retval = set_brk(current->mm->start_brk, current->mm->brk);
-	if (retval < 0)
-		return retval;
-
-	current->mm->start_stack =
-		(unsigned long) create_aout_tables((char __user *) bprm->p, bprm);
-#ifdef __alpha__
-	regs->gp = ex.a_gpvalue;
-#endif
-	finalize_exec(bprm);
-	start_thread(regs, ex.a_entry, current->mm->start_stack);
-	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;
-	loff_t pos = 0;
-
-	inode = file_inode(file);
-
-	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(inode) < ex.a_text+ex.a_data+N_SYMSIZE(ex)+N_TXTOFF(ex)) {
-		goto out;
-	}
-
-	/*
-	 * Requires a mmap handler. This prevents people from using a.out
-	 * as part of an exploit attack against /proc-related vulnerabilities.
-	 */
-	if (!file->f_op->mmap)
-		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) {
-		if (printk_ratelimit())
-		{
-			printk(KERN_WARNING 
-			       "N_TXTOFF is not page aligned. Please convert library: %pD\n",
-			       file);
-		}
-		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,
-			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);
-}
-
-core_initcall(init_aout_binfmt);
-module_exit(exit_aout_binfmt);
-MODULE_LICENSE("GPL");