x86: Remove a.out support
authorBorislav Petkov <bp@suse.de>
Thu, 13 Jan 2022 13:26:10 +0000 (14:26 +0100)
committerBorislav Petkov <bp@suse.de>
Mon, 11 Apr 2022 16:04:27 +0000 (18:04 +0200)
Commit

  eac616557050 ("x86: Deprecate a.out support")

deprecated a.out support with the promise to remove it a couple of
releases later. That commit landed in v5.1.

Now it is more than a couple of releases later, no one has complained so
remove it.

Fold in a hunk removing the reference to arch/x86/ia32/ia32_aout.c in
MAINTAINERS:

  https://lore.kernel.org/r/20220316050828.17255-1-lukas.bulwahn@gmail.com

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20220113160115.5375-1-bp@alien8.de
MAINTAINERS
arch/x86/Kconfig
arch/x86/ia32/Makefile
arch/x86/ia32/ia32_aout.c [deleted file]

index fd768d43e048299a0cb36fefc86e78fe0388c98f..795e4c7ed7a64b8b77d8710cdf26a48fe332e2b7 100644 (file)
@@ -7378,7 +7378,6 @@ L:        linux-mm@kvack.org
 S:     Supported
 T:     git git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git for-next/execve
 F:     arch/alpha/kernel/binfmt_loader.c
-F:     arch/x86/ia32/ia32_aout.c
 F:     fs/*binfmt_*.c
 F:     fs/exec.c
 F:     include/linux/binfmts.h
index b0142e01002e3dd4fc3299f23da6ce2e6aaa3997..69231f66a2b51009fcc1c25a6dd53a6fab9ef3b5 100644 (file)
@@ -2838,13 +2838,6 @@ config IA32_EMULATION
          64-bit kernel. You should likely turn this on, unless you're
          100% sure that you don't have any 32-bit programs left.
 
-config IA32_AOUT
-       tristate "IA32 a.out support"
-       depends on IA32_EMULATION
-       depends on BROKEN
-       help
-         Support old a.out binaries in the 32bit emulation.
-
 config X86_X32_ABI
        bool "x32 ABI for 64-bit mode"
        depends on X86_64
index 8e4d0391ff6c9bafa9bcb7dde33478bd6f569d09..e481056698de145f82c770ca9730168a46738dab 100644 (file)
@@ -5,7 +5,5 @@
 
 obj-$(CONFIG_IA32_EMULATION) := ia32_signal.o
 
-obj-$(CONFIG_IA32_AOUT) += ia32_aout.o
-
 audit-class-$(CONFIG_AUDIT) := audit.o
 obj-$(CONFIG_IA32_EMULATION) += $(audit-class-y)
diff --git a/arch/x86/ia32/ia32_aout.c b/arch/x86/ia32/ia32_aout.c
deleted file mode 100644 (file)
index 9bd1524..0000000
+++ /dev/null
@@ -1,325 +0,0 @@
-// 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_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_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_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");