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diff -Nru linux-2.4.28/fs/binfmt_aout.c linux-2.4.28-hardened/fs/binfmt_aout.c
--- linux-2.4.28/fs/binfmt_aout.c 2004-11-28 15:44:03.000000000 -0500
+++ linux-2.4.28-hardened/fs/binfmt_aout.c 2004-11-28 16:05:16.000000000 -0500
@@ -39,13 +39,18 @@
NULL, THIS_MODULE, load_aout_binary, load_aout_library, aout_core_dump, PAGE_SIZE
};
-static void set_brk(unsigned long start, unsigned long end)
+#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;
- do_brk(start, end - start);
+ if (end > start) {
+ unsigned long addr = do_brk(start, end - start);
+ if (BAD_ADDR(addr))
+ return addr;
+ }
+ return 0;
}
/*
@@ -429,7 +434,11 @@
beyond_if:
set_binfmt(&aout_format);
- set_brk(current->mm->start_brk, current->mm->brk);
+ retval = set_brk(current->mm->start_brk, current->mm->brk);
+ if (retval < 0) {
+ send_sig(SIGKILL, current, 0);
+ return retval;
+ }
retval = setup_arg_pages(bprm);
if (retval < 0) {
diff -Nru linux-2.4.28/fs/exec.c linux-2.4.28-hardened/fs/exec.c
--- linux-2.4.28/fs/exec.c 2004-11-28 15:44:03.000000000 -0500
+++ linux-2.4.28-hardened/fs/exec.c 2004-11-28 16:05:16.000000000 -0500
@@ -387,6 +387,7 @@
down_write(¤t->mm->mmap_sem);
{
+ struct vm_area_struct *vma;
mpnt->vm_mm = current->mm;
mpnt->vm_start = PAGE_MASK & (unsigned long) bprm->p;
mpnt->vm_end = STACK_TOP;
@@ -401,6 +402,12 @@
mpnt->vm_pgoff = 0;
mpnt->vm_file = NULL;
mpnt->vm_private_data = (void *) 0;
+ vma = find_vma(current->mm, mpnt->vm_start);
+ if (vma) {
+ up_write(¤t->mm->mmap_sem);
+ kmem_cache_free(vm_area_cachep, mpnt);
+ return -ENOMEM;
+ }
insert_vm_struct(current->mm, mpnt);
current->mm->total_vm = (mpnt->vm_end - mpnt->vm_start) >> PAGE_SHIFT;
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