1 files changed, 24 insertions, 7 deletions

diff --git a/fs/exec.c b/fs/exec.c
index 675c3f44c2ea..e95c692ef0e4 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -571,6 +571,9 @@ int setup_arg_pages(struct linux_binprm *bprm,
         struct vm_area_struct *prev = NULL;
         unsigned long vm_flags;
         unsigned long stack_base;
+        unsigned long stack_size;
+        unsigned long stack_expand;
+        unsigned long rlim_stack;
 
 #ifdef CONFIG_STACK_GROWSUP
         /* Limit stack size to 1GB */
@@ -627,10 +630,24 @@ int setup_arg_pages(struct linux_binprm *bprm,
                         goto out_unlock;
         }
 
+        stack_expand = EXTRA_STACK_VM_PAGES * PAGE_SIZE;
+        stack_size = vma->vm_end - vma->vm_start;
+        /*
+         * Align this down to a page boundary as expand_stack
+         * will align it up.
+         */
+        rlim_stack = rlimit(RLIMIT_STACK) & PAGE_MASK;
+        rlim_stack = min(rlim_stack, stack_size);
 #ifdef CONFIG_STACK_GROWSUP
-        stack_base = vma->vm_end + EXTRA_STACK_VM_PAGES * PAGE_SIZE;
+        if (stack_size + stack_expand > rlim_stack)
+                stack_base = vma->vm_start + rlim_stack;
+        else
+                stack_base = vma->vm_end + stack_expand;
 #else
-        stack_base = vma->vm_start - EXTRA_STACK_VM_PAGES * PAGE_SIZE;
+        if (stack_size + stack_expand > rlim_stack)
+                stack_base = vma->vm_end - rlim_stack;
+        else
+                stack_base = vma->vm_start - stack_expand;
 #endif
         ret = expand_stack(vma, stack_base);
         if (ret)
@@ -961,6 +978,11 @@ int flush_old_exec(struct linux_binprm * bprm)
                 goto out;
 
         bprm->mm = NULL;                /* We're using it now */
+
+        current->flags &= ~PF_RANDOMIZE;
+        flush_thread();
+        current->personality &= ~bprm->per_clear;
+
         return 0;
 
 out:
@@ -997,9 +1019,6 @@ void setup_new_exec(struct linux_binprm * bprm)
         tcomm[i] = '\0';
         set_task_comm(current, tcomm);
 
-        current->flags &= ~PF_RANDOMIZE;
-        flush_thread();
-
         /* Set the new mm task size. We have to do that late because it may
          * depend on TIF_32BIT which is only updated in flush_thread() on
          * some architectures like powerpc
@@ -1015,8 +1034,6 @@ void setup_new_exec(struct linux_binprm * bprm)
                 set_dumpable(current->mm, suid_dumpable);
         }
 
-        current->personality &= ~bprm->per_clear;
-
         /*
          * Flush performance counters when crossing a
          * security domain: