[PATCH] small fix for not releasing the mmap semaphore in i386/arch_setup_additional_pages

the VDSO randomization code on i386 fails to release the mmap semaphore
if insert_vm_struct() fails.

[ Made the conditional unlikely. -- Linus ]

Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 4 insertions, 6 deletions

diff --git a/arch/i386/kernel/sysenter.c b/arch/i386/kernel/sysenter.c
index c60419dee018..713ba39d32c6 100644
--- a/arch/i386/kernel/sysenter.c
+++ b/arch/i386/kernel/sysenter.c
@@ -148,8 +148,10 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
         vma->vm_mm = mm;
 
         ret = insert_vm_struct(mm, vma);
-        if (ret)
-                goto free_vma;
+        if (unlikely(ret)) {
+                kmem_cache_free(vm_area_cachep, vma);
+                goto up_fail;
+        }
 
         current->mm->context.vdso = (void *)addr;
         current_thread_info()->sysenter_return =
@@ -158,10 +160,6 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
 up_fail:
         up_write(&mm->mmap_sem);
         return ret;
-
-free_vma:
-        kmem_cache_free(vm_area_cachep, vma);
-        return ret;
 }
 
 const char *arch_vma_name(struct vm_area_struct *vma)