From c2316dbf124257ae19fd2e29cb5ec51060649d38 Mon Sep 17 00:00:00 2001 From: Stephen Smalley <sds@tycho.nsa.gov> Date: Fri, 8 Apr 2016 13:55:03 -0400 Subject: [PATCH] selinux: apply execstack check on thread stacks The execstack check was only being applied on the main process stack. Thread stacks allocated via mmap were only subject to the execmem permission check. Augment the check to apply to the current thread stack as well. Note that this does NOT prevent making a different thread's stack executable. Suggested-by: Nick Kralevich <nnk@google.com> Acked-by: Nick Kralevich <nnk@google.com> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com> --- security/selinux/hooks.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index bbff80c6d3f2..a00ab81ab719 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -3479,8 +3479,9 @@ static int selinux_file_mprotect(struct vm_area_struct *vma, vma->vm_end <= vma->vm_mm->brk) { rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP); } else if (!vma->vm_file && - vma->vm_start <= vma->vm_mm->start_stack && - vma->vm_end >= vma->vm_mm->start_stack) { + ((vma->vm_start <= vma->vm_mm->start_stack && + vma->vm_end >= vma->vm_mm->start_stack) || + vma_is_stack_for_task(vma, current))) { rc = current_has_perm(current, PROCESS__EXECSTACK); } else if (vma->vm_file && vma->anon_vma) { /* -- 2.30.9