From 05fa199d45c54a9bda7aa3ae6537253d6f097aa9 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Thu, 16 Apr 2009 21:58:12 +0100 Subject: [PATCH] mm: pass correct mm when growing stack Tetsuo Handa reports seeing the WARN_ON(current->mm == NULL) in security_vm_enough_memory(), when do_execve() is touching the target mm's stack, to set up its args and environment. Yes, a UMH_NO_WAIT or UMH_WAIT_PROC call_usermodehelper() spawns an mm-less kernel thread to do the exec. And in any case, that vm_enough_memory check when growing stack ought to be done on the target mm, not on the execer's mm (though apart from the warning, it only makes a slight tweak to OVERCOMMIT_NEVER behaviour). Reported-by: Tetsuo Handa Signed-off-by: Hugh Dickins Cc: stable@kernel.org Signed-off-by: Linus Torvalds --- mm/mmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/mmap.c b/mm/mmap.c index 4a3841186c11..3303d1ba8e87 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1575,7 +1575,7 @@ static int acct_stack_growth(struct vm_area_struct *vma, unsigned long size, uns * Overcommit.. This must be the final test, as it will * update security statistics. */ - if (security_vm_enough_memory(grow)) + if (security_vm_enough_memory_mm(mm, grow)) return -ENOMEM; /* Ok, everything looks good - let it rip */