From e006043a4d2da52bba9fd9cb7e5a22e2951ff69b Mon Sep 17 00:00:00 2001 From: Jack Steiner Date: Tue, 15 Dec 2009 16:48:10 -0800 Subject: [PATCH] gru: check for valid vma Fix bug caused by failure to allocate a GRU gts structure. The old code failed to handle the case where the vma was invalid. Signed-off-by: Jack Steiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/misc/sgi-gru/grufault.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/drivers/misc/sgi-gru/grufault.c b/drivers/misc/sgi-gru/grufault.c index ada7df7e0968..7466234450f3 100644 --- a/drivers/misc/sgi-gru/grufault.c +++ b/drivers/misc/sgi-gru/grufault.c @@ -90,19 +90,22 @@ static struct gru_thread_state *gru_alloc_locked_gts(unsigned long vaddr) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma; - struct gru_thread_state *gts = NULL; + struct gru_thread_state *gts = ERR_PTR(-EINVAL); down_write(&mm->mmap_sem); vma = gru_find_vma(vaddr); - if (vma) - gts = gru_alloc_thread_state(vma, TSID(vaddr, vma)); - if (!IS_ERR(gts)) { - mutex_lock(>s->ts_ctxlock); - downgrade_write(&mm->mmap_sem); - } else { - up_write(&mm->mmap_sem); - } + if (!vma) + goto err; + gts = gru_alloc_thread_state(vma, TSID(vaddr, vma)); + if (IS_ERR(gts)) + goto err; + mutex_lock(>s->ts_ctxlock); + downgrade_write(&mm->mmap_sem); + return gts; + +err: + up_write(&mm->mmap_sem); return gts; }