From 20cbc972617069c1ed434f62151e4de57d26ea46 Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Sat, 5 Jul 2008 12:29:05 -0700 Subject: [PATCH] Fix clear_refs_write() use of struct mm_walk Don't use a static entry, so as to prevent races during concurrent use of this function. Reported-by: Alexey Dobriyan Cc: Matt Mackall Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/proc/task_mmu.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index ab8ccc9..05053d70 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -476,10 +476,10 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf, return -ESRCH; mm = get_task_mm(task); if (mm) { - static struct mm_walk clear_refs_walk; - memset(&clear_refs_walk, 0, sizeof(clear_refs_walk)); - clear_refs_walk.pmd_entry = clear_refs_pte_range; - clear_refs_walk.mm = mm; + struct mm_walk clear_refs_walk = { + .pmd_entry = clear_refs_pte_range, + .mm = mm, + }; down_read(&mm->mmap_sem); for (vma = mm->mmap; vma; vma = vma->vm_next) { clear_refs_walk.private = vma; -- 2.7.4