From 73ae31e5986a4c0ee84bfd13ccd9b57a98956f6f Mon Sep 17 00:00:00 2001 From: Eric B Munson Date: Thu, 13 Jan 2011 15:47:28 -0800 Subject: [PATCH] hugetlb: fix handling of parse errors in sysfs When parsing changes to the huge page pool sizes made from userspace via the sysfs interface, bogus input values are being covered up by nr_hugepages_store_common and nr_overcommit_hugepages_store returning 0 when strict_strtoul returns an error. This can cause an infinite loop in the nr_hugepages_store code. This patch changes the return value for these functions to -EINVAL when strict_strtoul returns an error. Signed-off-by: Eric B Munson Reported-by: CAI Qian Cc: Andrea Arcangeli Cc: Eric B Munson Cc: Michal Hocko Cc: Nishanth Aravamudan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index ce8e5bb6f03..bb0b7c12801 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1375,10 +1375,8 @@ static ssize_t nr_hugepages_store_common(bool obey_mempolicy, NODEMASK_ALLOC(nodemask_t, nodes_allowed, GFP_KERNEL | __GFP_NORETRY); err = strict_strtoul(buf, 10, &count); - if (err) { - err = 0; /* This seems wrong */ + if (err) goto out; - } h = kobj_to_hstate(kobj, &nid); if (h->order >= MAX_ORDER) { @@ -1469,7 +1467,7 @@ static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj, err = strict_strtoul(buf, 10, &input); if (err) - return 0; + return err; spin_lock(&hugetlb_lock); h->nr_overcommit_huge_pages = input; -- 2.20.1