[PATCH] Fix handling of parse errors in sysctl

[Eric B Munson]

This patch is a candidate for stable.

==== CUT HERE ====

When parsing changes to the huge page pool sizes made from userspace
via the sysctl 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 patch changes
the return value for these functions to -EINVAL when strict_strtoul
returns an error.

Reported-by: CAI Qian <caiqian@xxxxxxxxxx>

Signed-off-by: Eric B Munson <emunson@xxxxxxxxx>
---
 mm/hugetlb.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 8585524..5cb71a9 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1440,7 +1440,7 @@ static ssize_t nr_hugepages_store_common(bool obey_mempolicy,
 
 	err = strict_strtoul(buf, 10, &count);
 	if (err)
-		return 0;
+		return -EINVAL;
 
 	h = kobj_to_hstate(kobj, &nid);
 	if (nid == NUMA_NO_NODE) {
@@ -1519,7 +1519,7 @@ static ssize_t nr_overcommit_hugepages_store(struct kobject *kobj,
 
 	err = strict_strtoul(buf, 10, &input);
 	if (err)
-		return 0;
+		return -EINVAL;
 
 	spin_lock(&hugetlb_lock);
 	h->nr_overcommit_huge_pages = input;
-- 
1.7.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/