From 4605f057aace9291e80bf9982cc7c8babc917f56 Mon Sep 17 00:00:00 2001 From: Wenchao Hao Date: Tue, 11 Aug 2020 18:31:16 -0700 Subject: [PATCH] mm/mempolicy.c: check parameters first in kernel_get_mempolicy Previous implementatoin calls untagged_addr() before error check, while if the error check failed and return EINVAL, the untagged_addr() call is just useless work. Signed-off-by: Wenchao Hao Signed-off-by: Andrew Morton Reviewed-by: Andrew Morton Link: http://lkml.kernel.org/r/20200801090825.5597-1-haowenchao22@gmail.com Signed-off-by: Linus Torvalds --- mm/mempolicy.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 92030ead2506..25b7e412c20b 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1632,11 +1632,11 @@ static int kernel_get_mempolicy(int __user *policy, int pval; nodemask_t nodes; - addr = untagged_addr(addr); - if (nmask != NULL && maxnode < nr_node_ids) return -EINVAL; + addr = untagged_addr(addr); + err = do_get_mempolicy(&pval, &nodes, addr, flags); if (err)