diff mbox series

[019/165] mm/mempolicy.c: check parameters first in kernel_get_mempolicy

Message ID 20200812013116.Bl2q7CRRo%akpm@linux-foundation.org (mailing list archive)
State New, archived
Headers show
Series [001/165] percpu: return number of released bytes from pcpu_free_area() | expand

Commit Message

Andrew Morton Aug. 12, 2020, 1:31 a.m. UTC 
From: Wenchao Hao <haowenchao22@gmail.com>
Subject: 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.

Link: http://lkml.kernel.org/r/20200801090825.5597-1-haowenchao22@gmail.com
Signed-off-by: Wenchao Hao <haowenchao22@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/mempolicy.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox series

Patch

--- a/mm/mempolicy.c~mm-mempolicy-check-parameters-first-in-kernel_get_mempolicy
+++ a/mm/mempolicy.c
@@ -1632,11 +1632,11 @@  static int kernel_get_mempolicy(int __us
 	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)