From: Roman Gushchin <roman.gushchin@linux.dev>
Date: Thu, 2 Jun 2022 00:56:22 +0000 (-0700)
Subject: mm-shrinkers-add-scan-interface-for-shrinker-debugfs-fix
X-Git-Tag: maple_v12_fixes~154
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=4c57927ad92f229e578d94dbf8ecebd23c356fa0;p=users%2Fjedix%2Flinux-maple.git

mm-shrinkers-add-scan-interface-for-shrinker-debugfs-fix

improve typing, fix arg count checking

Link: https://lkml.kernel.org/r/YpgKttTowT22mKPQ@carbon
Signed-off-by: Roman Gushchin <roman.gushchin@linux.dev>
Acked-by: Muchun Song <songmuchun@bytedance.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/mm/shrinker_debug.c b/mm/shrinker_debug.c
index e25114e0c41cb..12026472daaec 100644
--- a/mm/shrinker_debug.c
+++ b/mm/shrinker_debug.c
@@ -110,21 +110,21 @@ static ssize_t shrinker_debugfs_scan_write(struct file *file,
 					   size_t size, loff_t *pos)
 {
 	struct shrinker *shrinker = file->private_data;
-	unsigned long nr_to_scan = 0, ino;
+	unsigned long nr_to_scan = 0, ino, read_len;
 	struct shrink_control sc = {
 		.gfp_mask = GFP_KERNEL,
 	};
 	struct mem_cgroup *memcg = NULL;
 	int nid;
 	char kbuf[72];
-	int read_len = size < (sizeof(kbuf) - 1) ? size : (sizeof(kbuf) - 1);
 	ssize_t ret;
 
+	read_len = size < (sizeof(kbuf) - 1) ? size : (sizeof(kbuf) - 1);
 	if (copy_from_user(kbuf, buf, read_len))
 		return -EFAULT;
 	kbuf[read_len] = '\0';
 
-	if (sscanf(kbuf, "%lu %d %lu", &ino, &nid, &nr_to_scan) < 2)
+	if (sscanf(kbuf, "%lu %d %lu", &ino, &nid, &nr_to_scan) != 2)
 		return -EINVAL;
 
 	if (nid < 0 || nid >= nr_node_ids)