Subject: [PATCH net-next] net/dns_resolver: consolidate namelen checks in dns_query

From: Thorsten Blum <[email-masked]>
Date: Mon, 25 May 2026 11:54:01 +0200

Consolidate the namelen checks and return -EINVAL early if needed. Drop
the namelen == 0 check since it is covered by namelen < 3.

Signed-off-by: Thorsten Blum <[email-masked]>
---
 net/dns_resolver/dns_query.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/net/dns_resolver/dns_query.c b/net/dns_resolver/dns_query.c
index e1c09d7b8200..c250d82cad96 100644
--- a/net/dns_resolver/dns_query.c
+++ b/net/dns_resolver/dns_query.c
@@ -73,7 +73,7 @@ int dns_query(struct net *net,
 	kenter("%s,%*.*s,%zu,%s",
 	       type, (int)namelen, (int)namelen, name, namelen, options);
 
-	if (!name || namelen == 0)
+	if (!name || namelen < 3 || namelen > 255)
 		return -EINVAL;
 
 	/* construct the query key description as "[<type>:]<name>" */
@@ -86,8 +86,6 @@ int dns_query(struct net *net,
 		desclen += typelen + 1;
 	}
 
-	if (namelen < 3 || namelen > 255)
-		return -EINVAL;
 	desclen += namelen + 1;
 
 	desc = kmalloc(desclen, GFP_KERNEL);