From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=206.220.120.4 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794527995; b=4x8eW6jIytIa1LLcAWWfkjLUbWkDjLTLi51SjV70iOqph83m/hgRNwOGcS/1UBmkU/US 5zB2dTJuCJLbJTzXFT+4s8EKRKP+5yy132IYuRcKf5+fSzmjyoDNiqCYWqx8bnR+A1jWr eAqp2KGTW/KJ6FJfXjwErHGM8RAwLeWmzq3Qv1ujj3fC79M2GKR/2myHcA26Oh06wmXsY SbkrD5qj+2axVcclO8IuKfcVZzlAyt1dmbuGURGFOQKunWohU3v7tO9CdnOPhaz6IULMY Q/mclw58b2Zr8aoHslH7nJ4BiXuV3B2iVvV7HwaxweOvtIFoZ0zMUlovIGSQec+8BFg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794527995; h=DMARC-Filter:Received:DKIM-Signature:From:To:Cc:Subject:Date: Message-ID:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding; bh=qv63BJZJpTuqn9oT/kkgXxBPtvhk9LgkyaQuITas9nE=; b=396Ne7mwDkxxFJog55rzv7YkHoWGZoLAOQEhIb6p14Qh29xzR9M9rBOPtfbazVbW9eMj vf4J+xb7kv+5B03Ubgcxx/75TVxIZZNVXephzZwT+D++apEM+W2NjKPqQjvWFyYgB6UAl Swm8zF750ESlvirRe0a24T37pnphPCxypP4ckKGxcz5gQjXXUvY6vj3YKLtBsJmXuuXwg vOxmuV3osT2KG72XehGbmFD4o9ME3U6qDgLDSLB2RNYAyMJCroFMTrbiD4sXA9n5dFgeQ TzO8RwtLuyJsPLUhsAfD4mAJ/4N8q6eKsEmuwYwW5u++cq8qj7BK2X68OA0pwv/N1ew== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=grapheneos.org; spf=pass smtp.mailfrom=grapheneos.org; dkim=pass header.d=grapheneos.org header.i=@grapheneos.org header.a=rsa-sha256 header.s=default header.b=Dz9FIiUP; arc=none smtp.remote-ip=206.220.120.4 Received: from mail.grapheneos.org (mail.grapheneos.org [206.220.120.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9B5E9606A327; Thu, 12 Nov 2026 23:59:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 9B5E9606A327 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=grapheneos.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=grapheneos.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=grapheneos.org header.i=@grapheneos.org header.a=rsa-sha256 header.s=default header.b=Dz9FIiUP Received: by mail.grapheneos.org (Postfix) id 5F1D23C08EE90; Thu, 12 Nov 2026 23:59:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=grapheneos.org; s=default; t=1794527994; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=qv63BJZJpTuqn9oT/kkgXxBPtvhk9LgkyaQuITas9nE=; b=Dz9FIiUP20f/k1yraDdTBqh6VRj7eFvi6Pb4XjJSWztaEAW3O81rZmC8RPBxGCCCxkhzvN 2H5JNvbM5xyIbZzhZFlO1MotD7njvO947CSaFR+jDgO1J3yrSdA+Se1zHXFpW+BHT9nODw 2Lpa+qGJSpVtqWJg8mZFP3EejsOZ00kP+UpQGxpoTJR70EEv6I7gxftmaISMdtQaBS9DfE KuhF3vqbFTXWtC8LKtXU70DmbbhlvyQpVmlkRm+1bJ3YWGyGsI0c8Wg90MQ9yQlN0T9TFr b36SvQHGLRMaqhD4HdaqVPoR3dTlSGuPwVaZhaWG98dvOYf69Bm/ZKoDiYgaGQ== From: liamsmith827 To: netdev@vger.kernel.org Cc: David Ahern , Ido Schimmel , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Shuah Khan , linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Liam Smith Subject: [PATCH net-next v3 1/4] ipv4: add FIB_LOOKUP_REPORT_MISS Date: Thu, 12 Nov 2026 23:59:29 +0000 Message-ID: <20261112235932.23836-2-liamsmith827@grapheneos.org> In-Reply-To: <20261112235932.23836-1-liamsmith827@grapheneos.org> References: <20261112235932.23836-1-liamsmith827@grapheneos.org> X-Mailing-List: netdev@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Liam Smith Currently, fib_lookup() returns -ENETUNREACH for both a routing lookup miss and an unreachable rule. These two cases must be distinguishable to facilitate a fallback that only occurs when there's a miss. Add a new FIB_LOOKUP flag that instructs lookups to return -ESRCH when there's a miss. Signed-off-by: Liam Smith --- include/net/fib_rules.h | 1 + include/net/ip_fib.h | 6 +++--- net/ipv4/fib_rules.c | 2 +- 3 files changed, 5 insertions(+), 4 deletions(-) diff --git a/include/net/fib_rules.h b/include/net/fib_rules.h index c6b94790fa81..df1cb39ddf92 100644 --- a/include/net/fib_rules.h +++ b/include/net/fib_rules.h @@ -59,6 +59,7 @@ struct fib_lookup_arg { int flags; #define FIB_LOOKUP_NOREF 1 #define FIB_LOOKUP_IGNORE_LINKSTATE 2 +#define FIB_LOOKUP_REPORT_MISS 4 }; struct fib_rules_ops { diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index 92f4eb8b86d7..d0b4f261585a 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -318,7 +318,7 @@ static inline int fib_lookup(struct net *net, const struct flowi4 *flp, struct fib_result *res, unsigned int flags) { struct fib_table *tb; - int err = -ENETUNREACH; + int err = -EAGAIN; rcu_read_lock(); @@ -327,7 +327,7 @@ static inline int fib_lookup(struct net *net, const struct flowi4 *flp, err = fib_table_lookup(tb, flp, res, flags | FIB_LOOKUP_NOREF); if (err == -EAGAIN) - err = -ENETUNREACH; + err = (flags & FIB_LOOKUP_REPORT_MISS) ? -ESRCH : -ENETUNREACH; rcu_read_unlock(); @@ -398,7 +398,7 @@ static inline int fib_lookup(struct net *net, struct flowi4 *flp, err = fib_table_lookup(tb, flp, res, flags); if (err == -EAGAIN) - err = -ENETUNREACH; + err = (flags & FIB_LOOKUP_REPORT_MISS) ? -ESRCH : -ENETUNREACH; out: rcu_read_unlock(); diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c index 060501b376a8..3d7dcb8d0865 100644 --- a/net/ipv4/fib_rules.c +++ b/net/ipv4/fib_rules.c @@ -101,7 +101,7 @@ int __fib_lookup(struct net *net, struct flowi4 *flp, res->tclassid = 0; #endif - if (err == -ESRCH) + if (err == -ESRCH && !(flags & FIB_LOOKUP_REPORT_MISS)) err = -ENETUNREACH; return err; -- 2.47.3