From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 775DF1EB5DD; Wed, 7 May 2025 19:08:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746644920; cv=none; b=SsXfhKqM3/qYE+wh9tjIJq97VEUlM8BU/2vbqS1bkkwmVSnakcC9uBp8XFjG1xgRdcun36FQAKq2LBHSSZ9fxAbzeXo6Md8FiuvFnjWbK/7T5NTsR5MPITfImXw23eG55YutnsHbaofKm+xEwQ0E+tYWYVNR2zYsvQ1TxU3Fq2w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746644920; c=relaxed/simple; bh=9KSSKpSVTTaSpzc4gpqZR61Tnt5plZekX/L0nIJ7QgM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Qc+Up1aIHbqkXiebKG2XP+mRiCgmkUueLorKE1UGoa/zq3wOhY4P2cWXebNYgBnJATE4HVoAgr9FkJgTIqyQzLSs4PqXaL0TZze9vnpcOpd5sFx3BJeGXpJxDLknjH6z9v76mUjjPSWQn9M5nznG3HI1y5z1juMZ2sMTgDqQ0Vc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=TrFg3Gtd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="TrFg3Gtd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DBEB1C4CEE2; Wed, 7 May 2025 19:08:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1746644920; bh=9KSSKpSVTTaSpzc4gpqZR61Tnt5plZekX/L0nIJ7QgM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TrFg3GtdGvtLjr80O901vl+jcLZSk+dmDYDS0pHyDDELX9fMUSxVh9Lt+kXfgF4Ud jruXo6SagibUQEhl2afHf1X55Xy4FJepf+EYmLoM1uaJoF/kTdnOzr1smyv0OJYz2q iC3ox35tObxj6sLjhV0F0EMPHQVnE13PLgDMKAhk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Nick Zavaritsky , Eduard Zingerman , Alexei Starovoitov , Shung-Hsi Yu Subject: [PATCH 6.6 036/129] selftests/bpf: test for changing packet data from global functions Date: Wed, 7 May 2025 20:39:32 +0200 Message-ID: <20250507183814.998795348@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250507183813.500572371@linuxfoundation.org> References: <20250507183813.500572371@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eduard Zingerman commit 3f23ee5590d9605dbde9a5e1d4b97637a4803329 upstream. Check if verifier is aware of packet pointers invalidation done in global functions. Based on a test shared by Nick Zavaritsky in [0]. [0] https://lore.kernel.org/bpf/0498CA22-5779-4767-9C0C-A9515CEA711F@gmail.com/ Suggested-by: Nick Zavaritsky Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/r/20241210041100.1898468-5-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov Signed-off-by: Shung-Hsi Yu Signed-off-by: Greg Kroah-Hartman --- tools/testing/selftests/bpf/progs/verifier_sock.c | 28 ++++++++++++++++++++++ 1 file changed, 28 insertions(+) --- a/tools/testing/selftests/bpf/progs/verifier_sock.c +++ b/tools/testing/selftests/bpf/progs/verifier_sock.c @@ -977,4 +977,32 @@ l1_%=: r0 = *(u8*)(r7 + 0); \ : __clobber_all); } +__noinline +long skb_pull_data2(struct __sk_buff *sk, __u32 len) +{ + return bpf_skb_pull_data(sk, len); +} + +__noinline +long skb_pull_data1(struct __sk_buff *sk, __u32 len) +{ + return skb_pull_data2(sk, len); +} + +/* global function calls bpf_skb_pull_data(), which invalidates packet + * pointers established before global function call. + */ +SEC("tc") +__failure __msg("invalid mem access") +int invalidate_pkt_pointers_from_global_func(struct __sk_buff *sk) +{ + int *p = (void *)(long)sk->data; + + if ((void *)(p + 1) > (void *)(long)sk->data_end) + return TCX_DROP; + skb_pull_data1(sk, 0); + *p = 42; /* this is unsafe */ + return TCX_PASS; +} + char _license[] SEC("license") = "GPL";