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 C4F083419D for ; Mon, 9 Oct 2023 13:52:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="P+i0b08e" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3DAC3C433C8; Mon, 9 Oct 2023 13:52:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1696859579; bh=Ea/Q146n3WDinjUjPWuwaOUeg2wR4ALlpr7u5zE162M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=P+i0b08ehj6KyNNSIiRhk5sC8RYcVyRd1gi+BuXodOeQWvQFCDwg1yMrhyIUW9jKm mNpEXXrBzcUap8e4pSIB1dlew3w0GgQ60ehuoLVvoANeP7puIm3qtlUejDj3r8yHHj VAL2VNE9PLSgYjgIYzqICdsmXW/X/Br+GjpPrIzA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Daniel Borkmann , Stanislav Fomichev , Sasha Levin Subject: [PATCH 4.19 39/91] bpf: Clarify error expectations from bpf_clone_redirect Date: Mon, 9 Oct 2023 15:06:11 +0200 Message-ID: <20231009130112.878726875@linuxfoundation.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231009130111.518916887@linuxfoundation.org> References: <20231009130111.518916887@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stanislav Fomichev [ Upstream commit 7cb779a6867fea00b4209bcf6de2f178a743247d ] Commit 151e887d8ff9 ("veth: Fixing transmit return status for dropped packets") exposed the fact that bpf_clone_redirect is capable of returning raw NET_XMIT_XXX return codes. This is in the conflict with its UAPI doc which says the following: "0 on success, or a negative error in case of failure." Update the UAPI to reflect the fact that bpf_clone_redirect can return positive error numbers, but don't explicitly define their meaning. Reported-by: Daniel Borkmann Signed-off-by: Stanislav Fomichev Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20230911194731.286342-1-sdf@google.com Signed-off-by: Sasha Levin --- include/uapi/linux/bpf.h | 4 +++- tools/include/uapi/linux/bpf.h | 4 +++- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 6334aede67fc2..91c43f3756123 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -693,7 +693,9 @@ union bpf_attr { * performed again, if the helper is used in combination with * direct packet access. * Return - * 0 on success, or a negative error in case of failure. + * 0 on success, or a negative error in case of failure. Positive + * error indicates a potential drop or congestion in the target + * device. The particular positive error codes are not defined. * * u64 bpf_get_current_pid_tgid(void) * Return diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 0c30ab898e2a5..37259bae15010 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -691,7 +691,9 @@ union bpf_attr { * performed again, if the helper is used in combination with * direct packet access. * Return - * 0 on success, or a negative error in case of failure. + * 0 on success, or a negative error in case of failure. Positive + * error indicates a potential drop or congestion in the target + * device. The particular positive error codes are not defined. * * u64 bpf_get_current_pid_tgid(void) * Return -- 2.40.1