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 7AA312BE7B8; Tue, 11 Nov 2025 01:29:16 +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=1762824556; cv=none; b=ICC7XyZYv2KE9L4ddRyNrxT78/EaxROnUVIgCd2gu7NiYrWKIzXB7I25QLYbmg8wga9zB6tcCteOzWwS3nvA3aGZOFIg/Ok9Axr7l2lcDK187fltgTT4+NGWdAykyO+k++YSOwUE15aMNmIyKZ7Qb/jhi1N14GBDzLCJSRZ+I/Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762824556; c=relaxed/simple; bh=ATNOZwyJ5D25yPtGLg4KcnLuWADrxhQl08ukv0kzR8o=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cIO6h4CAc8SCtoKK4IN6pU9sD+VtNightUJmNT6GbDbzbkBRMiHPs68Zbiv2CVC2lvrUsyWa7O+cmdXDPNBxd4FcqHvU2yymjO8ZckSW7BXY0Bv4zfCsgDNsLNjknKcdJq6IBMdQkuxB3TzzXk8ZgzpzzjlUL//yfMvDjYxfjeM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=00KXPD8m; 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="00KXPD8m" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 184E9C19421; Tue, 11 Nov 2025 01:29:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1762824556; bh=ATNOZwyJ5D25yPtGLg4KcnLuWADrxhQl08ukv0kzR8o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=00KXPD8mH19/3DNTe0yKzrKU0VTaYe8X29Wfysv5QFnEtlTB42JwEaOHKafUVFvqP HloWDCyklTZ5Nuii5jyWrrsCU1N8P4xBhzTLbgG6/bKMQAWzslY8mD9FoZ4lxHxTXU dhgnNvmlTpLLcMfaiEebjmvieF3VtGQRAP9RCUQw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, David Ahern , Mina Almasry , Eric Dumazet , Stanislav Fomichev , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.17 523/849] net: devmem: expose tcp_recvmsg_locked errors Date: Tue, 11 Nov 2025 09:41:33 +0900 Message-ID: <20251111004549.067210126@linuxfoundation.org> X-Mailer: git-send-email 2.51.2 In-Reply-To: <20251111004536.460310036@linuxfoundation.org> References: <20251111004536.460310036@linuxfoundation.org> User-Agent: quilt/0.69 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 6.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stanislav Fomichev [ Upstream commit 18282100d7040614b553f1cad737cb689c04e2b9 ] tcp_recvmsg_dmabuf can export the following errors: - EFAULT when linear copy fails - ETOOSMALL when cmsg put fails - ENODEV if one of the frags is readable - ENOMEM on xarray failures But they are all ignored and replaced by EFAULT in the caller (tcp_recvmsg_locked). Expose real error to the userspace to add more transparency on what specifically fails. In non-devmem case (skb_copy_datagram_msg) doing `if (!copied) copied=-EFAULT` is ok because skb_copy_datagram_msg can return only EFAULT. Reviewed-by: David Ahern Reviewed-by: Mina Almasry Reviewed-by: Eric Dumazet Signed-off-by: Stanislav Fomichev Link: https://patch.msgid.link/20250910162429.4127997-1-sdf@fomichev.me Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/ipv4/tcp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index ba36f558f144c..f421cad69d8c9 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2821,9 +2821,9 @@ static int tcp_recvmsg_locked(struct sock *sk, struct msghdr *msg, size_t len, err = tcp_recvmsg_dmabuf(sk, skb, offset, msg, used); - if (err <= 0) { + if (err < 0) { if (!copied) - copied = -EFAULT; + copied = err; break; } -- 2.51.0