From nobody Sat Oct 4 11:10:11 2025 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 EAC972E22BF; Mon, 18 Aug 2025 18:04:07 +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=1755540248; cv=none; b=mRduGjHhUYYegWIalUFsha7jb28beZixipxB0OqogZvdiSE0U++KpiTo/IBdxVBxJfwHyrGzsMyjEpoDUNOMy8164Amj3hywuHRZAPxnc0tbtAzq7GSuK51sVqhvNfDVwchXj38i4Fe0RoXJvn8fFyJ+VGghG0LkahZQ1T3LlQc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755540248; c=relaxed/simple; bh=Xp4CQi1oRWwYMH5i+mF7dz/szvq22cKIqd3crJYwonU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=EIrzdxew7Ccq7BZx6HqPnzkg/VwubZuSWUExGHZrCDHPJRUZbKpcHa4IrpJ8eE4snKULj/FFwE56xaIuoWttH3iS6eN4N6iv1SIgMDlaQyqvSMSLSPDUGuQYoMTkM9+9cxmaLXdBDHrUypHF7lICEHsg4Lv0wQM+7CLYQWEpn6M= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gkn5ybC9; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gkn5ybC9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CED2DC4CEF1; Mon, 18 Aug 2025 18:04:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755540247; bh=Xp4CQi1oRWwYMH5i+mF7dz/szvq22cKIqd3crJYwonU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gkn5ybC9UDbyACYdSpNvRWXbAtBXwutWhD79E1Z65QmOZ5awuywoYvBwKq8kDUM3w YbMZaNWtSEpTAuvt1LeEVPE4BFTOAdIwAujdeitiREUZiAiW2920rECdWJd/K6J9Rs ZdjuKW3+N8K3EhPGF5dk/KcGPA7LwgmYKrBOCnNsZj1cVTrrrCBupIGL2qPCO8rAsk 7KE9MuDnDNkm93NniXMJhHv45tGcDx92G9Pnr8UAxbbYSLSoRd7eLQCYKIbNkLN5dI 1kXwI4M63cHOF0syO3s6ahR13HtH5te+H/1yVZGynoOGjLTd5CKDDvaty3n0Sen8Tj 0OkqXOXg+UYmQ== From: Will Deacon To: linux-kernel@vger.kernel.org Cc: virtualization@lists.linux.dev, netdev@vger.kernel.org, Will Deacon , Alexander Viro , Christian Brauner , "David S. Miller" , Eric Dumazet , Hillf Danton , Jakub Kicinski , Jason Wang , "Michael S. Tsirkin" , Paolo Abeni , Stefan Hajnoczi , Stefano Garzarella Subject: [PATCH 1/2] net: Introduce skb_copy_datagram_from_iter_full() Date: Mon, 18 Aug 2025 19:03:54 +0100 Message-Id: <20250818180355.29275-2-will@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250818180355.29275-1-will@kernel.org> References: <20250818180355.29275-1-will@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" In a similar manner to copy_from_iter()/copy_from_iter_full(), introduce skb_copy_datagram_from_iter_full() which reverts the iterator to its initial state when returning an error. A subsequent fix for a vsock regression will make use of this new function. Cc: Paolo Abeni Cc: Christian Brauner Cc: Eric Dumazet Cc: Jakub Kicinski Cc: "David S. Miller" Cc: Alexander Viro Signed-off-by: Will Deacon --- include/linux/skbuff.h | 2 ++ net/core/datagram.c | 14 ++++++++++++++ 2 files changed, 16 insertions(+) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 14b923ddb6df..fa633657e4c0 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -4172,6 +4172,8 @@ int skb_copy_and_crc32c_datagram_iter(const struct sk= _buff *skb, int offset, struct iov_iter *to, int len, u32 *crcp); int skb_copy_datagram_from_iter(struct sk_buff *skb, int offset, struct iov_iter *from, int len); +int skb_copy_datagram_from_iter_full(struct sk_buff *skb, int offset, + struct iov_iter *from, int len); int zerocopy_sg_from_iter(struct sk_buff *skb, struct iov_iter *frm); void skb_free_datagram(struct sock *sk, struct sk_buff *skb); int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int f= lags); diff --git a/net/core/datagram.c b/net/core/datagram.c index 94cc4705e91d..f474b9b120f9 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -618,6 +618,20 @@ int skb_copy_datagram_from_iter(struct sk_buff *skb, i= nt offset, } EXPORT_SYMBOL(skb_copy_datagram_from_iter); =20 +int skb_copy_datagram_from_iter_full(struct sk_buff *skb, int offset, + struct iov_iter *from, int len) +{ + struct iov_iter_state state; + int ret; + + iov_iter_save_state(from, &state); + ret =3D skb_copy_datagram_from_iter(skb, offset, from, len); + if (ret) + iov_iter_restore(from, &state); + return ret; +} +EXPORT_SYMBOL(skb_copy_datagram_from_iter_full); + int zerocopy_fill_skb_from_iter(struct sk_buff *skb, struct iov_iter *from, size_t length) { --=20 2.51.0.rc1.167.g924127e9c0-goog