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 ACA5135AC20 for ; Sat, 28 Feb 2026 18:19:31 +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=1772302771; cv=none; b=TuPHPhw63omcCn5RgFZRa6AsWIwGdGJQvvw5WtEld6kG2hiy/GqlT6IUi7njPdZlN6idgkVcXKg2mPanUK9qWVKRgCPW0nwO8A5hXCGcC+ZMOAn698OGiGdYtjycVRftST6nt6EBtj+v8VrEE2DXl7X9Afw3YwIVQwsZbErCtqU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302771; c=relaxed/simple; bh=81un091ESFW314h6JIVdv1wNKzq4YbRrXXMmAS0sFU4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oRm9D3IiL/DPFIBOZ8qSdwi3Mb3pGYZDhB1E4ywywPt56rfSW0VtPBkfRTzlptgaOKMFFjykO7vyeOqbVyWyI/aUOInlsBonih78JSxxjoyF5z/FKd7WtP50oA0Q1RvF+5Mb3vDct2nubCId5jiDXq6IXCPoJtFt948rMbrtj6U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RZMTEM1z; 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="RZMTEM1z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E8CD1C2BCF5; Sat, 28 Feb 2026 18:19:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302771; bh=81un091ESFW314h6JIVdv1wNKzq4YbRrXXMmAS0sFU4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RZMTEM1zaHVnPm2kTXciJHtJc070rjOMFXQTvI+PkrdmZvwL0g2OQFPyKqWHEkbCa guh9pmLEFUkp9ikCB9RNvsiaDxYCEEB7qrunY5yYX9ZeUFVf09IvcTEu93RvLdZsvu mKo1mDHTD8OlFlRzgqehoL/7eaHWwGCYSREvjKrR2E4Pl6q0wZanOAFh3gp76QckKD pXs37YLIfbP90u+ba/gvqwPPDa6ejqKgVj0/oBlBmlooz79saMp9lmkL6D12I+eacc R8HxHHnttkvNTxPeu8E8YAHwYqkuIVY3XdVc6uga/ma2NMfLrLv9uzs5kd2NmHXZVC 0UztpiJ5UgnUw== From: Sasha Levin To: patches@lists.linux.dev Cc: Eric Dumazet , Simon Horman , Fernando Fernandez Mancera , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.10 144/147] ipv6: fix a race in ip6_sock_set_v6only() Date: Sat, 28 Feb 2026 13:17:32 -0500 Message-ID: <20260228181736.1605592-144-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228181736.1605592-1-sashal@kernel.org> References: <20260228181736.1605592-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Eric Dumazet [ Upstream commit 452a3eee22c57a5786ae6db5c97f3b0ec13bb3b7 ] It is unlikely that this function will be ever called with isk->inet_num being not zero. Perform the check on isk->inet_num inside the locked section for complete safety. Fixes: 9b115749acb24 ("ipv6: add ip6_sock_set_v6only") Signed-off-by: Eric Dumazet Reviewed-by: Simon Horman Reviewed-by: Fernando Fernandez Mancera Link: https://patch.msgid.link/20260216102202.3343588-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- include/net/ipv6.h | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 2909233427de0..d7b0710d0d9c1 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -1177,12 +1177,15 @@ int ipv6_sock_mc_drop(struct sock *sk, int ifindex, static inline int ip6_sock_set_v6only(struct sock *sk) { - if (inet_sk(sk)->inet_num) - return -EINVAL; + int ret = 0; + lock_sock(sk); - sk->sk_ipv6only = true; + if (inet_sk(sk)->inet_num) + ret = -EINVAL; + else + sk->sk_ipv6only = true; release_sock(sk); - return 0; + return ret; } static inline void ip6_sock_set_recverr(struct sock *sk) -- 2.51.0