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 1D54344BCB0; Wed, 29 Apr 2026 22:30:07 +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=1777501807; cv=none; b=LvFQn8TYlYSZah0caETltJLbSSQXWO87uI3ZO5eiRmoeaLiIz93z/FxMPQdWQaiH/QtWzK7zP/yZcaNbo3/US4u5PJwmsW/VN9tWt4inmw04ATyuL542cB32rwFn0o/0kxIMiLDfKEw4K436hhaP3G2yoiSXOxt/Xt2lO0NCtuY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777501807; c=relaxed/simple; bh=iVcfrFHyVFACKF5GUNHFqaW6IcL9IiKuD0iIuXq+xLs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=c8aBPR0FYpx5C1G+OzeKFBE9+MLElPmvOtG/1ZAjwksbuEgaVRtjEKWZToD23pc8WKRSAmxvT7WGSpDM0MegATPj50+Qi/LAV+0+aCvAEo+IKmMZMtXxbUsRxqAXLqxOVRI2tlfd0K1GZLqcih+qM7WHDITgEvhDj91ldcs7CXU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=FcAnItEy; 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="FcAnItEy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5E948C2BCB4; Wed, 29 Apr 2026 22:30:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777501806; bh=iVcfrFHyVFACKF5GUNHFqaW6IcL9IiKuD0iIuXq+xLs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FcAnItEyn/KmqHPYRrEZL22rO1Lrv3CvmMve22n3LdZ3vF6nLxCmCSAmFr74JB42v aLNAXaYNrqg8/zhYnwpzQGgYyB8UmzyCS8qhV5CjVWq3Xz10CTM8WptW0OVGMCZSDC 7hWS4TE5XbKZjda5wbCe74mpku7u3DURaFv3dj5L7SnjJX2au9BCus0mSTtCG8OpB3 rEb3Je76U+4vRekU3x3CurDVmDsdYyFQMlqqRiWffmsEcd/GPdE8qpEIay4NKWOxFh zuB3deizKCzGtZU/rc0MIu3zZkToNW6i6KczqZMqmq22BACsvcF1JX9RJKeRldLOn2 BBYCbG0EaV52A== From: Jakub Kicinski To: davem@davemloft.net Cc: netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com, andrew+netdev@lunn.ch, horms@kernel.org, bpf@vger.kernel.org, john.fastabend@gmail.com, sd@queasysnail.net, linux-kselftest@vger.kernel.org, Jakub Kicinski , Alessandro G , jiayuan.chen@linux.dev, ast@kernel.org Subject: [PATCH net 6/7] net: tls: fix use-after-free in tls_sw_sendmsg_locked after bpf verdict Date: Wed, 29 Apr 2026 15:29:43 -0700 Message-ID: <20260429222944.2139041-7-kuba@kernel.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260429222944.2139041-1-kuba@kernel.org> References: <20260429222944.2139041-1-kuba@kernel.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit After bpf_exec_tx_verdict() returns in the zerocopy path, the local msg_pl/msg_en pointers may be stale. If a BPF program set apply_bytes such that tls_push_record() splits the open record via tls_split_open_record(), ctx->open_rec is replaced with the split remainder while the original record is pushed to the tx_list and may be freed by tls_tx_records(). The caller's cached msg_pl/msg_en still reference the old (now-freed) record. This is triggered when bpf_exec_tx_verdict() returns -ENOSPC (BPF set cork_bytes > remaining data) after an internal record split: the code dereferences msg_pl->cork_bytes on the freed record, causing a UAF. Reported-by: Alessandro G Fixes: 54a3ecaeeeae ("bpf: fix ktls panic with sockmap") Signed-off-by: Jakub Kicinski --- CC: john.fastabend@gmail.com CC: sd@queasysnail.net CC: jiayuan.chen@linux.dev CC: ast@kernel.org CC: bpf@vger.kernel.org --- net/tls/tls_sw.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 600e13effaab..d086b43fc675 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -1157,6 +1157,13 @@ static int tls_sw_sendmsg_locked(struct sock *sk, struct msghdr *msg, else if (ret == -ENOMEM) goto wait_for_memory; else if (ctx->open_rec && ret == -ENOSPC) { + /* bpf_exec_tx_verdict() may have + * called tls_split_open_record(), + * freeing the old record. Re-fetch. + */ + rec = ctx->open_rec; + msg_pl = &rec->msg_plaintext; + msg_en = &rec->msg_encrypted; if (msg_pl->cork_bytes) { ret = 0; goto send_end; -- 2.54.0