From: Jiayuan Chen <jiayuan.chen@linux.dev> stable inclusion from stable-v6.6.102 commit 0e853c1464bcf61207f8b5c32d2ac5ee495e859d category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/13525 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 178f6a5c8cb3b6be1602de0964cd440243f493c9 ] When sending plaintext data, we initially calculated the corresponding ciphertext length. However, if we later reduced the plaintext data length via socket policy, we failed to recalculate the ciphertext length. This results in transmitting buffers containing uninitialized data during ciphertext transmission. This causes uninitialized bytes to be appended after a complete "Application Data" packet, leading to errors on the receiving end when parsing TLS record. Fixes: d3b18ad31f93 ("tls: add bpf support to sk_msg handling") Reported-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Jakub Kicinski <kuba@kernel.org> Link: https://lore.kernel.org/bpf/20250609020910.397930-2-jiayuan.chen@linux.dev Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Dong Chenchen <dongchenchen2@huawei.com> --- net/tls/tls_sw.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index b28e87371fa1..d1cf3a12cf67 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -872,6 +872,19 @@ static int bpf_exec_tx_verdict(struct sk_msg *msg, struct sock *sk, delta = msg->sg.size; psock->eval = sk_psock_msg_verdict(sk, psock, msg); delta -= msg->sg.size; + + if ((s32)delta > 0) { + /* It indicates that we executed bpf_msg_pop_data(), + * causing the plaintext data size to decrease. + * Therefore the encrypted data size also needs to + * correspondingly decrease. We only need to subtract + * delta to calculate the new ciphertext length since + * ktls does not support block encryption. + */ + struct sk_msg *enc = &ctx->open_rec->msg_encrypted; + + sk_msg_trim(sk, enc, enc->sg.size - delta); + } } if (msg->cork_bytes && msg->cork_bytes > msg->sg.size && !enospc && !full_record) { -- 2.25.1