From 3477af70262872cca2dc78c7a8004dec321d8ca4 Mon Sep 17 00:00:00 2001 From: Sabrina Dubroca Date: Tue, 14 Oct 2025 11:17:00 +0200 Subject: [PATCH] tls: don't rely on tx_work during send() [ Upstream commit 7f846c65ca11e63d2409868ff039081f80e42ae4 ] With async crypto, we rely on tx_work to actually transmit records once encryption completes. But while send() is running, both the tx_lock and socket lock are held, so tx_work_handler cannot process the queue of encrypted records, and simply reschedules itself. During a large send(), this could last a long time, and use a lot of memory. Transmit any pending encrypted records before restarting the main loop of tls_sw_sendmsg_locked. Fixes: a42055e8d2c3 ("net/tls: Add support for async encryption of records for performance") Reported-by: Jann Horn Signed-off-by: Sabrina Dubroca Link: https://patch.msgid.link/8396631478f70454b44afb98352237d33f48d34d.1760432043.git.sd@queasysnail.net Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- 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 8dabbbf52168..b175f0595a47 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -1052,6 +1052,13 @@ alloc_encrypted: else if (ret != -EAGAIN) goto send_end; } + + /* Transmit if any encryptions have completed */ + if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { + cancel_delayed_work(&ctx->tx_work.work); + tls_tx_records(sk, msg->msg_flags); + } + continue; rollback_iter: copied -= try_to_copy; @@ -1106,6 +1113,12 @@ fallback_to_reg_send: goto send_end; } } + + /* Transmit if any encryptions have completed */ + if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { + cancel_delayed_work(&ctx->tx_work.work); + tls_tx_records(sk, msg->msg_flags); + } } continue;