From: Jakub Kicinski <kuba@kernel.org>
Date: Tue, 6 Feb 2024 17:18:20 -0800
Subject: tls: fix race between tx work scheduling and socket close
Patch-mainline: v6.8-rc5
Git-commit: e01e3934a1b2d122919f73bc6ddbe1cdafc4bbdb
References: CVE-2024-26585 bsc#1220187
Similarly to previous commit, the submitting thread (recvmsg/sendmsg)
may exit as soon as the async crypto handler calls complete().
Reorder scheduling the work before calling complete().
This seems more logical in the first place, as it's
the inverse order of what the submitting thread will do.
Reported-by: valis <sec@valis.email>
Fixes: a42055e8d2c3 ("net/tls: Add support for async encryption of records for performance")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Michal Kubecek <mkubecek@suse.cz>
---
net/tls/tls_sw.c | 16 ++++++----------
1 file changed, 6 insertions(+), 10 deletions(-)
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -380,7 +380,6 @@ static void tls_encrypt_done(struct crypto_async_request *req, int err)
struct scatterlist *sge;
struct sk_msg *msg_en;
struct tls_rec *rec;
- bool ready = false;
int pending;
rec = container_of(aead_req, struct tls_rec, aead_req);
@@ -412,21 +411,18 @@ static void tls_encrypt_done(struct crypto_async_request *req, int err)
/* If received record is at head of tx_list, schedule tx */
first_rec = list_first_entry(&ctx->tx_list,
struct tls_rec, list);
- if (rec == first_rec)
- ready = true;
+ if (rec == first_rec) {
+ /* Schedule the transmission */
+ if (!test_and_set_bit(BIT_TX_SCHEDULED,
+ &ctx->tx_bitmask))
+ schedule_delayed_work(&ctx->tx_work.work, 1);
+ }
}
pending = atomic_dec_return(&ctx->encrypt_pending);
if (!pending && READ_ONCE(ctx->async_notify))
complete(&ctx->async_wait.completion);
-
- if (!ready)
- return;
-
- /* Schedule the transmission */
- if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
- schedule_delayed_work(&ctx->tx_work.work, 1);
}
static int tls_do_encryption(struct sock *sk,