[PATCH 5.15 08/23] tls: rx: simplify async wait

Greg Kroah-Hartman
2024-05-23T13:18:46Z

5.15-stable review patch. If anyone has any objections, please let me know.

------------------

From: Jakub Kicinski <kuba@kernel.org>

commit 37943f047bfb88ba4dfc7a522563f57c86d088a0 upstream.

Since we are protected from async completions by decrypt_compl_lock
we can drop the async_notify and reinit the completion before we
start waiting.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: aec7961916f3 ("tls: fix race between async notify and socket close")
Signed-off-by: Shaoying Xu <shaoyi@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/net/tls.h | 1 -
net/tls/tls_sw.c | 14 ++------------
2 files changed, 2 insertions(+), 13 deletions(-)

--- a/include/net/tls.h
+++ b/include/net/tls.h
@@ -150,7 +150,6 @@ struct tls_sw_context_rx {
atomic_t decrypt_pending;
/* protect crypto_wait with decrypt_pending*/
spinlock_t decrypt_compl_lock;
- bool async_notify;
};

struct tls_record_info {
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -174,7 +174,6 @@ static void tls_decrypt_done(struct cryp
struct scatterlist *sg;
struct sk_buff *skb;
unsigned int pages;
- int pending;

skb = (struct sk_buff *)req->data;
tls_ctx = tls_get_ctx(skb->sk);
@@ -222,9 +221,7 @@ static void tls_decrypt_done(struct cryp
kfree(aead_req);

spin_lock_bh(&ctx->decrypt_compl_lock);
- pending = atomic_dec_return(&ctx->decrypt_pending);
-
- if (!pending && ctx->async_notify)
+ if (!atomic_dec_return(&ctx->decrypt_pending))
complete(&ctx->async_wait.completion);
spin_unlock_bh(&ctx->decrypt_compl_lock);
}
@@ -1917,7 +1914,7 @@ recv_end:

/* Wait for all previously submitted records to be decrypted */
spin_lock_bh(&ctx->decrypt_compl_lock);
- ctx->async_notify = true;
+ reinit_completion(&ctx->async_wait.completion);
pending = atomic_read(&ctx->decrypt_pending);
spin_unlock_bh(&ctx->decrypt_compl_lock);
if (pending) {
@@ -1929,15 +1926,8 @@ recv_end:
decrypted = 0;
goto end;
}
- } else {
- reinit_completion(&ctx->async_wait.completion);
}

- /* There can be no concurrent accesses, since we have no
- * pending decrypt operations
- */
- WRITE_ONCE(ctx->async_notify, false);
-
/* Drain records from the rx_list & copy if required */
if (is_peek || is_kvec)
err = process_rx_list(ctx, msg, &control, copied,