From: Jakub Kicinski kuba@kernel.org
commit 8590541473188741055d27b955db0777569438e3 upstream.
Since we're setting the CRYPTO_TFM_REQ_MAY_BACKLOG flag on our requests to the crypto API, crypto_aead_{encrypt,decrypt} can return -EBUSY instead of -EINPROGRESS in valid situations. For example, when the cryptd queue for AESNI is full (easy to trigger with an artificially low cryptd.cryptd_max_cpu_qlen), requests will be enqueued to the backlog but still processed. In that case, the async callback will also be called twice: first with err == -EINPROGRESS, which it seems we can just ignore, then with err == 0.
Compared to Sabrina's original patch this version uses the new tls_*crypt_async_wait() helpers and converts the EBUSY to EINPROGRESS to avoid having to modify all the error handling paths. The handling is identical.
Fixes: a54667f6728c ("tls: Add support for encryption using async offload accelerator") Fixes: 94524d8fc965 ("net/tls: Add support for async decryption of tls records") Co-developed-by: Sabrina Dubroca sd@queasysnail.net Signed-off-by: Sabrina Dubroca sd@queasysnail.net Link: https://lore.kernel.org/netdev/9681d1febfec295449a62300938ed2ae66983f28.1694... Signed-off-by: Jakub Kicinski kuba@kernel.org Reviewed-by: Simon Horman horms@kernel.org Signed-off-by: David S. Miller davem@davemloft.net [v5.15: fixed contextual merge-conflicts in tls_decrypt_done and tls_encrypt_done] Cc: stable@vger.kernel.org # 5.15 Signed-off-by: Shaoying Xu shaoyi@amazon.com --- net/tls/tls_sw.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)
diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c index 40b96780e13d..90f6cbe5cd5d 100644 --- a/net/tls/tls_sw.c +++ b/net/tls/tls_sw.c @@ -175,6 +175,17 @@ static void tls_decrypt_done(struct crypto_async_request *req, int err) struct sk_buff *skb; unsigned int pages;
+ /* If requests get too backlogged crypto API returns -EBUSY and calls + * ->complete(-EINPROGRESS) immediately followed by ->complete(0) + * to make waiting for backlog to flush with crypto_wait_req() easier. + * First wait converts -EBUSY -> -EINPROGRESS, and the second one + * -EINPROGRESS -> 0. + * We have a single struct crypto_async_request per direction, this + * scheme doesn't help us, so just ignore the first ->complete(). + */ + if (err == -EINPROGRESS) + return; + skb = (struct sk_buff *)req->data; tls_ctx = tls_get_ctx(skb->sk); ctx = tls_sw_ctx_rx(tls_ctx); @@ -273,6 +284,10 @@ static int tls_do_decryption(struct sock *sk, }
ret = crypto_aead_decrypt(aead_req); + if (ret == -EBUSY) { + ret = tls_decrypt_async_wait(ctx); + ret = ret ?: -EINPROGRESS; + } if (ret == -EINPROGRESS) { if (darg->async) return 0; @@ -455,6 +470,9 @@ static void tls_encrypt_done(struct crypto_async_request *req, int err) struct tls_rec *rec; bool ready = false;
+ if (err == -EINPROGRESS) /* see the comment in tls_decrypt_done() */ + return; + rec = container_of(aead_req, struct tls_rec, aead_req); msg_en = &rec->msg_encrypted;
@@ -551,6 +569,10 @@ static int tls_do_encryption(struct sock *sk, atomic_inc(&ctx->encrypt_pending);
rc = crypto_aead_encrypt(aead_req); + if (rc == -EBUSY) { + rc = tls_encrypt_async_wait(ctx); + rc = rc ?: -EINPROGRESS; + } if (!rc || rc != -EINPROGRESS) { atomic_dec(&ctx->encrypt_pending); sge->offset -= prot->prepend_size;