From 15b11a1da6a4b7c6b8bb37883f52b544dee2b8fd Mon Sep 17 00:00:00 2001 From: zhenwei pi Date: Thu, 3 Aug 2023 10:43:14 +0800 Subject: [PATCH] cryptodev: Handle unexpected request to avoid crash Generally guest side should discover which services the device is able to offer, then do requests on device. However it's also possible to break this rule in a guest. Handle unexpected request here to avoid NULL pointer dereference. Fixes: e7a775fd ('cryptodev: Account statistics') Cc: Gonglei Cc: Mauro Matteo Cascella Cc: Xiao Lei Cc: Yongkang Jia Reported-by: Yiming Tao Signed-off-by: zhenwei pi Message-Id: <20230803024314.29962-3-pizhenwei@bytedance.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- backends/cryptodev.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/backends/cryptodev.c b/backends/cryptodev.c index 7d29517843..4d183f7237 100644 --- a/backends/cryptodev.c +++ b/backends/cryptodev.c @@ -191,6 +191,11 @@ static int cryptodev_backend_account(CryptoDevBackend *backend, if (algtype == QCRYPTODEV_BACKEND_ALG_ASYM) { CryptoDevBackendAsymOpInfo *asym_op_info = op_info->u.asym_op_info; len = asym_op_info->src_len; + + if (unlikely(!backend->asym_stat)) { + error_report("cryptodev: Unexpected asym operation"); + return -VIRTIO_CRYPTO_NOTSUPP; + } switch (op_info->op_code) { case VIRTIO_CRYPTO_AKCIPHER_ENCRYPT: CryptodevAsymStatIncEncrypt(backend, len); @@ -210,6 +215,11 @@ static int cryptodev_backend_account(CryptoDevBackend *backend, } else if (algtype == QCRYPTODEV_BACKEND_ALG_SYM) { CryptoDevBackendSymOpInfo *sym_op_info = op_info->u.sym_op_info; len = sym_op_info->src_len; + + if (unlikely(!backend->sym_stat)) { + error_report("cryptodev: Unexpected sym operation"); + return -VIRTIO_CRYPTO_NOTSUPP; + } switch (op_info->op_code) { case VIRTIO_CRYPTO_CIPHER_ENCRYPT: CryptodevSymStatIncEncrypt(backend, len);