From patchwork Thu Feb 20 13:00:52 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anastasia Belova X-Patchwork-Id: 13983924 Received: from mail-gw01.astralinux.ru (mail-gw01.astralinux.ru [37.230.196.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8DC771F584A; Thu, 20 Feb 2025 13:06:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=37.230.196.243 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740056815; cv=none; b=Jg8v5lmp2DW1g4cnxbus5D51wNfWk43tBPhArGlmlsE14glsyaiIrL6cXOq8fsZjcWsq31kME4hmzzXKmiafgXvB0epd3cmil0YDKvs+B/UzRzuyuY9hjFIKPh7MggC21sK7nwwU6vu+TOZpMERBBS98A1Rq2lvvtkiBuU5Dd+o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740056815; c=relaxed/simple; bh=WCZJrQimBDJD6iuV+oyaGhnj6QAoxK0ucp+seR2Z6ZA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=GEAHwdpAExUfwVuXY8tWcsON6nJLZ497AyScjJnhy1J+SUmLm6rhrAcsE8dw0Yn6QpQ5T98g+zEBZV2+MF6hN9dS1qzEu2M7dYxROQtEvqD2EqHqd5GpLqWDJofVzqPWANtdHzXw1ZbtRacJtXZpGTR2rbUAVVjFQ3gTrODvbQI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=astralinux.ru; spf=pass smtp.mailfrom=astralinux.ru; arc=none smtp.client-ip=37.230.196.243 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=astralinux.ru Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=astralinux.ru Received: from gca-sc-a-srv-ksmg01.astralinux.ru (localhost [127.0.0.1]) by mail-gw01.astralinux.ru (Postfix) with ESMTP id 60BA324BA2; Thu, 20 Feb 2025 16:01:06 +0300 (MSK) Received: from new-mail.astralinux.ru (gca-yc-ruca-srv-mail03.astralinux.ru [10.177.185.108]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail-gw01.astralinux.ru (Postfix) with ESMTPS; Thu, 20 Feb 2025 16:01:02 +0300 (MSK) Received: from localhost.localdomain (unknown [10.177.20.111]) by new-mail.astralinux.ru (Postfix) with ESMTPA id 4YzD0F3VTxz1h0Mx; Thu, 20 Feb 2025 16:01:01 +0300 (MSK) From: Anastasia Belova To: stable@vger.kernel.org, Greg Kroah-Hartman Cc: Anastasia Belova , linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org, Enzo Matsumiya , Steve French Subject: [PATCH 5.10/5.15] smb: client: fix UAF in async decryption Date: Thu, 20 Feb 2025 16:00:52 +0300 Message-ID: <20250220130054.9478-1-abelova@astralinux.ru> X-Mailer: git-send-email 2.47.0 Precedence: bulk X-Mailing-List: linux-cifs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-KSMG-AntiPhishing: NotDetected X-KSMG-AntiSpam-Auth: dkim=none X-KSMG-AntiSpam-Envelope-From: abelova@astralinux.ru X-KSMG-AntiSpam-Info: LuaCore: 51 0.3.51 68896fb0083a027476849bf400a331a2d5d94398, {Tracking_from_domain_doesnt_match_to}, new-mail.astralinux.ru:7.1.1;d41d8cd98f00b204e9800998ecf8427e.com:7.1.1;astralinux.ru:7.1.1;127.0.0.199:7.1.2, FromAlignment: s X-KSMG-AntiSpam-Interceptor-Info: scan successful X-KSMG-AntiSpam-Lua-Profiles: 191143 [Feb 20 2025] X-KSMG-AntiSpam-Method: none X-KSMG-AntiSpam-Rate: 0 X-KSMG-AntiSpam-Status: not_detected X-KSMG-AntiSpam-Version: 6.1.1.11 X-KSMG-AntiVirus: Kaspersky Secure Mail Gateway, version 2.1.0.7854, bases: 2025/02/20 08:57:00 #27373308 X-KSMG-AntiVirus-Status: NotDetected, skipped X-KSMG-LinksScanning: NotDetected X-KSMG-Message-Action: skipped X-KSMG-Rule-ID: 1 From: Enzo Matsumiya commit b0abcd65ec545701b8793e12bc27dc98042b151a upstream. Doing an async decryption (large read) crashes with a slab-use-after-free way down in the crypto API. Reproducer: # mount.cifs -o ...,seal,esize=1 //srv/share /mnt # dd if=/mnt/largefile of=/dev/null ... [ 194.196391] ================================================================== [ 194.196844] BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xc1/0x110 [ 194.197269] Read of size 8 at addr ffff888112bd0448 by task kworker/u77:2/899 [ 194.197707] [ 194.197818] CPU: 12 UID: 0 PID: 899 Comm: kworker/u77:2 Not tainted 6.11.0-lku-00028-gfca3ca14a17a-dirty #43 [ 194.198400] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-3-gd478f380-prebuilt.qemu.org 04/01/2014 [ 194.199046] Workqueue: smb3decryptd smb2_decrypt_offload [cifs] [ 194.200032] Call Trace: [ 194.200191] [ 194.200327] dump_stack_lvl+0x4e/0x70 [ 194.200558] ? gf128mul_4k_lle+0xc1/0x110 [ 194.200809] print_report+0x174/0x505 [ 194.201040] ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [ 194.201352] ? srso_return_thunk+0x5/0x5f [ 194.201604] ? __virt_addr_valid+0xdf/0x1c0 [ 194.201868] ? gf128mul_4k_lle+0xc1/0x110 [ 194.202128] kasan_report+0xc8/0x150 [ 194.202361] ? gf128mul_4k_lle+0xc1/0x110 [ 194.202616] gf128mul_4k_lle+0xc1/0x110 [ 194.202863] ghash_update+0x184/0x210 [ 194.203103] shash_ahash_update+0x184/0x2a0 [ 194.203377] ? __pfx_shash_ahash_update+0x10/0x10 [ 194.203651] ? srso_return_thunk+0x5/0x5f [ 194.203877] ? crypto_gcm_init_common+0x1ba/0x340 [ 194.204142] gcm_hash_assoc_remain_continue+0x10a/0x140 [ 194.204434] crypt_message+0xec1/0x10a0 [cifs] [ 194.206489] ? __pfx_crypt_message+0x10/0x10 [cifs] [ 194.208507] ? srso_return_thunk+0x5/0x5f [ 194.209205] ? srso_return_thunk+0x5/0x5f [ 194.209925] ? srso_return_thunk+0x5/0x5f [ 194.210443] ? srso_return_thunk+0x5/0x5f [ 194.211037] decrypt_raw_data+0x15f/0x250 [cifs] [ 194.212906] ? __pfx_decrypt_raw_data+0x10/0x10 [cifs] [ 194.214670] ? srso_return_thunk+0x5/0x5f [ 194.215193] smb2_decrypt_offload+0x12a/0x6c0 [cifs] This is because TFM is being used in parallel. Fix this by allocating a new AEAD TFM for async decryption, but keep the existing one for synchronous READ cases (similar to what is done in smb3_calc_signature()). Also remove the calls to aead_request_set_callback() and crypto_wait_req() since it's always going to be a synchronous operation. Signed-off-by: Enzo Matsumiya Signed-off-by: Steve French Signed-off-by: Anastasia Belova [ Anastasia: ] --- Backport fix for CVE-2024-50047 fs/cifs/smb2ops.c | 48 +++++++++++++++++++++++++++-------------------- fs/cifs/smb2pdu.c | 6 ++++++ 2 files changed, 34 insertions(+), 20 deletions(-) diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 68f93de2b152..8cfce01cf699 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -4291,7 +4291,7 @@ smb2_get_enc_key(struct TCP_Server_Info *server, __u64 ses_id, int enc, u8 *key) */ static int crypt_message(struct TCP_Server_Info *server, int num_rqst, - struct smb_rqst *rqst, int enc) + struct smb_rqst *rqst, int enc, struct crypto_aead *tfm) { struct smb2_transform_hdr *tr_hdr = (struct smb2_transform_hdr *)rqst[0].rq_iov[0].iov_base; @@ -4302,8 +4302,6 @@ crypt_message(struct TCP_Server_Info *server, int num_rqst, u8 key[SMB3_ENC_DEC_KEY_SIZE]; struct aead_request *req; u8 *iv; - DECLARE_CRYPTO_WAIT(wait); - struct crypto_aead *tfm; unsigned int crypt_len = le32_to_cpu(tr_hdr->OriginalMessageSize); void *creq; @@ -4314,15 +4312,6 @@ crypt_message(struct TCP_Server_Info *server, int num_rqst, return rc; } - rc = smb3_crypto_aead_allocate(server); - if (rc) { - cifs_server_dbg(VFS, "%s: crypto alloc failed\n", __func__); - return rc; - } - - tfm = enc ? server->secmech.ccmaesencrypt : - server->secmech.ccmaesdecrypt; - if ((server->cipher_type == SMB2_ENCRYPTION_AES256_CCM) || (server->cipher_type == SMB2_ENCRYPTION_AES256_GCM)) rc = crypto_aead_setkey(tfm, key, SMB3_GCM256_CRYPTKEY_SIZE); @@ -4361,11 +4350,7 @@ crypt_message(struct TCP_Server_Info *server, int num_rqst, aead_request_set_crypt(req, sg, sg, crypt_len, iv); aead_request_set_ad(req, assoc_data_len); - aead_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, - crypto_req_done, &wait); - - rc = crypto_wait_req(enc ? crypto_aead_encrypt(req) - : crypto_aead_decrypt(req), &wait); + rc = enc ? crypto_aead_encrypt(req) : crypto_aead_decrypt(req); if (!rc && enc) memcpy(&tr_hdr->Signature, sign, SMB2_SIGNATURE_SIZE); @@ -4454,7 +4439,7 @@ smb3_init_transform_rq(struct TCP_Server_Info *server, int num_rqst, /* fill the 1st iov with a transform header */ fill_transform_hdr(tr_hdr, orig_len, old_rq, server->cipher_type); - rc = crypt_message(server, num_rqst, new_rq, 1); + rc = crypt_message(server, num_rqst, new_rq, 1, server->secmech.ccmaesencrypt); cifs_dbg(FYI, "Encrypt message returned %d\n", rc); if (rc) goto err_free; @@ -4480,8 +4465,9 @@ decrypt_raw_data(struct TCP_Server_Info *server, char *buf, unsigned int npages, unsigned int page_data_size, bool is_offloaded) { - struct kvec iov[2]; + struct crypto_aead *tfm; struct smb_rqst rqst = {NULL}; + struct kvec iov[2]; int rc; iov[0].iov_base = buf; @@ -4496,9 +4482,31 @@ decrypt_raw_data(struct TCP_Server_Info *server, char *buf, rqst.rq_pagesz = PAGE_SIZE; rqst.rq_tailsz = (page_data_size % PAGE_SIZE) ? : PAGE_SIZE; - rc = crypt_message(server, 1, &rqst, 0); + if (is_offloaded) { + if ((server->cipher_type == SMB2_ENCRYPTION_AES128_GCM) || + (server->cipher_type == SMB2_ENCRYPTION_AES256_GCM)) + tfm = crypto_alloc_aead("gcm(aes)", 0, 0); + else + tfm = crypto_alloc_aead("ccm(aes)", 0, 0); + if (IS_ERR(tfm)) { + rc = PTR_ERR(tfm); + cifs_server_dbg(VFS, "%s: Failed alloc decrypt TFM, rc=%d\n", __func__, rc); + + return rc; + } + } else { + if (unlikely(!server->secmech.ccmaesdecrypt)) + return -EIO; + + tfm = server->secmech.ccmaesdecrypt; + } + + rc = crypt_message(server, 1, &rqst, 0, tfm); cifs_dbg(FYI, "Decrypt message returned %d\n", rc); + if (is_offloaded) + crypto_free_aead(tfm); + if (rc) return rc; diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c index 03651cc6b7a5..245e2dd5a194 100644 --- a/fs/cifs/smb2pdu.c +++ b/fs/cifs/smb2pdu.c @@ -998,6 +998,12 @@ SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses) else cifs_server_dbg(VFS, "Missing expected negotiate contexts\n"); } + + if (server->cipher_type && !rc) { + rc = smb3_crypto_aead_allocate(server); + if (rc) + cifs_server_dbg(VFS, "%s: crypto alloc failed, rc=%d\n", __func__, rc); + } neg_exit: free_rsp_buf(resp_buftype, rsp); return rc;