From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 27E0D21ABA6 for ; Tue, 29 Apr 2025 15:34:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745940849; cv=none; b=m+I5ycXXA7zEeUT3R9v9kYVZNzl49Pfv+8VOD+MjgCNkRdt3YsbvNJfBY5keyxFNGqHkwOnRLGG7/KyUK/N6vwH/HMQeriwam7KZwkTz5jCqCFFOJhCAp3jvx/01wQ+rSZd17zbcJL7ZINJKtjLLAAAGgatud73v2t4ikfaFPR4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745940849; c=relaxed/simple; bh=IEo4VOZd5YxIifc6V0dQx7/4kej0lsbDyKXbI7KYj9Q=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=k6lJFP3h9pxf9k1QZfdCnDI56mBl61jF9w+FfqH4t0XKWuxqiBVz6zGJC81K/zeKQrM9ycsKX7ek3Pi+Z5ub90IRykEHJw5Ol0ZYC9QHA8to5Ms9cQYczBVwxcQn9QlVPqf4emfFps5pOVEyfF5trbfsofG4/wnvmWto/F45v84= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zPFKM42c; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="zPFKM42c" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1C57EC4CEE3; Tue, 29 Apr 2025 15:34:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745940848; bh=IEo4VOZd5YxIifc6V0dQx7/4kej0lsbDyKXbI7KYj9Q=; h=Subject:To:Cc:From:Date:From; b=zPFKM42cJCtgeaqGA5SGbRXyQWwMzLhgDxJYtpTEY27Bh8V0AC5Boegkm/N5r5Ce4 0ahMN4LJ5tLW9VBq3KaV5VPwY0hmMVEhXdj5MKtF2zwAn57Gn8DUpWlqJLuR1xwU2F FJSv9UwOvX615P0VAOXxU8D48fUtO7dfHUSqKijc= Subject: FAILED: patch "[PATCH] smb: client: fix UAF in decryption with multichannel" failed to apply to 5.15-stable tree To: pc@manguebit.com,dhowells@redhat.com,stfrench@microsoft.com Cc: From: Date: Tue, 29 Apr 2025 17:34:05 +0200 Message-ID: <2025042904-zap-drench-9729@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 9502dd5c7029902f4a425bf959917a5a9e7c0e50 # git commit -s git send-email --to '' --in-reply-to '2025042904-zap-drench-9729@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 9502dd5c7029902f4a425bf959917a5a9e7c0e50 Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Wed, 9 Apr 2025 11:14:21 -0300 Subject: [PATCH] smb: client: fix UAF in decryption with multichannel After commit f7025d861694 ("smb: client: allocate crypto only for primary server") and commit b0abcd65ec54 ("smb: client: fix UAF in async decryption"), the channels started reusing AEAD TFM from primary channel to perform synchronous decryption, but that can't done as there could be multiple cifsd threads (one per channel) simultaneously accessing it to perform decryption. This fixes the following KASAN splat when running fstest generic/249 with 'vers=3.1.1,multichannel,max_channels=4,seal' against Windows Server 2022: BUG: KASAN: slab-use-after-free in gf128mul_4k_lle+0xba/0x110 Read of size 8 at addr ffff8881046c18a0 by task cifsd/986 CPU: 3 UID: 0 PID: 986 Comm: cifsd Not tainted 6.15.0-rc1 #1 PREEMPT(voluntary) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-3.fc41 04/01/2014 Call Trace: dump_stack_lvl+0x5d/0x80 print_report+0x156/0x528 ? gf128mul_4k_lle+0xba/0x110 ? __virt_addr_valid+0x145/0x300 ? __phys_addr+0x46/0x90 ? gf128mul_4k_lle+0xba/0x110 kasan_report+0xdf/0x1a0 ? gf128mul_4k_lle+0xba/0x110 gf128mul_4k_lle+0xba/0x110 ghash_update+0x189/0x210 shash_ahash_update+0x295/0x370 ? __pfx_shash_ahash_update+0x10/0x10 ? __pfx_shash_ahash_update+0x10/0x10 ? __pfx_extract_iter_to_sg+0x10/0x10 ? ___kmalloc_large_node+0x10e/0x180 ? __asan_memset+0x23/0x50 crypto_ahash_update+0x3c/0xc0 gcm_hash_assoc_remain_continue+0x93/0xc0 crypt_message+0xe09/0xec0 [cifs] ? __pfx_crypt_message+0x10/0x10 [cifs] ? _raw_spin_unlock+0x23/0x40 ? __pfx_cifs_readv_from_socket+0x10/0x10 [cifs] decrypt_raw_data+0x229/0x380 [cifs] ? __pfx_decrypt_raw_data+0x10/0x10 [cifs] ? __pfx_cifs_read_iter_from_socket+0x10/0x10 [cifs] smb3_receive_transform+0x837/0xc80 [cifs] ? __pfx_smb3_receive_transform+0x10/0x10 [cifs] ? __pfx___might_resched+0x10/0x10 ? __pfx_smb3_is_transform_hdr+0x10/0x10 [cifs] cifs_demultiplex_thread+0x692/0x1570 [cifs] ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs] ? rcu_is_watching+0x20/0x50 ? rcu_lockdep_current_cpu_online+0x62/0xb0 ? find_held_lock+0x32/0x90 ? kvm_sched_clock_read+0x11/0x20 ? local_clock_noinstr+0xd/0xd0 ? trace_irq_enable.constprop.0+0xa8/0xe0 ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs] kthread+0x1fe/0x380 ? kthread+0x10f/0x380 ? __pfx_kthread+0x10/0x10 ? local_clock_noinstr+0xd/0xd0 ? ret_from_fork+0x1b/0x60 ? local_clock+0x15/0x30 ? lock_release+0x29b/0x390 ? rcu_is_watching+0x20/0x50 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x31/0x60 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 Tested-by: David Howells Reported-by: Steve French Closes: https://lore.kernel.org/r/CAH2r5mu6Yc0-RJXM3kFyBYUB09XmXBrNodOiCVR4EDrmxq5Szg@mail.gmail.com Fixes: f7025d861694 ("smb: client: allocate crypto only for primary server") Fixes: b0abcd65ec54 ("smb: client: fix UAF in async decryption") Signed-off-by: Paulo Alcantara (Red Hat) Signed-off-by: Steve French diff --git a/fs/smb/client/cifsencrypt.c b/fs/smb/client/cifsencrypt.c index e69968e88fe7..35892df7335c 100644 --- a/fs/smb/client/cifsencrypt.c +++ b/fs/smb/client/cifsencrypt.c @@ -704,18 +704,12 @@ cifs_crypto_secmech_release(struct TCP_Server_Info *server) cifs_free_hash(&server->secmech.md5); cifs_free_hash(&server->secmech.sha512); - if (!SERVER_IS_CHAN(server)) { - if (server->secmech.enc) { - crypto_free_aead(server->secmech.enc); - server->secmech.enc = NULL; - } - - if (server->secmech.dec) { - crypto_free_aead(server->secmech.dec); - server->secmech.dec = NULL; - } - } else { + if (server->secmech.enc) { + crypto_free_aead(server->secmech.enc); server->secmech.enc = NULL; + } + if (server->secmech.dec) { + crypto_free_aead(server->secmech.dec); server->secmech.dec = NULL; } } diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c index 41d8cd20b25f..3f7fe74688a9 100644 --- a/fs/smb/client/smb2ops.c +++ b/fs/smb/client/smb2ops.c @@ -4555,9 +4555,9 @@ decrypt_raw_data(struct TCP_Server_Info *server, char *buf, return rc; } } else { - if (unlikely(!server->secmech.dec)) - return -EIO; - + rc = smb3_crypto_aead_allocate(server); + if (unlikely(rc)) + return rc; tfm = server->secmech.dec; } diff --git a/fs/smb/client/smb2pdu.c b/fs/smb/client/smb2pdu.c index 81e05db8e4d5..c4d52bebd37d 100644 --- a/fs/smb/client/smb2pdu.c +++ b/fs/smb/client/smb2pdu.c @@ -1252,15 +1252,8 @@ SMB2_negotiate(const unsigned int xid, cifs_server_dbg(VFS, "Missing expected negotiate contexts\n"); } - if (server->cipher_type && !rc) { - if (!SERVER_IS_CHAN(server)) { - rc = smb3_crypto_aead_allocate(server); - } else { - /* For channels, just reuse the primary server crypto secmech. */ - server->secmech.enc = server->primary_server->secmech.enc; - server->secmech.dec = server->primary_server->secmech.dec; - } - } + if (server->cipher_type && !rc) + rc = smb3_crypto_aead_allocate(server); neg_exit: free_rsp_buf(resp_buftype, rsp); return rc;