From patchwork Tue Jun 13 18:06:03 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pauli Virtanen X-Patchwork-Id: 692701 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3C6F9EB64D8 for ; Tue, 13 Jun 2023 18:06:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231840AbjFMSGR (ORCPT ); Tue, 13 Jun 2023 14:06:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230462AbjFMSGP (ORCPT ); Tue, 13 Jun 2023 14:06:15 -0400 Received: from meesny.iki.fi (meesny.iki.fi [IPv6:2001:67c:2b0:1c1::201]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F3EEE19B1 for ; Tue, 13 Jun 2023 11:06:10 -0700 (PDT) Received: from monolith.lan (91-152-120-101.elisa-laajakaista.fi [91.152.120.101]) (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) (Authenticated sender: pav) by meesny.iki.fi (Postfix) with ESMTPSA id 4Qgc1Y0tCxz1016; Tue, 13 Jun 2023 21:06:09 +0300 (EEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=iki.fi; s=meesny; t=1686679569; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=MMkx3MMhFVCti2aTyzxtfPJqeA/J5JTxrn4m+6aEISs=; b=av0KGDub068qKmRDtM5UWllEtlhm2gCw8QL1g1pYUl63nTT4leNfzHC7rQWGP/zGzOYgac yJsbMqOSsl+M5wK+b2gjgQ5S7JDa55iNPQrETQQKH33ALa6EpRiOJPZdvhJXz+ZUi7z8i6 FDbtw+saH+Fd9wgOpGKPDx5Lw2Ef4Fg= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=iki.fi; s=meesny; t=1686679569; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=MMkx3MMhFVCti2aTyzxtfPJqeA/J5JTxrn4m+6aEISs=; b=FMXNJNZYIykCmNDBTcgO6zhgGUfY62gOIAzRfhAGF+/M+crqQf4YebydOtCaxAlFsl3zPU CqDCzzGw+QcT99Ob2WEWzhc4fTPh0iGOCHHrDAmMZrhGruHady+IVNS6YegpzmsNnUtDSg AHRcJW1GScRwmlRYrNKzJ5zCNtUX1Eo= ARC-Authentication-Results: i=1; ORIGINATING; auth=pass smtp.auth=pav smtp.mailfrom=pav@iki.fi ARC-Seal: i=1; s=meesny; d=iki.fi; t=1686679569; a=rsa-sha256; cv=none; b=B6NU0Us86ya9JGeTbm4TEzG7Mx7D5+hvO2idPWH7Y0rP9Z+XkkUkw7n4aaKL54vpmmPfXV 6l4pZUOwAG2r05kEYuSee0ufH3iA62/fHGw3IvN85ZHjhp9apZH3xrwS952ArtXcY+Z7Xy sdMqlYTCuWck36ne6VIvb96m89V7ZM0= From: Pauli Virtanen To: linux-bluetooth@vger.kernel.org Cc: Pauli Virtanen Subject: [PATCH v2 2/3] Bluetooth: hci_event: call disconnect callback before deleting conn Date: Tue, 13 Jun 2023 21:06:03 +0300 Message-Id: <35ee31b8c22cfe9e53675183d314c1f0b64e3ac0.1686589290.git.pav@iki.fi> X-Mailer: git-send-email 2.40.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org In hci_cs_disconnect, we do hci_conn_del even if disconnection failed. ISO, L2CAP and SCO connections refer to the hci_conn without hci_conn_get, so disconn_cfm must be called so they can clean up their conn, otherwise use-after-free occurs. ISO: ========================================================== iso_sock_connect:880: sk 00000000eabd6557 iso_connect_cis:356: 70:1a:b8:98:ff:a2 -> 28:3d:c2:4a:7e:da ... iso_conn_add:140: hcon 000000001696f1fd conn 00000000b6251073 hci_dev_put:1487: hci0 orig refcnt 17 __iso_chan_add:214: conn 00000000b6251073 iso_sock_clear_timer:117: sock 00000000eabd6557 state 3 ... hci_rx_work:4085: hci0 Event packet hci_event_packet:7601: hci0: event 0x0f hci_cmd_status_evt:4346: hci0: opcode 0x0406 hci_cs_disconnect:2760: hci0: status 0x0c hci_sent_cmd_data:3107: hci0 opcode 0x0406 hci_conn_del:1151: hci0 hcon 000000001696f1fd handle 2560 hci_conn_unlink:1102: hci0: hcon 000000001696f1fd hci_conn_drop:1451: hcon 00000000d8521aaf orig refcnt 2 hci_chan_list_flush:2780: hcon 000000001696f1fd hci_dev_put:1487: hci0 orig refcnt 21 hci_dev_put:1487: hci0 orig refcnt 20 hci_req_cmd_complete:3978: opcode 0x0406 status 0x0c ... ... iso_sock_sendmsg:1098: sock 00000000dea5e2e0, sk 00000000eabd6557 BUG: kernel NULL pointer dereference, address: 0000000000000668 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-1.fc38 04/01/2014 RIP: 0010:iso_sock_sendmsg (net/bluetooth/iso.c:1112) bluetooth ========================================================== L2CAP: ================================================================== hci_cmd_status_evt:4359: hci0: opcode 0x0406 hci_cs_disconnect:2760: hci0: status 0x0c hci_sent_cmd_data:3085: hci0 opcode 0x0406 hci_conn_del:1151: hci0 hcon ffff88800c999000 handle 3585 hci_conn_unlink:1102: hci0: hcon ffff88800c999000 hci_chan_list_flush:2780: hcon ffff88800c999000 hci_chan_del:2761: hci0 hcon ffff88800c999000 chan ffff888018ddd280 ... BUG: KASAN: slab-use-after-free in hci_send_acl+0x2d/0x540 [bluetooth] Read of size 8 at addr ffff888018ddd298 by task bluetoothd/1175 CPU: 0 PID: 1175 Comm: bluetoothd Tainted: G E 6.4.0-rc4+ #2 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-1.fc38 04/01/2014 Call Trace: dump_stack_lvl+0x5b/0x90 print_report+0xcf/0x670 ? __virt_addr_valid+0xf8/0x180 ? hci_send_acl+0x2d/0x540 [bluetooth] kasan_report+0xa8/0xe0 ? hci_send_acl+0x2d/0x540 [bluetooth] hci_send_acl+0x2d/0x540 [bluetooth] ? __pfx___lock_acquire+0x10/0x10 l2cap_chan_send+0x1fd/0x1300 [bluetooth] ? l2cap_sock_sendmsg+0xf2/0x170 [bluetooth] ? __pfx_l2cap_chan_send+0x10/0x10 [bluetooth] ? lock_release+0x1d5/0x3c0 ? mark_held_locks+0x1a/0x90 l2cap_sock_sendmsg+0x100/0x170 [bluetooth] sock_write_iter+0x275/0x280 ? __pfx_sock_write_iter+0x10/0x10 ? __pfx___lock_acquire+0x10/0x10 do_iter_readv_writev+0x176/0x220 ? __pfx_do_iter_readv_writev+0x10/0x10 ? find_held_lock+0x83/0xa0 ? selinux_file_permission+0x13e/0x210 do_iter_write+0xda/0x340 vfs_writev+0x1b4/0x400 ? __pfx_vfs_writev+0x10/0x10 ? __seccomp_filter+0x112/0x750 ? populate_seccomp_data+0x182/0x220 ? __fget_light+0xdf/0x100 ? do_writev+0x19d/0x210 do_writev+0x19d/0x210 ? __pfx_do_writev+0x10/0x10 ? mark_held_locks+0x1a/0x90 do_syscall_64+0x60/0x90 ? lockdep_hardirqs_on_prepare+0x149/0x210 ? do_syscall_64+0x6c/0x90 ? lockdep_hardirqs_on_prepare+0x149/0x210 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7ff45cb23e64 Code: 15 d1 1f 0d 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 80 3d 9d a7 0d 00 00 74 13 b8 14 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 48 83 ec 28 89 54 24 1c 48 89 RSP: 002b:00007fff21ae09b8 EFLAGS: 00000202 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007ff45cb23e64 RDX: 0000000000000001 RSI: 00007fff21ae0aa0 RDI: 0000000000000017 RBP: 00007fff21ae0aa0 R08: 000000000095a8a0 R09: 0000607000053f40 R10: 0000000000000001 R11: 0000000000000202 R12: 00007fff21ae0ac0 R13: 00000fffe435c150 R14: 00007fff21ae0a80 R15: 000060f000000040 Allocated by task 771: kasan_save_stack+0x33/0x60 kasan_set_track+0x25/0x30 __kasan_kmalloc+0xaa/0xb0 hci_chan_create+0x67/0x1b0 [bluetooth] l2cap_conn_add.part.0+0x17/0x590 [bluetooth] l2cap_connect_cfm+0x266/0x6b0 [bluetooth] hci_le_remote_feat_complete_evt+0x167/0x310 [bluetooth] hci_event_packet+0x38d/0x800 [bluetooth] hci_rx_work+0x287/0xb20 [bluetooth] process_one_work+0x4f7/0x970 worker_thread+0x8f/0x620 kthread+0x17f/0x1c0 ret_from_fork+0x2c/0x50 Freed by task 771: kasan_save_stack+0x33/0x60 kasan_set_track+0x25/0x30 kasan_save_free_info+0x2e/0x50 ____kasan_slab_free+0x169/0x1c0 slab_free_freelist_hook+0x9e/0x1c0 __kmem_cache_free+0xc0/0x310 hci_chan_list_flush+0x46/0x90 [bluetooth] hci_conn_cleanup+0x7d/0x330 [bluetooth] hci_cs_disconnect+0x35d/0x530 [bluetooth] hci_cmd_status_evt+0xef/0x2b0 [bluetooth] hci_event_packet+0x38d/0x800 [bluetooth] hci_rx_work+0x287/0xb20 [bluetooth] process_one_work+0x4f7/0x970 worker_thread+0x8f/0x620 kthread+0x17f/0x1c0 ret_from_fork+0x2c/0x50 ================================================================== Fixes: b8d290525e39 ("Bluetooth: clean up connection in hci_cs_disconnect") Signed-off-by: Pauli Virtanen --- Notes: v2: call disconn_cfm for all conn types, as L2CAP also crashes. Correct commit in Fixes tag. net/bluetooth/hci_event.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index 8187c9f827fa..a6dabc5b6fad 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -2784,6 +2784,9 @@ static void hci_cs_disconnect(struct hci_dev *hdev, u8 status) hci_enable_advertising(hdev); } + /* Inform sockets conn is gone before we delete it */ + hci_disconn_cfm(conn, HCI_ERROR_UNSPECIFIED); + goto done; }