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2023-10-25Bluetooth: hci_sock: Correctly bounds check and pad HCI_MON_NEW_INDEX nameKees Cook1-1/+2
commit cb3871b1cd135a6662b732fbc6b3db4afcdb4a64 upstream. The code pattern of memcpy(dst, src, strlen(src)) is almost always wrong. In this case it is wrong because it leaves memory uninitialized if it is less than sizeof(ni->name), and overflows ni->name when longer. Normally strtomem_pad() could be used here, but since ni->name is a trailing array in struct hci_mon_new_index, compilers that don't support -fstrict-flex-arrays=3 can't tell how large this array is via __builtin_object_size(). Instead, open-code the helper and use sizeof() since it will work correctly. Additionally mark ni->name as __nonstring since it appears to not be a %NUL terminated C string. Cc: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Cc: Edward AD <twuufnxlz@gmail.com> Cc: Marcel Holtmann <marcel@holtmann.org> Cc: Johan Hedberg <johan.hedberg@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: linux-bluetooth@vger.kernel.org Cc: netdev@vger.kernel.org Fixes: 18f547f3fc07 ("Bluetooth: hci_sock: fix slab oob read in create_monitor_event") Link: https://lore.kernel.org/lkml/202310110908.F2639D3276@keescook/ Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25Bluetooth: hci_sock: fix slab oob read in create_monitor_eventEdward AD1-1/+1
commit 18f547f3fc074500ab5d419cf482240324e73a7e upstream. When accessing hdev->name, the actual string length should prevail Reported-by: syzbot+c90849c50ed209d77689@syzkaller.appspotmail.com Fixes: dcda165706b9 ("Bluetooth: hci_core: Fix build warnings") Signed-off-by: Edward AD <twuufnxlz@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25Bluetooth: hci_event: Fix using memcmp when comparing keysLuiz Augusto von Dentz1-5/+7
[ Upstream commit b541260615f601ae1b5d6d0cc54e790de706303b ] memcmp is not consider safe to use with cryptographic secrets: 'Do not use memcmp() to compare security critical data, such as cryptographic secrets, because the required CPU time depends on the number of equal bytes.' While usage of memcmp for ZERO_KEY may not be considered a security critical data, it can lead to more usage of memcmp with pairing keys which could introduce more security problems. Fixes: 455c2ff0a558 ("Bluetooth: Fix BR/EDR out-of-band pairing with only initiator data") Fixes: 33155c4aae52 ("Bluetooth: hci_event: Ignore NULL link key") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-25Bluetooth: hci_core: Fix build warningsLuiz Augusto von Dentz1-3/+5
[ Upstream commit dcda165706b9fbfd685898d46a6749d7d397e0c0 ] This fixes the following warnings: net/bluetooth/hci_core.c: In function ‘hci_register_dev’: net/bluetooth/hci_core.c:2620:54: warning: ‘%d’ directive output may be truncated writing between 1 and 10 bytes into a region of size 5 [-Wformat-truncation=] 2620 | snprintf(hdev->name, sizeof(hdev->name), "hci%d", id); | ^~ net/bluetooth/hci_core.c:2620:50: note: directive argument in the range [0, 2147483647] 2620 | snprintf(hdev->name, sizeof(hdev->name), "hci%d", id); | ^~~~~~~ net/bluetooth/hci_core.c:2620:9: note: ‘snprintf’ output between 5 and 14 bytes into a destination of size 8 2620 | snprintf(hdev->name, sizeof(hdev->name), "hci%d", id); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-25Bluetooth: Avoid redundant authenticationYing Hsu1-28/+35
[ Upstream commit 1d8e801422d66e4b8c7b187c52196bef94eed887 ] While executing the Android 13 CTS Verifier Secure Server test on a ChromeOS device, it was observed that the Bluetooth host initiates authentication for an RFCOMM connection after SSP completes. When this happens, some Intel Bluetooth controllers, like AC9560, would disconnect with "Connection Rejected due to Security Reasons (0x0e)". Historically, BlueZ did not mandate this authentication while an authenticated combination key was already in use for the connection. This behavior was changed since commit 7b5a9241b780 ("Bluetooth: Introduce requirements for security level 4"). So, this patch addresses the aforementioned disconnection issue by restoring the previous behavior. Signed-off-by: Ying Hsu <yinghsu@chromium.org> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-25Bluetooth: avoid memcmp() out of bounds warningArnd Bergmann1-1/+1
commit 9d1a3c74746428102d55371fbf74b484733937d9 upstream. bacmp() is a wrapper around memcpy(), which contain compile-time checks for buffer overflow. Since the hci_conn_request_evt() also calls bt_dev_dbg() with an implicit NULL pointer check, the compiler is now aware of a case where 'hdev' is NULL and treats this as meaning that zero bytes are available: In file included from net/bluetooth/hci_event.c:32: In function 'bacmp', inlined from 'hci_conn_request_evt' at net/bluetooth/hci_event.c:3276:7: include/net/bluetooth/bluetooth.h:364:16: error: 'memcmp' specified bound 6 exceeds source size 0 [-Werror=stringop-overread] 364 | return memcmp(ba1, ba2, sizeof(bdaddr_t)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Add another NULL pointer check before the bacmp() to ensure the compiler understands the code flow enough to not warn about it. Since the patch that introduced the warning is marked for stable backports, this one should also go that way to avoid introducing build regressions. Fixes: 1ffc6f8cc332 ("Bluetooth: Reject connection with the device which has same BD_ADDR") Cc: Kees Cook <keescook@chromium.org> Cc: "Lee, Chun-Yi" <jlee@suse.com> Cc: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Cc: Marcel Holtmann <marcel@holtmann.org> Cc: stable@vger.kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25Bluetooth: hci_event: Fix coding styleLuiz Augusto von Dentz1-2/+1
commit 35d91d95a0cd61ebb90e0246dc917fd25e519b8c upstream. This fixes the following code style problem: ERROR: that open brace { should be on the previous line + if (!bacmp(&hdev->bdaddr, &ev->bdaddr)) + { Fixes: 1ffc6f8cc332 ("Bluetooth: Reject connection with the device which has same BD_ADDR") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25Bluetooth: Fix a refcnt underflow problem for hci_connZiyang Xuan1-2/+2
commit c7f59461f5a78994613afc112cdd73688aef9076 upstream. Syzbot reports a warning as follows: WARNING: CPU: 1 PID: 26946 at net/bluetooth/hci_conn.c:619 hci_conn_timeout+0x122/0x210 net/bluetooth/hci_conn.c:619 ... Call Trace: <TASK> process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 </TASK> It is because the HCI_EV_SIMPLE_PAIR_COMPLETE event handler drops hci_conn directly without check Simple Pairing whether be enabled. But the Simple Pairing process can only be used if both sides have the support enabled in the host stack. Add hci_conn_ssp_enabled() for hci_conn in HCI_EV_IO_CAPA_REQUEST and HCI_EV_SIMPLE_PAIR_COMPLETE event handlers to fix the problem. Fixes: 0493684ed239 ("[Bluetooth] Disable disconnect timer during Simple Pairing") Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25Bluetooth: Reject connection with the device which has same BD_ADDRLee, Chun-Yi2-0/+20
commit 1ffc6f8cc33268731fcf9629fc4438f6db1191fc upstream. This change is used to relieve CVE-2020-26555. The description of the CVE: Bluetooth legacy BR/EDR PIN code pairing in Bluetooth Core Specification 1.0B through 5.2 may permit an unauthenticated nearby device to spoof the BD_ADDR of the peer device to complete pairing without knowledge of the PIN. [1] The detail of this attack is in IEEE paper: BlueMirror: Reflections on Bluetooth Pairing and Provisioning Protocols [2] It's a reflection attack. The paper mentioned that attacker can induce the attacked target to generate null link key (zero key) without PIN code. In BR/EDR, the key generation is actually handled in the controller which is below HCI. A condition of this attack is that attacker should change the BR_ADDR of his hacking device (Host B) to equal to the BR_ADDR with the target device being attacked (Host A). Thus, we reject the connection with device which has same BD_ADDR both on HCI_Create_Connection and HCI_Connection_Request to prevent the attack. A similar implementation also shows in btstack project. [3][4] Cc: stable@vger.kernel.org Link: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-26555 [1] Link: https://ieeexplore.ieee.org/abstract/document/9474325/authors#authors [2] Link: https://github.com/bluekitchen/btstack/blob/master/src/hci.c#L3523 [3] Link: https://github.com/bluekitchen/btstack/blob/master/src/hci.c#L7297 [4] Signed-off-by: Lee, Chun-Yi <jlee@suse.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25Bluetooth: hci_event: Ignore NULL link keyLee, Chun-Yi1-0/+9
commit 33155c4aae5260475def6f7438e4e35564f4f3ba upstream. This change is used to relieve CVE-2020-26555. The description of the CVE: Bluetooth legacy BR/EDR PIN code pairing in Bluetooth Core Specification 1.0B through 5.2 may permit an unauthenticated nearby device to spoof the BD_ADDR of the peer device to complete pairing without knowledge of the PIN. [1] The detail of this attack is in IEEE paper: BlueMirror: Reflections on Bluetooth Pairing and Provisioning Protocols [2] It's a reflection attack. The paper mentioned that attacker can induce the attacked target to generate null link key (zero key) without PIN code. In BR/EDR, the key generation is actually handled in the controller which is below HCI. Thus, we can ignore null link key in the handler of "Link Key Notification event" to relieve the attack. A similar implementation also shows in btstack project. [3] v3: Drop the connection when null link key be detected. v2: - Used Link: tag instead of Closes: - Used bt_dev_dbg instead of BT_DBG - Added Fixes: tag Cc: stable@vger.kernel.org Fixes: 55ed8ca10f35 ("Bluetooth: Implement link key handling for the management interface") Link: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-26555 [1] Link: https://ieeexplore.ieee.org/abstract/document/9474325/authors#authors [2] Link: https://github.com/bluekitchen/btstack/blob/master/src/hci.c#L3722 [3] Signed-off-by: Lee, Chun-Yi <jlee@suse.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-30Bluetooth: L2CAP: Fix use-after-freeZhengping Jiang1-0/+5
[ Upstream commit f752a0b334bb95fe9b42ecb511e0864e2768046f ] Fix potential use-after-free in l2cap_le_command_rej. Signed-off-by: Zhengping Jiang <jiangzp@google.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_ready_cbSungwoo Kim1-0/+2
commit 1728137b33c00d5a2b5110ed7aafb42e7c32e4a1 upstream. l2cap_sock_release(sk) frees sk. However, sk's children are still alive and point to the already free'd sk's address. To fix this, l2cap_sock_release(sk) also cleans sk's children. ================================================================== BUG: KASAN: use-after-free in l2cap_sock_ready_cb+0xb7/0x100 net/bluetooth/l2cap_sock.c:1650 Read of size 8 at addr ffff888104617aa8 by task kworker/u3:0/276 CPU: 0 PID: 276 Comm: kworker/u3:0 Not tainted 6.2.0-00001-gef397bd4d5fb-dirty #59 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Workqueue: hci2 hci_rx_work Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x72/0x95 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:306 [inline] print_report+0x175/0x478 mm/kasan/report.c:417 kasan_report+0xb1/0x130 mm/kasan/report.c:517 l2cap_sock_ready_cb+0xb7/0x100 net/bluetooth/l2cap_sock.c:1650 l2cap_chan_ready+0x10e/0x1e0 net/bluetooth/l2cap_core.c:1386 l2cap_config_req+0x753/0x9f0 net/bluetooth/l2cap_core.c:4480 l2cap_bredr_sig_cmd net/bluetooth/l2cap_core.c:5739 [inline] l2cap_sig_channel net/bluetooth/l2cap_core.c:6509 [inline] l2cap_recv_frame+0xe2e/0x43c0 net/bluetooth/l2cap_core.c:7788 l2cap_recv_acldata+0x6ed/0x7e0 net/bluetooth/l2cap_core.c:8506 hci_acldata_packet net/bluetooth/hci_core.c:3813 [inline] hci_rx_work+0x66e/0xbc0 net/bluetooth/hci_core.c:4048 process_one_work+0x4ea/0x8e0 kernel/workqueue.c:2289 worker_thread+0x364/0x8e0 kernel/workqueue.c:2436 kthread+0x1b9/0x200 kernel/kthread.c:376 ret_from_fork+0x2c/0x50 arch/x86/entry/entry_64.S:308 </TASK> Allocated by task 288: kasan_save_stack+0x22/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x82/0x90 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:968 [inline] __kmalloc+0x5a/0x140 mm/slab_common.c:981 kmalloc include/linux/slab.h:584 [inline] sk_prot_alloc+0x113/0x1f0 net/core/sock.c:2040 sk_alloc+0x36/0x3c0 net/core/sock.c:2093 l2cap_sock_alloc.constprop.0+0x39/0x1c0 net/bluetooth/l2cap_sock.c:1852 l2cap_sock_create+0x10d/0x220 net/bluetooth/l2cap_sock.c:1898 bt_sock_create+0x183/0x290 net/bluetooth/af_bluetooth.c:132 __sock_create+0x226/0x380 net/socket.c:1518 sock_create net/socket.c:1569 [inline] __sys_socket_create net/socket.c:1606 [inline] __sys_socket_create net/socket.c:1591 [inline] __sys_socket+0x112/0x200 net/socket.c:1639 __do_sys_socket net/socket.c:1652 [inline] __se_sys_socket net/socket.c:1650 [inline] __x64_sys_socket+0x40/0x50 net/socket.c:1650 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3f/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc Freed by task 288: kasan_save_stack+0x22/0x50 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:523 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free mm/kasan/common.c:200 [inline] __kasan_slab_free+0x10a/0x190 mm/kasan/common.c:244 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook mm/slub.c:1807 [inline] slab_free mm/slub.c:3787 [inline] __kmem_cache_free+0x88/0x1f0 mm/slub.c:3800 sk_prot_free net/core/sock.c:2076 [inline] __sk_destruct+0x347/0x430 net/core/sock.c:2168 sk_destruct+0x9c/0xb0 net/core/sock.c:2183 __sk_free+0x82/0x220 net/core/sock.c:2194 sk_free+0x7c/0xa0 net/core/sock.c:2205 sock_put include/net/sock.h:1991 [inline] l2cap_sock_kill+0x256/0x2b0 net/bluetooth/l2cap_sock.c:1257 l2cap_sock_release+0x1a7/0x220 net/bluetooth/l2cap_sock.c:1428 __sock_release+0x80/0x150 net/socket.c:650 sock_close+0x19/0x30 net/socket.c:1368 __fput+0x17a/0x5c0 fs/file_table.c:320 task_work_run+0x132/0x1c0 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x113/0x120 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x21/0x50 kernel/entry/common.c:296 do_syscall_64+0x4c/0x90 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x72/0xdc The buggy address belongs to the object at ffff888104617800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 680 bytes inside of 1024-byte region [ffff888104617800, ffff888104617c00) The buggy address belongs to the physical page: page:00000000dbca6a80 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888104614000 pfn:0x104614 head:00000000dbca6a80 order:2 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0 flags: 0x200000000010200(slab|head|node=0|zone=2) raw: 0200000000010200 ffff888100041dc0 ffffea0004212c10 ffffea0004234b10 raw: ffff888104614000 0000000000080002 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888104617980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888104617a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888104617a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888104617b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888104617b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Ack: This bug is found by FuzzBT with a modified Syzkaller. Other contributors are Ruoyu Wu and Hui Peng. Signed-off-by: Sungwoo Kim <iam@sung-woo.kim> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-14Bluetooth: Fix use-after-free in hci_remove_ltk/hci_remove_irkLuiz Augusto von Dentz1-4/+4
commit c5d2b6fa26b5b8386a9cc902cdece3a46bef2bd2 upstream. Similar to commit 0f7d9b31ce7a ("netfilter: nf_tables: fix use-after-free in nft_set_catchall_destroy()"). We can not access k after kfree_rcu() call. Cc: stable@vger.kernel.org Signed-off-by: Min Li <lm0963hack@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-14Bluetooth: L2CAP: Add missing checks for invalid DCIDSungwoo Kim1-0/+9
[ Upstream commit 75767213f3d9b97f63694d02260b6a49a2271876 ] When receiving a connect response we should make sure that the DCID is within the valid range and that we don't already have another channel allocated for the same DCID. Missing checks may violate the specification (BLUETOOTH CORE SPECIFICATION Version 5.4 | Vol 3, Part A, Page 1046). Fixes: 40624183c202 ("Bluetooth: L2CAP: Add missing checks for invalid LE DCID") Signed-off-by: Sungwoo Kim <iam@sung-woo.kim> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-06-14Bluetooth: Fix l2cap_disconnect_req deadlockYing Hsu1-0/+4
[ Upstream commit 02c5ea5246a44d6ffde0fddebfc1d56188052976 ] L2CAP assumes that the locks conn->chan_lock and chan->lock are acquired in the order conn->chan_lock, chan->lock to avoid potential deadlock. For example, l2sock_shutdown acquires these locks in the order: mutex_lock(&conn->chan_lock) l2cap_chan_lock(chan) However, l2cap_disconnect_req acquires chan->lock in l2cap_get_chan_by_scid first and then acquires conn->chan_lock before calling l2cap_chan_del. This means that these locks are acquired in unexpected order, which leads to potential deadlock: l2cap_chan_lock(c) mutex_lock(&conn->chan_lock) This patch releases chan->lock before acquiring the conn_chan_lock to avoid the potential deadlock. Fixes: a2a9339e1c9d ("Bluetooth: L2CAP: Fix use-after-free in l2cap_disconnect_{req,rsp}") Signed-off-by: Ying Hsu <yinghsu@chromium.org> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-06-09bluetooth: Add cmd validity checks at the start of hci_sock_ioctl()Ruihan Li1-0/+28
commit 000c2fa2c144c499c881a101819cf1936a1f7cf2 upstream. Previously, channel open messages were always sent to monitors on the first ioctl() call for unbound HCI sockets, even if the command and arguments were completely invalid. This can leave an exploitable hole with the abuse of invalid ioctl calls. This commit hardens the ioctl processing logic by first checking if the command is valid, and immediately returning with an ENOIOCTLCMD error code if it is not. This ensures that ioctl calls with invalid commands are free of side effects, and increases the difficulty of further exploitation by forcing exploitation to find a way to pass a valid command first. Signed-off-by: Ruihan Li <lrh2000@pku.edu.cn> Co-developed-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Dragos-Marian Panait <dragos.panait@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-05-30Bluetooth: L2CAP: fix "bad unlock balance" in l2cap_disconnect_rspMin Li1-1/+0
[ Upstream commit 25e97f7b1866e6b8503be349eeea44bb52d661ce ] conn->chan_lock isn't acquired before l2cap_get_chan_by_scid, if l2cap_get_chan_by_scid returns NULL, then 'bad unlock balance' is triggered. Reported-by: syzbot+9519d6b5b79cf7787cf3@syzkaller.appspotmail.com Link: https://lore.kernel.org/all/000000000000894f5f05f95e9f4d@google.com/ Signed-off-by: Min Li <lm0963hack@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17bluetooth: Perform careful capability checks in hci_sock_ioctl()Ruihan Li1-1/+8
commit 25c150ac103a4ebeed0319994c742a90634ddf18 upstream. Previously, capability was checked using capable(), which verified that the caller of the ioctl system call had the required capability. In addition, the result of the check would be stored in the HCI_SOCK_TRUSTED flag, making it persistent for the socket. However, malicious programs can abuse this approach by deliberately sharing an HCI socket with a privileged task. The HCI socket will be marked as trusted when the privileged task occasionally makes an ioctl call. This problem can be solved by using sk_capable() to check capability, which ensures that not only the current task but also the socket opener has the specified capability, thus reducing the risk of privilege escalation through the previously identified vulnerability. Cc: stable@vger.kernel.org Fixes: f81f5b2db869 ("Bluetooth: Send control open and close messages for HCI raw sockets") Signed-off-by: Ruihan Li <lrh2000@pku.edu.cn> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20Bluetooth: Fix race condition in hidp_session_threadMin Li1-1/+1
commit c95930abd687fcd1aa040dc4fe90dff947916460 upstream. There is a potential race condition in hidp_session_thread that may lead to use-after-free. For instance, the timer is active while hidp_del_timer is called in hidp_session_thread(). After hidp_session_put, then 'session' will be freed, causing kernel panic when hidp_idle_timeout is running. The solution is to use del_timer_sync instead of del_timer. Here is the call trace: ? hidp_session_probe+0x780/0x780 call_timer_fn+0x2d/0x1e0 __run_timers.part.0+0x569/0x940 hidp_session_probe+0x780/0x780 call_timer_fn+0x1e0/0x1e0 ktime_get+0x5c/0xf0 lapic_next_deadline+0x2c/0x40 clockevents_program_event+0x205/0x320 run_timer_softirq+0xa9/0x1b0 __do_softirq+0x1b9/0x641 __irq_exit_rcu+0xdc/0x190 irq_exit_rcu+0xe/0x20 sysvec_apic_timer_interrupt+0xa1/0xc0 Cc: stable@vger.kernel.org Signed-off-by: Min Li <lm0963hack@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20Bluetooth: L2CAP: Fix use-after-free in l2cap_disconnect_{req,rsp}Luiz Augusto von Dentz1-18/+6
commit a2a9339e1c9deb7e1e079e12e27a0265aea8421a upstream. Similar to commit d0be8347c623 ("Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put"), just use l2cap_chan_hold_unless_zero to prevent referencing a channel that is about to be destroyed. Cc: stable@kernel.org Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Min Li <lm0963hack@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-11Bluetooth: hci_sock: purge socket queues in the destruct() callbackNguyen Dinh Phi1-4/+7
commit 709fca500067524381e28a5f481882930eebac88 upstream. The receive path may take the socket right before hci_sock_release(), but it may enqueue the packets to the socket queues after the call to skb_queue_purge(), therefore the socket can be destroyed without clear its queues completely. Moving these skb_queue_purge() to the hci_sock_destruct() will fix this issue, because nothing is referencing the socket at this point. Signed-off-by: Nguyen Dinh Phi <phind.uet@gmail.com> Reported-by: syzbot+4c4ffd1e1094dae61035@syzkaller.appspotmail.com Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-11Bluetooth: L2CAP: Fix potential user-after-freeLuiz Augusto von Dentz2-24/+8
[ Upstream commit df5703348813235874d851934e957c3723d71644 ] This fixes all instances of which requires to allocate a buffer calling alloc_skb which may release the chan lock and reacquire later which makes it possible that the chan is disconnected in the meantime. Fixes: a6a5568c03c4 ("Bluetooth: Lock the L2CAP channel when sending") Reported-by: Alexander Coffin <alex.coffin@matician.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-06Bluetooth: hci_sync: cancel cmd_timer if hci_open failedArchie Pusaka1-0/+1
commit 97dfaf073f5881c624856ef293be307b6166115c upstream. If a command is already sent, we take care of freeing it, but we also need to cancel the timeout as well. Signed-off-by: Archie Pusaka <apusaka@chromium.org> Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@google.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18Bluetooth: RFCOMM: don't call kfree_skb() under spin_lock_irqsave()Yang Yingliang1-1/+1
[ Upstream commit 0ba18967d4544955b2eff2fbc4f2a8750c4df90a ] It is not allowed to call kfree_skb() from hardware interrupt context or with interrupts being disabled. So replace kfree_skb() with dev_kfree_skb_irq() under spin_lock_irqsave(). Fixes: 81be03e026dc ("Bluetooth: RFCOMM: Replace use of memcpy_from_msg with bt_skb_sendmmsg") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18Bluetooth: hci_core: don't call kfree_skb() under spin_lock_irqsave()Yang Yingliang1-1/+1
[ Upstream commit 39c1eb6fcbae8ce9bb71b2ac5cb609355a2b181b ] It is not allowed to call kfree_skb() from hardware interrupt context or with interrupts being disabled. So replace kfree_skb() with dev_kfree_skb_irq() under spin_lock_irqsave(). Fixes: 9238f36a5a50 ("Bluetooth: Add request cmd_complete and cmd_status functions") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18Bluetooth: L2CAP: Fix u8 overflowSungwoo Kim1-1/+2
[ Upstream commit bcd70260ef56e0aee8a4fc6cd214a419900b0765 ] By keep sending L2CAP_CONF_REQ packets, chan->num_conf_rsp increases multiple times and eventually it will wrap around the maximum number (i.e., 255). This patch prevents this by adding a boundary check with L2CAP_MAX_CONF_RSP Btmon log: Bluetooth monitor ver 5.64 = Note: Linux version 6.1.0-rc2 (x86_64) 0.264594 = Note: Bluetooth subsystem version 2.22 0.264636 @ MGMT Open: btmon (privileged) version 1.22 {0x0001} 0.272191 = New Index: 00:00:00:00:00:00 (Primary,Virtual,hci0) [hci0] 13.877604 @ RAW Open: 9496 (privileged) version 2.22 {0x0002} 13.890741 = Open Index: 00:00:00:00:00:00 [hci0] 13.900426 (...) > ACL Data RX: Handle 200 flags 0x00 dlen 1033 #32 [hci0] 14.273106 invalid packet size (12 != 1033) 08 00 01 00 02 01 04 00 01 10 ff ff ............ > ACL Data RX: Handle 200 flags 0x00 dlen 1547 #33 [hci0] 14.273561 invalid packet size (14 != 1547) 0a 00 01 00 04 01 06 00 40 00 00 00 00 00 ........@..... > ACL Data RX: Handle 200 flags 0x00 dlen 2061 #34 [hci0] 14.274390 invalid packet size (16 != 2061) 0c 00 01 00 04 01 08 00 40 00 00 00 00 00 00 04 ........@....... > ACL Data RX: Handle 200 flags 0x00 dlen 2061 #35 [hci0] 14.274932 invalid packet size (16 != 2061) 0c 00 01 00 04 01 08 00 40 00 00 00 07 00 03 00 ........@....... = bluetoothd: Bluetooth daemon 5.43 14.401828 > ACL Data RX: Handle 200 flags 0x00 dlen 1033 #36 [hci0] 14.275753 invalid packet size (12 != 1033) 08 00 01 00 04 01 04 00 40 00 00 00 ........@... Signed-off-by: Sungwoo Kim <iam@sung-woo.kim> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-14Bluetooth: Fix not cleanup led when bt_init failsChen Zhongjin1-1/+3
[ Upstream commit 2f3957c7eb4e07df944169a3e50a4d6790e1c744 ] bt_init() calls bt_leds_init() to register led, but if it fails later, bt_leds_cleanup() is not called to unregister it. This can cause panic if the argument "bluetooth-power" in text is freed and then another led_trigger_register() tries to access it: BUG: unable to handle page fault for address: ffffffffc06d3bc0 RIP: 0010:strcmp+0xc/0x30 Call Trace: <TASK> led_trigger_register+0x10d/0x4f0 led_trigger_register_simple+0x7d/0x100 bt_init+0x39/0xf7 [bluetooth] do_one_initcall+0xd0/0x4e0 Fixes: e64c97b53bc6 ("Bluetooth: Add combined LED trigger for controller power") Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-14Bluetooth: 6LoWPAN: add missing hci_dev_put() in get_l2cap_conn()Wang ShaoBo1-0/+1
[ Upstream commit 747da1308bdd5021409974f9180f0d8ece53d142 ] hci_get_route() takes reference, we should use hci_dev_put() to release it when not need anymore. Fixes: 6b8d4a6a0314 ("Bluetooth: 6LoWPAN: Use connected oriented channel instead of fixed one") Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-08Bluetooth: L2CAP: Fix accepting connection request for invalid SPSMLuiz Augusto von Dentz1-0/+13
commit 711f8c3fb3db61897080468586b970c87c61d9e4 upstream. The Bluetooth spec states that the valid range for SPSM is from 0x0001-0x00ff so it is invalid to accept values outside of this range: BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A page 1059: Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges CVE: CVE-2022-42896 CC: stable@vger.kernel.org Reported-by: Tamás Koczka <poprdi@google.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Reviewed-by: Tedd Ho-Jeong An <tedd.an@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-25Bluetooth: L2CAP: Fix l2cap_global_chan_by_psmLuiz Augusto von Dentz1-1/+1
[ Upstream commit f937b758a188d6fd328a81367087eddbb2fce50f ] l2cap_global_chan_by_psm shall not return fixed channels as they are not meant to be connected by (S)PSM. Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Reviewed-by: Tedd Ho-Jeong An <tedd.an@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10Bluetooth: L2CAP: Fix attempting to access uninitialized memoryLuiz Augusto von Dentz1-1/+2
commit b1a2cd50c0357f243b7435a732b4e62ba3157a2e upstream. On l2cap_parse_conf_req the variable efs is only initialized if remote_efs has been set. CVE: CVE-2022-42895 CC: stable@vger.kernel.org Reported-by: Tamás Koczka <poprdi@google.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Reviewed-by: Tedd Ho-Jeong An <tedd.an@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-11-10Bluetooth: L2CAP: fix use-after-free in l2cap_conn_del()Zhengchao Shao1-0/+1
[ Upstream commit 0d0e2d032811280b927650ff3c15fe5020e82533 ] When l2cap_recv_frame() is invoked to receive data, and the cid is L2CAP_CID_A2MP, if the channel does not exist, it will create a channel. However, after a channel is created, the hold operation of the channel is not performed. In this case, the value of channel reference counting is 1. As a result, after hci_error_reset() is triggered, l2cap_conn_del() invokes the close hook function of A2MP to release the channel. Then l2cap_chan_unlock(chan) will trigger UAF issue. The process is as follows: Receive data: l2cap_data_channel() a2mp_channel_create() --->channel ref is 2 l2cap_chan_put() --->channel ref is 1 Triger event: hci_error_reset() hci_dev_do_close() ... l2cap_disconn_cfm() l2cap_conn_del() l2cap_chan_hold() --->channel ref is 2 l2cap_chan_del() --->channel ref is 1 a2mp_chan_close_cb() --->channel ref is 0, release channel l2cap_chan_unlock() --->UAF of channel The detailed Call Trace is as follows: BUG: KASAN: use-after-free in __mutex_unlock_slowpath+0xa6/0x5e0 Read of size 8 at addr ffff8880160664b8 by task kworker/u11:1/7593 Workqueue: hci0 hci_error_reset Call Trace: <TASK> dump_stack_lvl+0xcd/0x134 print_report.cold+0x2ba/0x719 kasan_report+0xb1/0x1e0 kasan_check_range+0x140/0x190 __mutex_unlock_slowpath+0xa6/0x5e0 l2cap_conn_del+0x404/0x7b0 l2cap_disconn_cfm+0x8c/0xc0 hci_conn_hash_flush+0x11f/0x260 hci_dev_close_sync+0x5f5/0x11f0 hci_dev_do_close+0x2d/0x70 hci_error_reset+0x9e/0x140 process_one_work+0x98a/0x1620 worker_thread+0x665/0x1080 kthread+0x2e4/0x3a0 ret_from_fork+0x1f/0x30 </TASK> Allocated by task 7593: kasan_save_stack+0x1e/0x40 __kasan_kmalloc+0xa9/0xd0 l2cap_chan_create+0x40/0x930 amp_mgr_create+0x96/0x990 a2mp_channel_create+0x7d/0x150 l2cap_recv_frame+0x51b8/0x9a70 l2cap_recv_acldata+0xaa3/0xc00 hci_rx_work+0x702/0x1220 process_one_work+0x98a/0x1620 worker_thread+0x665/0x1080 kthread+0x2e4/0x3a0 ret_from_fork+0x1f/0x30 Freed by task 7593: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_set_free_info+0x20/0x30 ____kasan_slab_free+0x167/0x1c0 slab_free_freelist_hook+0x89/0x1c0 kfree+0xe2/0x580 l2cap_chan_put+0x22a/0x2d0 l2cap_conn_del+0x3fc/0x7b0 l2cap_disconn_cfm+0x8c/0xc0 hci_conn_hash_flush+0x11f/0x260 hci_dev_close_sync+0x5f5/0x11f0 hci_dev_do_close+0x2d/0x70 hci_error_reset+0x9e/0x140 process_one_work+0x98a/0x1620 worker_thread+0x665/0x1080 kthread+0x2e4/0x3a0 ret_from_fork+0x1f/0x30 Last potentially related work creation: kasan_save_stack+0x1e/0x40 __kasan_record_aux_stack+0xbe/0xd0 call_rcu+0x99/0x740 netlink_release+0xe6a/0x1cf0 __sock_release+0xcd/0x280 sock_close+0x18/0x20 __fput+0x27c/0xa90 task_work_run+0xdd/0x1a0 exit_to_user_mode_prepare+0x23c/0x250 syscall_exit_to_user_mode+0x19/0x50 do_syscall_64+0x42/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Second to last potentially related work creation: kasan_save_stack+0x1e/0x40 __kasan_record_aux_stack+0xbe/0xd0 call_rcu+0x99/0x740 netlink_release+0xe6a/0x1cf0 __sock_release+0xcd/0x280 sock_close+0x18/0x20 __fput+0x27c/0xa90 task_work_run+0xdd/0x1a0 exit_to_user_mode_prepare+0x23c/0x250 syscall_exit_to_user_mode+0x19/0x50 do_syscall_64+0x42/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Fixes: d0be8347c623 ("Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put") Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10Bluetooth: L2CAP: Fix use-after-free caused by l2cap_reassemble_sduMaxim Mikityanskiy1-7/+41
[ Upstream commit 3aff8aaca4e36dc8b17eaa011684881a80238966 ] Fix the race condition between the following two flows that run in parallel: 1. l2cap_reassemble_sdu -> chan->ops->recv (l2cap_sock_recv_cb) -> __sock_queue_rcv_skb. 2. bt_sock_recvmsg -> skb_recv_datagram, skb_free_datagram. An SKB can be queued by the first flow and immediately dequeued and freed by the second flow, therefore the callers of l2cap_reassemble_sdu can't use the SKB after that function returns. However, some places continue accessing struct l2cap_ctrl that resides in the SKB's CB for a short time after l2cap_reassemble_sdu returns, leading to a use-after-free condition (the stack trace is below, line numbers for kernel 5.19.8). Fix it by keeping a local copy of struct l2cap_ctrl. BUG: KASAN: use-after-free in l2cap_rx_state_recv (net/bluetooth/l2cap_core.c:6906) bluetooth Read of size 1 at addr ffff88812025f2f0 by task kworker/u17:3/43169 Workqueue: hci0 hci_rx_work [bluetooth] Call Trace: <TASK> dump_stack_lvl (lib/dump_stack.c:107 (discriminator 4)) print_report.cold (mm/kasan/report.c:314 mm/kasan/report.c:429) ? l2cap_rx_state_recv (net/bluetooth/l2cap_core.c:6906) bluetooth kasan_report (mm/kasan/report.c:162 mm/kasan/report.c:493) ? l2cap_rx_state_recv (net/bluetooth/l2cap_core.c:6906) bluetooth l2cap_rx_state_recv (net/bluetooth/l2cap_core.c:6906) bluetooth l2cap_rx (net/bluetooth/l2cap_core.c:7236 net/bluetooth/l2cap_core.c:7271) bluetooth ret_from_fork (arch/x86/entry/entry_64.S:306) </TASK> Allocated by task 43169: kasan_save_stack (mm/kasan/common.c:39) __kasan_slab_alloc (mm/kasan/common.c:45 mm/kasan/common.c:436 mm/kasan/common.c:469) kmem_cache_alloc_node (mm/slab.h:750 mm/slub.c:3243 mm/slub.c:3293) __alloc_skb (net/core/skbuff.c:414) l2cap_recv_frag (./include/net/bluetooth/bluetooth.h:425 net/bluetooth/l2cap_core.c:8329) bluetooth l2cap_recv_acldata (net/bluetooth/l2cap_core.c:8442) bluetooth hci_rx_work (net/bluetooth/hci_core.c:3642 net/bluetooth/hci_core.c:3832) bluetooth process_one_work (kernel/workqueue.c:2289) worker_thread (./include/linux/list.h:292 kernel/workqueue.c:2437) kthread (kernel/kthread.c:376) ret_from_fork (arch/x86/entry/entry_64.S:306) Freed by task 27920: kasan_save_stack (mm/kasan/common.c:39) kasan_set_track (mm/kasan/common.c:45) kasan_set_free_info (mm/kasan/generic.c:372) ____kasan_slab_free (mm/kasan/common.c:368 mm/kasan/common.c:328) slab_free_freelist_hook (mm/slub.c:1780) kmem_cache_free (mm/slub.c:3536 mm/slub.c:3553) skb_free_datagram (./include/net/sock.h:1578 ./include/net/sock.h:1639 net/core/datagram.c:323) bt_sock_recvmsg (net/bluetooth/af_bluetooth.c:295) bluetooth l2cap_sock_recvmsg (net/bluetooth/l2cap_sock.c:1212) bluetooth sock_read_iter (net/socket.c:1087) new_sync_read (./include/linux/fs.h:2052 fs/read_write.c:401) vfs_read (fs/read_write.c:482) ksys_read (fs/read_write.c:620) do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120) Link: https://lore.kernel.org/linux-bluetooth/CAKErNvoqga1WcmoR3-0875esY6TVWFQDandbVZncSiuGPBQXLA@mail.gmail.com/T/#u Fixes: d2a7ac5d5d3a ("Bluetooth: Add the ERTM receive state machine") Fixes: 4b51dae96731 ("Bluetooth: Add streaming mode receive and incoming packet classifier") Signed-off-by: Maxim Mikityanskiy <maxtram95@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26Bluetooth: L2CAP: Fix user-after-freeLuiz Augusto von Dentz1-0/+7
[ Upstream commit 35fcbc4243aad7e7d020b7c1dfb14bb888b20a4f ] This uses l2cap_chan_hold_unless_zero() after calling __l2cap_get_chan_blah() to prevent the following trace: Bluetooth: l2cap_core.c:static void l2cap_chan_destroy(struct kref *kref) Bluetooth: chan 0000000023c4974d Bluetooth: parent 00000000ae861c08 ================================================================== BUG: KASAN: use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:191 [inline] BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:671 [inline] BUG: KASAN: use-after-free in __mutex_lock+0x278/0x400 kernel/locking/mutex.c:729 Read of size 8 at addr ffff888006a49b08 by task kworker/u3:2/389 Link: https://lore.kernel.org/lkml/20220622082716.478486-1-lee.jones@linaro.org Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sungwoo Kim <iam@sung-woo.kim> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26Bluetooth: hci_sysfs: Fix attempting to call device_add multiple timesLuiz Augusto von Dentz1-0/+3
[ Upstream commit 448a496f760664d3e2e79466aa1787e6abc922b5 ] device_add shall not be called multiple times as stated in its documentation: 'Do not call this routine or device_register() more than once for any device structure' Syzkaller reports a bug as follows [1]: ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:33! invalid opcode: 0000 [#1] PREEMPT SMP KASAN [...] Call Trace: <TASK> __list_add include/linux/list.h:69 [inline] list_add_tail include/linux/list.h:102 [inline] kobj_kset_join lib/kobject.c:164 [inline] kobject_add_internal+0x18f/0x8f0 lib/kobject.c:214 kobject_add_varg lib/kobject.c:358 [inline] kobject_add+0x150/0x1c0 lib/kobject.c:410 device_add+0x368/0x1e90 drivers/base/core.c:3452 hci_conn_add_sysfs+0x9b/0x1b0 net/bluetooth/hci_sysfs.c:53 hci_le_cis_estabilished_evt+0x57c/0xae0 net/bluetooth/hci_event.c:6799 hci_le_meta_evt+0x2b8/0x510 net/bluetooth/hci_event.c:7110 hci_event_func net/bluetooth/hci_event.c:7440 [inline] hci_event_packet+0x63d/0xfd0 net/bluetooth/hci_event.c:7495 hci_rx_work+0xae7/0x1230 net/bluetooth/hci_core.c:4007 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 </TASK> Link: https://syzkaller.appspot.com/bug?id=da3246e2d33afdb92d66bc166a0934c5b146404a Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Tested-by: Hawkins Jiawei <yin31149@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-26Bluetooth: L2CAP: initialize delayed works at l2cap_chan_create()Tetsuo Handa1-4/+6
[ Upstream commit 2d2cb3066f2c90cd8ca540b36ba7a55e7f2406e0 ] syzbot is reporting cancel_delayed_work() without INIT_DELAYED_WORK() at l2cap_chan_del() [1], for CONF_NOT_COMPLETE flag (which meant to prevent l2cap_chan_del() from calling cancel_delayed_work()) is cleared by timer which fires before l2cap_chan_del() is called by closing file descriptor created by socket(AF_BLUETOOTH, SOCK_STREAM, BTPROTO_L2CAP). l2cap_bredr_sig_cmd(L2CAP_CONF_REQ) and l2cap_bredr_sig_cmd(L2CAP_CONF_RSP) are calling l2cap_ertm_init(chan), and they call l2cap_chan_ready() (which clears CONF_NOT_COMPLETE flag) only when l2cap_ertm_init(chan) succeeded. l2cap_sock_init() does not call l2cap_ertm_init(chan), and it instead sets CONF_NOT_COMPLETE flag by calling l2cap_chan_set_defaults(). However, when connect() is requested, "command 0x0409 tx timeout" happens after 2 seconds from connect() request, and CONF_NOT_COMPLETE flag is cleared after 4 seconds from connect() request, for l2cap_conn_start() from l2cap_info_timeout() callback scheduled by schedule_delayed_work(&conn->info_timer, L2CAP_INFO_TIMEOUT); in l2cap_connect() is calling l2cap_chan_ready(). Fix this problem by initializing delayed works used by L2CAP_MODE_ERTM mode as soon as l2cap_chan_create() allocates a channel, like I did in commit be8597239379f0f5 ("Bluetooth: initialize skb_queue_head at l2cap_chan_create()"). Link: https://syzkaller.appspot.com/bug?extid=83672956c7aa6af698b3 [1] Reported-by: syzbot <syzbot+83672956c7aa6af698b3@syzkaller.appspotmail.com> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-05Bluetooth: L2CAP: Fix build errors in some archsLuiz Augusto von Dentz1-5/+5
commit b840304fb46cdf7012722f456bce06f151b3e81b upstream. This attempts to fix the follow errors: In function 'memcmp', inlined from 'bacmp' at ./include/net/bluetooth/bluetooth.h:347:9, inlined from 'l2cap_global_chan_by_psm' at net/bluetooth/l2cap_core.c:2003:15: ./include/linux/fortify-string.h:44:33: error: '__builtin_memcmp' specified bound 6 exceeds source size 0 [-Werror=stringop-overread] 44 | #define __underlying_memcmp __builtin_memcmp | ^ ./include/linux/fortify-string.h:420:16: note: in expansion of macro '__underlying_memcmp' 420 | return __underlying_memcmp(p, q, size); | ^~~~~~~~~~~~~~~~~~~ In function 'memcmp', inlined from 'bacmp' at ./include/net/bluetooth/bluetooth.h:347:9, inlined from 'l2cap_global_chan_by_psm' at net/bluetooth/l2cap_core.c:2004:15: ./include/linux/fortify-string.h:44:33: error: '__builtin_memcmp' specified bound 6 exceeds source size 0 [-Werror=stringop-overread] 44 | #define __underlying_memcmp __builtin_memcmp | ^ ./include/linux/fortify-string.h:420:16: note: in expansion of macro '__underlying_memcmp' 420 | return __underlying_memcmp(p, q, size); | ^~~~~~~~~~~~~~~~~~~ Fixes: 332f1795ca20 ("Bluetooth: L2CAP: Fix l2cap_global_chan_by_psm regression") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25Bluetooth: L2CAP: Fix l2cap_global_chan_by_psm regressionLuiz Augusto von Dentz1-7/+6
commit 332f1795ca202489c665a75e62e18ff6284de077 upstream. The patch d0be8347c623: "Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put" from Jul 21, 2022, leads to the following Smatch static checker warning: net/bluetooth/l2cap_core.c:1977 l2cap_global_chan_by_psm() error: we previously assumed 'c' could be null (see line 1996) Fixes: d0be8347c623 ("Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_put") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-11Bluetooth: L2CAP: Fix use-after-free caused by l2cap_chan_putLuiz Augusto von Dentz1-13/+48
commit d0be8347c623e0ac4202a1d4e0373882821f56b0 upstream. This fixes the following trace which is caused by hci_rx_work starting up *after* the final channel reference has been put() during sock_close() but *before* the references to the channel have been destroyed, so instead the code now rely on kref_get_unless_zero/l2cap_chan_hold_unless_zero to prevent referencing a channel that is about to be destroyed. refcount_t: increment on 0; use-after-free. BUG: KASAN: use-after-free in refcount_dec_and_test+0x20/0xd0 Read of size 4 at addr ffffffc114f5bf18 by task kworker/u17:14/705 CPU: 4 PID: 705 Comm: kworker/u17:14 Tainted: G S W 4.14.234-00003-g1fb6d0bd49a4-dirty #28 Hardware name: Qualcomm Technologies, Inc. SM8150 V2 PM8150 Google Inc. MSM sm8150 Flame DVT (DT) Workqueue: hci0 hci_rx_work Call trace: dump_backtrace+0x0/0x378 show_stack+0x20/0x2c dump_stack+0x124/0x148 print_address_description+0x80/0x2e8 __kasan_report+0x168/0x188 kasan_report+0x10/0x18 __asan_load4+0x84/0x8c refcount_dec_and_test+0x20/0xd0 l2cap_chan_put+0x48/0x12c l2cap_recv_frame+0x4770/0x6550 l2cap_recv_acldata+0x44c/0x7a4 hci_acldata_packet+0x100/0x188 hci_rx_work+0x178/0x23c process_one_work+0x35c/0x95c worker_thread+0x4cc/0x960 kthread+0x1a8/0x1c4 ret_from_fork+0x10/0x18 Cc: stable@kernel.org Reported-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Tested-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29Bluetooth: SCO: Fix sco_send_frame returning skb->lenLuiz Augusto von Dentz1-4/+6
commit 037ce005af6b8a3e40ee07c6e9266c8997e6a4d6 upstream. The skb in modified by hci_send_sco which pushes SCO headers thus changing skb->len causing sco_sock_sendmsg to fail. Fixes: 0771cbb3b97d ("Bluetooth: SCO: Replace use of memcpy_from_msg with bt_skb_sendmsg") Tested-by: Tedd Ho-Jeong An <tedd.an@intel.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29Bluetooth: Fix passing NULL to PTR_ERRLuiz Augusto von Dentz2-2/+2
commit 266191aa8d14b84958aaeb5e96ee4e97839e3d87 upstream. Passing NULL to PTR_ERR will result in 0 (success), also since the likes of bt_skb_sendmsg does never return NULL it is safe to replace the instances of IS_ERR_OR_NULL with IS_ERR when checking its return. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Tested-by: Tedd Ho-Jeong An <tedd.an@intel.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29Bluetooth: RFCOMM: Replace use of memcpy_from_msg with bt_skb_sendmmsgLuiz Augusto von Dentz2-43/+53
commit 81be03e026dc0c16dc1c64e088b2a53b73caa895 upstream. This makes use of bt_skb_sendmmsg instead using memcpy_from_msg which is not considered safe to be used when lock_sock is held. Also make rfcomm_dlc_send handle skb with fragments and queue them all atomically. Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29Bluetooth: SCO: Replace use of memcpy_from_msg with bt_skb_sendmsgLuiz Augusto von Dentz1-23/+11
commit 0771cbb3b97d3c1d68eecd7f00055f599954c34e upstream. This makes use of bt_skb_sendmsg instead of allocating a different buffer to be used with memcpy_from_msg which cause one extra copy. Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-14Bluetooth: fix dangling sco_conn and use-after-free in sco_sock_timeoutYing Hsu1-8/+13
[ Upstream commit 7aa1e7d15f8a5b65f67bacb100d8fc033b21efa2 ] Connecting the same socket twice consecutively in sco_sock_connect() could lead to a race condition where two sco_conn objects are created but only one is associated with the socket. If the socket is closed before the SCO connection is established, the timer associated with the dangling sco_conn object won't be canceled. As the sock object is being freed, the use-after-free problem happens when the timer callback function sco_sock_timeout() accesses the socket. Here's the call trace: dump_stack+0x107/0x163 ? refcount_inc+0x1c/ print_address_description.constprop.0+0x1c/0x47e ? refcount_inc+0x1c/0x7b kasan_report+0x13a/0x173 ? refcount_inc+0x1c/0x7b check_memory_region+0x132/0x139 refcount_inc+0x1c/0x7b sco_sock_timeout+0xb2/0x1ba process_one_work+0x739/0xbd1 ? cancel_delayed_work+0x13f/0x13f ? __raw_spin_lock_init+0xf0/0xf0 ? to_kthread+0x59/0x85 worker_thread+0x593/0x70e kthread+0x346/0x35a ? drain_workqueue+0x31a/0x31a ? kthread_bind+0x4b/0x4b ret_from_fork+0x1f/0x30 Link: https://syzkaller.appspot.com/bug?extid=2bef95d3ab4daa10155b Reported-by: syzbot+2bef95d3ab4daa10155b@syzkaller.appspotmail.com Fixes: e1dee2c1de2b ("Bluetooth: fix repeated calls to sco_sock_kill") Signed-off-by: Ying Hsu <yinghsu@chromium.org> Reviewed-by: Joseph Hwang <josephsih@chromium.org> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-15Bluetooth: Fix the creation of hdev->nameItay Iellin1-3/+3
commit 103a2f3255a95991252f8f13375c3a96a75011cd upstream. Set a size limit of 8 bytes of the written buffer to "hdev->name" including the terminating null byte, as the size of "hdev->name" is 8 bytes. If an id value which is greater than 9999 is allocated, then the "snprintf(hdev->name, sizeof(hdev->name), "hci%d", id)" function call would lead to a truncation of the id value in decimal notation. Set an explicit maximum id parameter in the id allocation function call. The id allocation function defines the maximum allocated id value as the maximum id parameter value minus one. Therefore, HCI_MAX_ID is defined as 10000. Signed-off-by: Itay Iellin <ieitayie@gmail.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15Bluetooth: Fix use after free in hci_send_aclLuiz Augusto von Dentz1-1/+2
[ Upstream commit f63d24baff787e13b723d86fe036f84bdbc35045 ] This fixes the following trace caused by receiving HCI_EV_DISCONN_PHY_LINK_COMPLETE which does call hci_conn_del without first checking if conn->type is in fact AMP_LINK and in case it is do properly cleanup upper layers with hci_disconn_cfm: ================================================================== BUG: KASAN: use-after-free in hci_send_acl+0xaba/0xc50 Read of size 8 at addr ffff88800e404818 by task bluetoothd/142 CPU: 0 PID: 142 Comm: bluetoothd Not tainted 5.17.0-rc5-00006-gda4022eeac1a #7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x45/0x59 print_address_description.constprop.0+0x1f/0x150 kasan_report.cold+0x7f/0x11b hci_send_acl+0xaba/0xc50 l2cap_do_send+0x23f/0x3d0 l2cap_chan_send+0xc06/0x2cc0 l2cap_sock_sendmsg+0x201/0x2b0 sock_sendmsg+0xdc/0x110 sock_write_iter+0x20f/0x370 do_iter_readv_writev+0x343/0x690 do_iter_write+0x132/0x640 vfs_writev+0x198/0x570 do_writev+0x202/0x280 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RSP: 002b:00007ffce8a099b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 Code: 0f 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 14 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10 RDX: 0000000000000001 RSI: 00007ffce8a099e0 RDI: 0000000000000015 RAX: ffffffffffffffda RBX: 00007ffce8a099e0 RCX: 00007f788fc3cf77 R10: 00007ffce8af7080 R11: 0000000000000246 R12: 000055e4ccf75580 RBP: 0000000000000015 R08: 0000000000000002 R09: 0000000000000001 </TASK> R13: 000055e4ccf754a0 R14: 000055e4ccf75cd0 R15: 000055e4ccf4a6b0 Allocated by task 45: kasan_save_stack+0x1e/0x40 __kasan_kmalloc+0x81/0xa0 hci_chan_create+0x9a/0x2f0 l2cap_conn_add.part.0+0x1a/0xdc0 l2cap_connect_cfm+0x236/0x1000 le_conn_complete_evt+0x15a7/0x1db0 hci_le_conn_complete_evt+0x226/0x2c0 hci_le_meta_evt+0x247/0x450 hci_event_packet+0x61b/0xe90 hci_rx_work+0x4d5/0xc50 process_one_work+0x8fb/0x15a0 worker_thread+0x576/0x1240 kthread+0x29d/0x340 ret_from_fork+0x1f/0x30 Freed by task 45: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_set_free_info+0x20/0x30 __kasan_slab_free+0xfb/0x130 kfree+0xac/0x350 hci_conn_cleanup+0x101/0x6a0 hci_conn_del+0x27e/0x6c0 hci_disconn_phylink_complete_evt+0xe0/0x120 hci_event_packet+0x812/0xe90 hci_rx_work+0x4d5/0xc50 process_one_work+0x8fb/0x15a0 worker_thread+0x576/0x1240 kthread+0x29d/0x340 ret_from_fork+0x1f/0x30 The buggy address belongs to the object at ffff88800c0f0500 The buggy address is located 24 bytes inside of which belongs to the cache kmalloc-128 of size 128 The buggy address belongs to the page: 128-byte region [ffff88800c0f0500, ffff88800c0f0580) flags: 0x100000000000200(slab|node=0|zone=1) page:00000000fe45cd86 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xc0f0 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 raw: 0100000000000200 ffffea00003a2c80 dead000000000004 ffff8880078418c0 page dumped because: kasan: bad access detected ffff88800c0f0400: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc Memory state around the buggy address: >ffff88800c0f0500: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88800c0f0480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88800c0f0580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ================================================================== ffff88800c0f0600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Reported-by: Sönke Huster <soenke.huster@eknoes.de> Tested-by: Sönke Huster <soenke.huster@eknoes.de> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-08Bluetooth: refactor malicious adv data checkBrian Gix1-5/+5
commit 899663be5e75dc0174dc8bda0b5e6826edf0b29a upstream. Check for out-of-bound read was being performed at the end of while num_reports loop, and would fill journal with false positives. Added check to beginning of loop processing so that it doesn't get checked after ptr has been advanced. Signed-off-by: Brian Gix <brian.gix@intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Cc: syphyr <syphyr@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-27Bluetooth: Fix debugfs entry leak in hci_register_dev()Wei Yongjun1-0/+1
[ Upstream commit 5a4bb6a8e981d3d0d492aa38412ee80b21033177 ] Fault injection test report debugfs entry leak as follows: debugfs: Directory 'hci0' with parent 'bluetooth' already present! When register_pm_notifier() failed in hci_register_dev(), the debugfs create by debugfs_create_dir() do not removed in the error handing path. Add the remove debugfs code to fix it. Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27Bluetooth: stop proccessing malicious adv dataPavel Skripkin1-1/+7
[ Upstream commit 3a56ef719f0b9682afb8a86d64b2399e36faa4e6 ] Syzbot reported slab-out-of-bounds read in hci_le_adv_report_evt(). The problem was in missing validaion check. We should check if data is not malicious and we can read next data block. If we won't check ptr validness, code can read a way beyond skb->end and it can cause problems, of course. Fixes: e95beb414168 ("Bluetooth: hci_le_adv_report_evt code refactoring") Reported-and-tested-by: syzbot+e3fcb9c4f3c2a931dc40@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-01-27Bluetooth: cmtp: fix possible panic when cmtp_init_sockets() failsWang Hai1-3/+1
[ Upstream commit 2a7ca7459d905febf519163bd9e3eed894de6bb7 ] I got a kernel BUG report when doing fault injection test: ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:45! ... RIP: 0010:__list_del_entry_valid.cold+0x12/0x4d ... Call Trace: proto_unregister+0x83/0x220 cmtp_cleanup_sockets+0x37/0x40 [cmtp] cmtp_exit+0xe/0x1f [cmtp] do_syscall_64+0x35/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae If cmtp_init_sockets() in cmtp_init() fails, cmtp_init() still returns success. This will cause a kernel bug when accessing uncreated ctmp related data when the module exits. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Wang Hai <wanghai38@huawei.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Sasha Levin <sashal@kernel.org>