| From bippy-1.1.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2022-49909: Bluetooth: L2CAP: fix use-after-free in l2cap_conn_del() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| Bluetooth: L2CAP: fix use-after-free in l2cap_conn_del() |
| |
| 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 |
| |
| The Linux kernel CVE team has assigned CVE-2022-49909 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.9.326 with commit d255c861e268ba342e855244639a15f12d7a0bf2 and fixed in 4.9.333 with commit db4a0783ed78beb2ebaa32f5f785bfd79c580689 |
| Issue introduced in 4.14.291 with commit 5bb395334392891dffae5a0e8f37dbe1d70496c9 and fixed in 4.14.299 with commit 17c6164854f8bb80bf76f32b2c2f199c16b53703 |
| Issue introduced in 4.19.255 with commit bbd1fdb0e1adf827997a93bf108f20ede038e56e and fixed in 4.19.265 with commit 7f7bfdd9a9af3b12c33d9da9a012e7f4d5c91f4b |
| Issue introduced in 5.4.209 with commit 098e07ef0059296e710a801cdbd74b59016e6624 and fixed in 5.4.224 with commit c1f594dddd9ffd747c39f49cc5b67a9b7677d2ab |
| Issue introduced in 5.10.135 with commit de5d4654ac6c22b1be756fdf7db18471e7df01ea and fixed in 5.10.154 with commit d9ec6e2fbd4a565b2345d4852f586b7ae3ab41fd |
| Issue introduced in 5.15.59 with commit f32d5615a78a1256c4f557ccc6543866e75d03f4 and fixed in 5.15.78 with commit a3a7b2ac64de232edb67279e804932cb42f0b52a |
| Issue introduced in 5.19 with commit d0be8347c623e0ac4202a1d4e0373882821f56b0 and fixed in 6.0.8 with commit 8f7e4cf0694149a5d999d676ebd9ecf1b4cb2cc9 |
| Issue introduced in 5.19 with commit d0be8347c623e0ac4202a1d4e0373882821f56b0 and fixed in 6.1 with commit 0d0e2d032811280b927650ff3c15fe5020e82533 |
| Issue introduced in 5.18.16 with commit 59a55ec33a54a7179fa178f8aaf8b1cb8e63bd93 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2022-49909 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| net/bluetooth/l2cap_core.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/db4a0783ed78beb2ebaa32f5f785bfd79c580689 |
| https://git.kernel.org/stable/c/17c6164854f8bb80bf76f32b2c2f199c16b53703 |
| https://git.kernel.org/stable/c/7f7bfdd9a9af3b12c33d9da9a012e7f4d5c91f4b |
| https://git.kernel.org/stable/c/c1f594dddd9ffd747c39f49cc5b67a9b7677d2ab |
| https://git.kernel.org/stable/c/d9ec6e2fbd4a565b2345d4852f586b7ae3ab41fd |
| https://git.kernel.org/stable/c/a3a7b2ac64de232edb67279e804932cb42f0b52a |
| https://git.kernel.org/stable/c/8f7e4cf0694149a5d999d676ebd9ecf1b4cb2cc9 |
| https://git.kernel.org/stable/c/0d0e2d032811280b927650ff3c15fe5020e82533 |
