| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2023-52975: scsi: iscsi_tcp: Fix UAF during logout when accessing the shost ipaddress |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| scsi: iscsi_tcp: Fix UAF during logout when accessing the shost ipaddress |
| |
| Bug report and analysis from Ding Hui. |
| |
| During iSCSI session logout, if another task accesses the shost ipaddress |
| attr, we can get a KASAN UAF report like this: |
| |
| [ 276.942144] BUG: KASAN: use-after-free in _raw_spin_lock_bh+0x78/0xe0 |
| [ 276.942535] Write of size 4 at addr ffff8881053b45b8 by task cat/4088 |
| [ 276.943511] CPU: 2 PID: 4088 Comm: cat Tainted: G E 6.1.0-rc8+ #3 |
| [ 276.943997] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020 |
| [ 276.944470] Call Trace: |
| [ 276.944943] <TASK> |
| [ 276.945397] dump_stack_lvl+0x34/0x48 |
| [ 276.945887] print_address_description.constprop.0+0x86/0x1e7 |
| [ 276.946421] print_report+0x36/0x4f |
| [ 276.947358] kasan_report+0xad/0x130 |
| [ 276.948234] kasan_check_range+0x35/0x1c0 |
| [ 276.948674] _raw_spin_lock_bh+0x78/0xe0 |
| [ 276.949989] iscsi_sw_tcp_host_get_param+0xad/0x2e0 [iscsi_tcp] |
| [ 276.951765] show_host_param_ISCSI_HOST_PARAM_IPADDRESS+0xe9/0x130 [scsi_transport_iscsi] |
| [ 276.952185] dev_attr_show+0x3f/0x80 |
| [ 276.953005] sysfs_kf_seq_show+0x1fb/0x3e0 |
| [ 276.953401] seq_read_iter+0x402/0x1020 |
| [ 276.954260] vfs_read+0x532/0x7b0 |
| [ 276.955113] ksys_read+0xed/0x1c0 |
| [ 276.955952] do_syscall_64+0x38/0x90 |
| [ 276.956347] entry_SYSCALL_64_after_hwframe+0x63/0xcd |
| [ 276.956769] RIP: 0033:0x7f5d3a679222 |
| [ 276.957161] Code: c0 e9 b2 fe ff ff 50 48 8d 3d 32 c0 0b 00 e8 a5 fe 01 00 0f 1f 44 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 ec 28 48 89 54 24 |
| [ 276.958009] RSP: 002b:00007ffc864d16a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 |
| [ 276.958431] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f5d3a679222 |
| [ 276.958857] RDX: 0000000000020000 RSI: 00007f5d3a4fe000 RDI: 0000000000000003 |
| [ 276.959281] RBP: 00007f5d3a4fe000 R08: 00000000ffffffff R09: 0000000000000000 |
| [ 276.959682] R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000020000 |
| [ 276.960126] R13: 0000000000000003 R14: 0000000000000000 R15: 0000557a26dada58 |
| [ 276.960536] </TASK> |
| [ 276.961357] Allocated by task 2209: |
| [ 276.961756] kasan_save_stack+0x1e/0x40 |
| [ 276.962170] kasan_set_track+0x21/0x30 |
| [ 276.962557] __kasan_kmalloc+0x7e/0x90 |
| [ 276.962923] __kmalloc+0x5b/0x140 |
| [ 276.963308] iscsi_alloc_session+0x28/0x840 [scsi_transport_iscsi] |
| [ 276.963712] iscsi_session_setup+0xda/0xba0 [libiscsi] |
| [ 276.964078] iscsi_sw_tcp_session_create+0x1fd/0x330 [iscsi_tcp] |
| [ 276.964431] iscsi_if_create_session.isra.0+0x50/0x260 [scsi_transport_iscsi] |
| [ 276.964793] iscsi_if_recv_msg+0xc5a/0x2660 [scsi_transport_iscsi] |
| [ 276.965153] iscsi_if_rx+0x198/0x4b0 [scsi_transport_iscsi] |
| [ 276.965546] netlink_unicast+0x4d5/0x7b0 |
| [ 276.965905] netlink_sendmsg+0x78d/0xc30 |
| [ 276.966236] sock_sendmsg+0xe5/0x120 |
| [ 276.966576] ____sys_sendmsg+0x5fe/0x860 |
| [ 276.966923] ___sys_sendmsg+0xe0/0x170 |
| [ 276.967300] __sys_sendmsg+0xc8/0x170 |
| [ 276.967666] do_syscall_64+0x38/0x90 |
| [ 276.968028] entry_SYSCALL_64_after_hwframe+0x63/0xcd |
| [ 276.968773] Freed by task 2209: |
| [ 276.969111] kasan_save_stack+0x1e/0x40 |
| [ 276.969449] kasan_set_track+0x21/0x30 |
| [ 276.969789] kasan_save_free_info+0x2a/0x50 |
| [ 276.970146] __kasan_slab_free+0x106/0x190 |
| [ 276.970470] __kmem_cache_free+0x133/0x270 |
| [ 276.970816] device_release+0x98/0x210 |
| [ 276.971145] kobject_cleanup+0x101/0x360 |
| [ 276.971462] iscsi_session_teardown+0x3fb/0x530 [libiscsi] |
| [ 276.971775] iscsi_sw_tcp_session_destroy+0xd8/0x130 [iscsi_tcp] |
| [ 276.972143] iscsi_if_recv_msg+0x1bf1/0x2660 [scsi_transport_iscsi] |
| [ 276.972485] iscsi_if_rx+0x198/0x4b0 [scsi_transport_iscsi] |
| [ 276.972808] netlink_unicast+0x4d5/0x7b0 |
| [ 276.973201] netlink_sendmsg+0x78d/0xc30 |
| [ 276.973544] sock_sendmsg+0xe5/0x120 |
| [ 276.973864] ____sys_sendmsg+0x5fe/0x860 |
| [ 276.974248] ___sys_sendmsg+0xe0/0x170 |
| [ 276.974583] __sys_sendmsg+0xc8/0x170 |
| [ 276.974891] do_syscall_64+0x38/0x90 |
| [ 276.975216] entry_SYSCALL_64_after_hwframe+0x63/0xcd |
| |
| We can easily reproduce by two tasks: |
| 1. while :; do iscsiadm -m node --login; iscsiadm -m node --logout; done |
| 2. while :; do cat \ |
| /sys/devices/platform/host*/iscsi_host/host*/ipaddress; done |
| |
| iscsid | cat |
| --------------------------------+--------------------------------------- |
| |- iscsi_sw_tcp_session_destroy | |
| |- iscsi_session_teardown | |
| |- device_release | |
| |- iscsi_session_release ||- dev_attr_show |
| |- kfree | |- show_host_param_ |
| | ISCSI_HOST_PARAM_IPADDRESS |
| | |- iscsi_sw_tcp_host_get_param |
| | |- r/w tcp_sw_host->session (UAF) |
| |- iscsi_host_remove | |
| |- iscsi_host_free | |
| |
| Fix the above bug by splitting the session removal into 2 parts: |
| |
| 1. removal from iSCSI class which includes sysfs and removal from host |
| tracking. |
| |
| 2. freeing of session. |
| |
| During iscsi_tcp host and session removal we can remove the session from |
| sysfs then remove the host from sysfs. At this point we know userspace is |
| not accessing the kernel via sysfs so we can free the session and host. |
| |
| The Linux kernel CVE team has assigned CVE-2023-52975 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Fixed in 5.15.93 with commit 17b738590b97fb3fc287289971d1519ff9b875a1 |
| Fixed in 6.1.11 with commit 8859687f5b242c0b057461df0a9ff51d5500783b |
| Fixed in 6.2 with commit 6f1d64b13097e85abda0f91b5638000afc5f9a06 |
| |
| 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-2023-52975 |
| 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: |
| drivers/scsi/iscsi_tcp.c |
| drivers/scsi/libiscsi.c |
| include/scsi/libiscsi.h |
| |
| |
| 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/17b738590b97fb3fc287289971d1519ff9b875a1 |
| https://git.kernel.org/stable/c/8859687f5b242c0b057461df0a9ff51d5500783b |
| https://git.kernel.org/stable/c/6f1d64b13097e85abda0f91b5638000afc5f9a06 |
