ghsa-cw8x-f629-7c3v
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
net/smc: Forward wakeup to smc socket waitqueue after fallback
When we replace TCP with SMC and a fallback occurs, there may be some socket waitqueue entries remaining in smc socket->wq, such as eppoll_entries inserted by userspace applications.
After the fallback, data flows over TCP/IP and only clcsocket->wq will be woken up. Applications can't be notified by the entries which were inserted in smc socket->wq before fallback. So we need a mechanism to wake up smc socket->wq at the same time if some entries remaining in it.
The current workaround is to transfer the entries from smc socket->wq to clcsock->wq during the fallback. But this may cause a crash like this:
general protection fault, probably for non-canonical address 0xdead000000000100: 0000 [#1] PREEMPT SMP PTI
CPU: 3 PID: 0 Comm: swapper/3 Kdump: loaded Tainted: G E 5.16.0+ #107
RIP: 0010:__wake_up_common+0x65/0x170
Call Trace:
The crash is caused by privately transferring waitqueue entries from smc socket->wq to clcsock->wq. The owners of these entries, such as epoll, have no idea that the entries have been transferred to a different socket wait queue and still use original waitqueue spinlock (smc socket->wq.wait.lock) to make the entries operation exclusive, but it doesn't work. The operations to the entries, such as removing from the waitqueue (now is clcsock->wq after fallback), may cause a crash when clcsock waitqueue is being iterated over at the moment.
This patch tries to fix this by no longer transferring wait queue entries privately, but introducing own implementations of clcsock's callback functions in fallback situation. The callback functions will forward the wakeup to smc socket->wq if clcsock->wq is actually woken up and smc socket->wq has remaining entries.
{
"affected": [],
"aliases": [
"CVE-2022-48721"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-06-20T11:15:55Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: Forward wakeup to smc socket waitqueue after fallback\n\nWhen we replace TCP with SMC and a fallback occurs, there may be\nsome socket waitqueue entries remaining in smc socket-\u003ewq, such\nas eppoll_entries inserted by userspace applications.\n\nAfter the fallback, data flows over TCP/IP and only clcsocket-\u003ewq\nwill be woken up. Applications can\u0027t be notified by the entries\nwhich were inserted in smc socket-\u003ewq before fallback. So we need\na mechanism to wake up smc socket-\u003ewq at the same time if some\nentries remaining in it.\n\nThe current workaround is to transfer the entries from smc socket-\u003ewq\nto clcsock-\u003ewq during the fallback. But this may cause a crash\nlike this:\n\n general protection fault, probably for non-canonical address 0xdead000000000100: 0000 [#1] PREEMPT SMP PTI\n CPU: 3 PID: 0 Comm: swapper/3 Kdump: loaded Tainted: G E 5.16.0+ #107\n RIP: 0010:__wake_up_common+0x65/0x170\n Call Trace:\n \u003cIRQ\u003e\n __wake_up_common_lock+0x7a/0xc0\n sock_def_readable+0x3c/0x70\n tcp_data_queue+0x4a7/0xc40\n tcp_rcv_established+0x32f/0x660\n ? sk_filter_trim_cap+0xcb/0x2e0\n tcp_v4_do_rcv+0x10b/0x260\n tcp_v4_rcv+0xd2a/0xde0\n ip_protocol_deliver_rcu+0x3b/0x1d0\n ip_local_deliver_finish+0x54/0x60\n ip_local_deliver+0x6a/0x110\n ? tcp_v4_early_demux+0xa2/0x140\n ? tcp_v4_early_demux+0x10d/0x140\n ip_sublist_rcv_finish+0x49/0x60\n ip_sublist_rcv+0x19d/0x230\n ip_list_rcv+0x13e/0x170\n __netif_receive_skb_list_core+0x1c2/0x240\n netif_receive_skb_list_internal+0x1e6/0x320\n napi_complete_done+0x11d/0x190\n mlx5e_napi_poll+0x163/0x6b0 [mlx5_core]\n __napi_poll+0x3c/0x1b0\n net_rx_action+0x27c/0x300\n __do_softirq+0x114/0x2d2\n irq_exit_rcu+0xb4/0xe0\n common_interrupt+0xba/0xe0\n \u003c/IRQ\u003e\n \u003cTASK\u003e\n\nThe crash is caused by privately transferring waitqueue entries from\nsmc socket-\u003ewq to clcsock-\u003ewq. The owners of these entries, such as\nepoll, have no idea that the entries have been transferred to a\ndifferent socket wait queue and still use original waitqueue spinlock\n(smc socket-\u003ewq.wait.lock) to make the entries operation exclusive,\nbut it doesn\u0027t work. The operations to the entries, such as removing\nfrom the waitqueue (now is clcsock-\u003ewq after fallback), may cause a\ncrash when clcsock waitqueue is being iterated over at the moment.\n\nThis patch tries to fix this by no longer transferring wait queue\nentries privately, but introducing own implementations of clcsock\u0027s\ncallback functions in fallback situation. The callback functions will\nforward the wakeup to smc socket-\u003ewq if clcsock-\u003ewq is actually woken\nup and smc socket-\u003ewq has remaining entries.",
"id": "GHSA-cw8x-f629-7c3v",
"modified": "2024-06-20T12:31:20Z",
"published": "2024-06-20T12:31:20Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-48721"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/0ef6049f664941bc0f75828b3a61877635048b27"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/341adeec9adad0874f29a0a1af35638207352a39"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/504078fbe9dd570d685361b57784a6050bc40aaa"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
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