ghsa-p7rj-mgww-3q4f
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
SUNRPC: Fix UAF in svc_tcp_listen_data_ready()
After the listener svc_sock is freed, and before invoking svc_tcp_accept() for the established child sock, there is a window that the newsock retaining a freed listener svc_sock in sk_user_data which cloning from parent. In the race window, if data is received on the newsock, we will observe use-after-free report in svc_tcp_listen_data_ready().
Reproduce by two tasks:
- while :; do rpc.nfsd 0 ; rpc.nfsd; done
- while :; do echo "" | ncat -4 127.0.0.1 2049 ; done
KASAN report:
==================================================================
BUG: KASAN: slab-use-after-free in svc_tcp_listen_data_ready+0x1cf/0x1f0 [sunrpc]
Read of size 8 at addr ffff888139d96228 by task nc/102553
CPU: 7 PID: 102553 Comm: nc Not tainted 6.3.0+ #18
Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020
Call Trace:
Allocated by task 102371: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 __kasan_kmalloc+0x7b/0x90 svc_setup_socket+0x52/0x4f0 [sunrpc] svc_addsock+0x20d/0x400 [sunrpc] __write_ports_addfd+0x209/0x390 [nfsd] write_ports+0x239/0x2c0 [nfsd] nfsctl_transaction_write+0xac/0x110 [nfsd] vfs_write+0x1c3/0xae0 ksys_write+0xed/0x1c0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc
Freed by task 102551: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_save_free_info+0x2a/0x50 __kasan_slab_free+0x106/0x190 __kmem_cache_free+0x133/0x270 svc_xprt_free+0x1e2/0x350 [sunrpc] svc_xprt_destroy_all+0x25a/0x440 [sunrpc] nfsd_put+0x125/0x240 [nfsd] nfsd_svc+0x2cb/0x3c0 [nfsd] write_threads+0x1ac/0x2a0 [nfsd] nfsctl_transaction_write+0xac/0x110 [nfsd] vfs_write+0x1c3/0xae0 ksys_write+0xed/0x1c0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc
Fix the UAF by simply doing nothing in svc_tcp_listen_data_ready() if state != TCP_LISTEN, that will avoid dereferencing svsk for all child socket.
{ "affected": [], "aliases": [ "CVE-2023-52885" ], "database_specific": { "cwe_ids": [ "CWE-416" ], "github_reviewed": false, "github_reviewed_at": null, "nvd_published_at": "2024-07-14T08:15:01Z", "severity": "HIGH" }, "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nSUNRPC: Fix UAF in svc_tcp_listen_data_ready()\n\nAfter the listener svc_sock is freed, and before invoking svc_tcp_accept()\nfor the established child sock, there is a window that the newsock\nretaining a freed listener svc_sock in sk_user_data which cloning from\nparent. In the race window, if data is received on the newsock, we will\nobserve use-after-free report in svc_tcp_listen_data_ready().\n\nReproduce by two tasks:\n\n1. while :; do rpc.nfsd 0 ; rpc.nfsd; done\n2. while :; do echo \"\" | ncat -4 127.0.0.1 2049 ; done\n\nKASAN report:\n\n ==================================================================\n BUG: KASAN: slab-use-after-free in svc_tcp_listen_data_ready+0x1cf/0x1f0 [sunrpc]\n Read of size 8 at addr ffff888139d96228 by task nc/102553\n CPU: 7 PID: 102553 Comm: nc Not tainted 6.3.0+ #18\n Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020\n Call Trace:\n \u003cIRQ\u003e\n dump_stack_lvl+0x33/0x50\n print_address_description.constprop.0+0x27/0x310\n print_report+0x3e/0x70\n kasan_report+0xae/0xe0\n svc_tcp_listen_data_ready+0x1cf/0x1f0 [sunrpc]\n tcp_data_queue+0x9f4/0x20e0\n tcp_rcv_established+0x666/0x1f60\n tcp_v4_do_rcv+0x51c/0x850\n tcp_v4_rcv+0x23fc/0x2e80\n ip_protocol_deliver_rcu+0x62/0x300\n ip_local_deliver_finish+0x267/0x350\n ip_local_deliver+0x18b/0x2d0\n ip_rcv+0x2fb/0x370\n __netif_receive_skb_one_core+0x166/0x1b0\n process_backlog+0x24c/0x5e0\n __napi_poll+0xa2/0x500\n net_rx_action+0x854/0xc90\n __do_softirq+0x1bb/0x5de\n do_softirq+0xcb/0x100\n \u003c/IRQ\u003e\n \u003cTASK\u003e\n ...\n \u003c/TASK\u003e\n\n Allocated by task 102371:\n kasan_save_stack+0x1e/0x40\n kasan_set_track+0x21/0x30\n __kasan_kmalloc+0x7b/0x90\n svc_setup_socket+0x52/0x4f0 [sunrpc]\n svc_addsock+0x20d/0x400 [sunrpc]\n __write_ports_addfd+0x209/0x390 [nfsd]\n write_ports+0x239/0x2c0 [nfsd]\n nfsctl_transaction_write+0xac/0x110 [nfsd]\n vfs_write+0x1c3/0xae0\n ksys_write+0xed/0x1c0\n do_syscall_64+0x38/0x90\n entry_SYSCALL_64_after_hwframe+0x72/0xdc\n\n Freed by task 102551:\n kasan_save_stack+0x1e/0x40\n kasan_set_track+0x21/0x30\n kasan_save_free_info+0x2a/0x50\n __kasan_slab_free+0x106/0x190\n __kmem_cache_free+0x133/0x270\n svc_xprt_free+0x1e2/0x350 [sunrpc]\n svc_xprt_destroy_all+0x25a/0x440 [sunrpc]\n nfsd_put+0x125/0x240 [nfsd]\n nfsd_svc+0x2cb/0x3c0 [nfsd]\n write_threads+0x1ac/0x2a0 [nfsd]\n nfsctl_transaction_write+0xac/0x110 [nfsd]\n vfs_write+0x1c3/0xae0\n ksys_write+0xed/0x1c0\n do_syscall_64+0x38/0x90\n entry_SYSCALL_64_after_hwframe+0x72/0xdc\n\nFix the UAF by simply doing nothing in svc_tcp_listen_data_ready()\nif state != TCP_LISTEN, that will avoid dereferencing svsk for all\nchild socket.", "id": "GHSA-p7rj-mgww-3q4f", "modified": "2024-08-21T18:31:26Z", "published": "2024-07-14T09:30:35Z", "references": [ { "type": "ADVISORY", "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-52885" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/42725e5c1b181b757ba11d804443922982334d9b" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/7e1f989055622fd086c5dfb291fc72adf5660b6f" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/c7b8c2d06e437639694abe76978e915cfb73f428" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/cd5ec3ee52ce4b7e283cc11facfa420c297c8065" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/dfc896c4a75cb8cd7cb2dfd9b469cf1e3f004254" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/ef047411887ff0845afd642d6a687819308e1a4e" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/fbf4ace39b2e4f3833236afbb2336edbafd75eee" }, { "type": "WEB", "url": "https://git.kernel.org/stable/c/fc80fc2d4e39137869da3150ee169b40bf879287" } ], "schema_version": "1.4.0", "severity": [ { "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "type": "CVSS_V3" } ] }
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.