CVE-2024-26725

CVE Details

Release Date:

2024-04-03

Description

In the Linux kernel, the following vulnerability has been resolved:\ndpll: fix possible deadlock during netlink dump operation\nRecently, I've been hitting following deadlock warning during dpll pin\ndump:\n[52804.637962] ======================================================\n[52804.638536] WARNING: possible circular locking dependency detected\n[52804.639111] 6.8.0-rc2jiri+ #1 Not tainted\n[52804.639529] ------------------------------------------------------\n[52804.640104] python3/2984 is trying to acquire lock:\n[52804.640581] ffff88810e642678 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}, at: netlink_dump+0xb3/0x780\n[52804.641417]\nbut task is already holding lock:\n[52804.642010] ffffffff83bde4c8 (dpll_lock){+.+.}-{3:3}, at: dpll_lock_dumpit+0x13/0x20\n[52804.642747]\nwhich lock already depends on the new lock.\n[52804.643551]\nthe existing dependency chain (in reverse order) is:\n[52804.644259]\n-> #1 (dpll_lock){+.+.}-{3:3}:\n[52804.644836] lock_acquire+0x174/0x3e0\n[52804.645271] __mutex_lock+0x119/0x1150\n[52804.645723] dpll_lock_dumpit+0x13/0x20\n[52804.646169] genl_start+0x266/0x320\n[52804.646578] __netlink_dump_start+0x321/0x450\n[52804.647056] genl_family_rcv_msg_dumpit+0x155/0x1e0\n[52804.647575] genl_rcv_msg+0x1ed/0x3b0\n[52804.648001] netlink_rcv_skb+0xdc/0x210\n[52804.648440] genl_rcv+0x24/0x40\n[52804.648831] netlink_unicast+0x2f1/0x490\n[52804.649290] netlink_sendmsg+0x36d/0x660\n[52804.649742] __sock_sendmsg+0x73/0xc0\n[52804.650165] __sys_sendto+0x184/0x210\n[52804.650597] __x64_sys_sendto+0x72/0x80\n[52804.651045] do_syscall_64+0x6f/0x140\n[52804.651474] entry_SYSCALL_64_after_hwframe+0x46/0x4e\n[52804.652001]\n-> #0 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}:\n[52804.652650] check_prev_add+0x1ae/0x1280\n[52804.653107] __lock_acquire+0x1ed3/0x29a0\n[52804.653559] lock_acquire+0x174/0x3e0\n[52804.653984] __mutex_lock+0x119/0x1150\n[52804.654423] netlink_dump+0xb3/0x780\n[52804.654845] __netlink_dump_start+0x389/0x450\n[52804.655321] genl_family_rcv_msg_dumpit+0x155/0x1e0\n[52804.655842] genl_rcv_msg+0x1ed/0x3b0\n[52804.656272] netlink_rcv_skb+0xdc/0x210\n[52804.656721] genl_rcv+0x24/0x40\n[52804.657119] netlink_unicast+0x2f1/0x490\n[52804.657570] netlink_sendmsg+0x36d/0x660\n[52804.658022] __sock_sendmsg+0x73/0xc0\n[52804.658450] __sys_sendto+0x184/0x210\n[52804.658877] __x64_sys_sendto+0x72/0x80\n[52804.659322] do_syscall_64+0x6f/0x140\n[52804.659752] entry_SYSCALL_64_after_hwframe+0x46/0x4e\n[52804.660281]\nother info that might help us debug this:\n[52804.661077] Possible unsafe locking scenario:\n[52804.661671] CPU0 CPU1\n[52804.662129] ---- ----\n[52804.662577] lock(dpll_lock);\n[52804.662924] lock(nlk_cb_mutex-GENERIC);\n[52804.663538] lock(dpll_lock);\n[52804.664073] lock(nlk_cb_mutex-GENERIC);\n[52804.664490]\nThe issue as follows: __netlink_dump_start() calls control->start(cb)\nwith nlk->cb_mutex held. In control->start(cb) the dpll_lock is taken.\nThen nlk->cb_mutex is released and taken again in netlink_dump(), while\ndpll_lock still being held. That leads to ABBA deadlock when another\nCPU races with the same operation.\nFix this by moving dpll_lock taking into dumpit() callback which ensures\ncorrect lock taking order.

See more information about CVE-2024-26725 from MITRE CVE dictionary and NIST NVD

CVSS Scoring

NOTE: The following CVSS v3.1 metrics and score provided are preliminary and subject to review.

Base Score:	4.4	CVSS Vector:	CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Attack Vector:	Local network	Attack Complexity:	Low
Privileges Required:	High	User Interaction:	None
Scope:	Unchanged	Confidentiality Impact:	None
Integrity Impact:	None	Availability Impact:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 9 (kernel)	ELSA-2024-9315	2024-11-14