摘要:

In the Linux kernel, the following vulnerability has been resolved:PCI/ASPM: Fix deadlock when enabling ASPMA last minute revert in 6.7-final introduced a potential deadlock whenenabling ASPM during probe of Qualcomm PCIe controllers as reported bylockdep: ============================================ WARNING: possible recursive locking detected 6.7.0 #40 Not tainted -------------------------------------------- kworker/u16:5/90 is trying to acquire lock: ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pcie_aspm_pm_state_change+0x58/0xdc but task is already holding lock: ffffacfa78ced000 (pci_bus_sem){++++}-{3:3}, at: pci_walk_bus+0x34/0xbc other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(pci_bus_sem); lock(pci_bus_sem); *** DEADLOCK *** Call trace: print_deadlock_bug+0x25c/0x348 __lock_acquire+0x10a4/0x2064 lock_acquire+0x1e8/0x318 down_read+0x60/0x184 pcie_aspm_pm_state_change+0x58/0xdc pci_set_full_power_state+0xa8/0x114 pci_set_power_state+0xc4/0x120 qcom_pcie_enable_aspm+0x1c/0x3c [pcie_qcom] pci_walk_bus+0x64/0xbc qcom_pcie_host_post_init_2_7_0+0x28/0x34 [pcie_qcom]The deadlock can easily be reproduced on machines like the Lenovo ThinkPadX13s by adding a delay to increase the race window during asynchronousprobe where another thread can take a write lock.Add a new pci_set_power_state_locked() and associated helper functions thatcan be called with the PCI bus semaphore held to avoid taking the read locktwice.

安全等级: Low

公告ID: KylinSec-SA-2024-2243

发布日期: 2024年5月27日

关联CVE: CVE-2024-26605