发布于3月6日3月6日 Members Debian: CVE-2021-47333: linux -- security update Severity 4 CVSS (AV:L/AC:M/Au:N/C:P/I:P/A:P) Published 05/21/2024 Created 07/31/2024 Added 07/30/2024 Modified 07/30/2024 Description In the Linux kernel, the following vulnerability has been resolved: misc: alcor_pci: fix null-ptr-deref when there is no PCI bridge There is an issue with the ASPM(optional) capability checking function. A device might be attached to root complex directly, in this case, bus->self(bridge) will be NULL, thus priv->parent_pdev is NULL. Since alcor_pci_init_check_aspm(priv->parent_pdev) checks the PCI link's ASPM capability and populate parent_cap_off, which will be used later by alcor_pci_aspm_ctrl() to dynamically turn on/off device, what we can do here is to avoid checking the capability if we are on the root complex. This will make pdev_cap_off 0 and alcor_pci_aspm_ctrl() will simply return when bring called, effectively disable ASPM for the device. [1.246492] BUG: kernel NULL pointer dereference, address: 00000000000000c0 [1.248731] RIP: 0010:pci_read_config_byte+0x5/0x40 [1.253998] Call Trace: [1.254131]? alcor_pci_find_cap_offset.isra.0+0x3a/0x100 [alcor_pci] [1.254476]alcor_pci_probe+0x169/0x2d5 [alcor_pci] Solution(s) debian-upgrade-linux References https://attackerkb.com/topics/cve-2021-47333 CVE - 2021-47333
