We use these services and cookies to improve your user experience. You may opt out if you wish, however, this may limit some features on this site.

Please see our statement on Data Privacy.

Zendesk (Helpdesk and Chat)
Bugpilot (Bug tracking)

Ok

THREATINT CVE Home CVE Diag Help
PUBLISHED

CVE-2024-26762

cxl/pci: Skip to handle RAS errors if CXL.mem device is detached

Reserved:2024-02-19
Published:2024-04-03
Updated:2024-04-03

Description

In the Linux kernel, the following vulnerability has been resolved: cxl/pci: Skip to handle RAS errors if CXL.mem device is detached The PCI AER model is an awkward fit for CXL error handling. While the expectation is that a PCI device can escalate to link reset to recover from an AER event, the same reset on CXL amounts to a surprise memory hotplug of massive amounts of memory. At present, the CXL error handler attempts some optimistic error handling to unbind the device from the cxl_mem driver after reaping some RAS register values. This results in a "hopeful" attempt to unplug the memory, but there is no guarantee that will succeed. A subsequent AER notification after the memdev unbind event can no longer assume the registers are mapped. Check for memdev bind before reaping status register values to avoid crashes of the form: BUG: unable to handle page fault for address: ffa00000195e9100 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page [...] RIP: 0010:__cxl_handle_ras+0x30/0x110 [cxl_core] [...] Call Trace: <TASK> ? __die+0x24/0x70 ? page_fault_oops+0x82/0x160 ? kernelmode_fixup_or_oops+0x84/0x110 ? exc_page_fault+0x113/0x170 ? asm_exc_page_fault+0x26/0x30 ? __pfx_dpc_reset_link+0x10/0x10 ? __cxl_handle_ras+0x30/0x110 [cxl_core] ? find_cxl_port+0x59/0x80 [cxl_core] cxl_handle_rp_ras+0xbc/0xd0 [cxl_core] cxl_error_detected+0x6c/0xf0 [cxl_core] report_error_detected+0xc7/0x1c0 pci_walk_bus+0x73/0x90 pcie_do_recovery+0x23f/0x330 Longer term, the unbind and PCI_ERS_RESULT_DISCONNECT behavior might need to be replaced with a new PCI_ERS_RESULT_PANIC.

Product status

Default status
unaffected

6ac07883dbb5 before 21e5e84f3f63
affected

6ac07883dbb5 before eef5c7b28dbe
affected

Default status
affected

6.7
affected

Any version before 6.7
unaffected

6.7.7
unaffected

6.8
unaffected

References

https://git.kernel.org/stable/c/21e5e84f3f63fdf44e49642a6e45cd895e921a84

https://git.kernel.org/stable/c/eef5c7b28dbecd6b141987a96db6c54e49828102

cve.org CVE-2024-26762

nvd.nist.gov CVE-2024-26762

Download JSON

Share this page
https://cve.threatint.com/CVE/CVE-2024-26762