CVE-2024-42233

In the Linux kernel, the following vulnerability has been resolved: filemap: replace pte_offset_map() with pte_offset_map_nolock() The vmf->ptl in filemap_fault_recheck_pte_none() is still set from handle_pte_fault(). But at the same time, we did a pte_unmap(vmf->pte). After a pte_unmap(vmf->pte) unmap and rcu_read_unlock(), the page table may be racily changed and vmf->ptl maybe fails to protect the actual page table. Fix this by replacing pte_offset_map() with pte_offset_map_nolock(). As David said, the PTL pointer might be stale so if we continue to use it infilemap_fault_recheck_pte_none(), it might trigger UAF. Also, if the PTL fails, the issue fixed by commit 58f327f2ce80 ("filemap: avoid unnecessary major faults in filemap_fault()") might reappear.

CVSS v3 3.3 LOW

3.3^/10

CVSS v3 : LOW

Vector :

Exploitability : 1.8 / Impact : 1.4

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/24be02a42181f0707be0498045c4c4b13273b16d	Patch
https://git.kernel.org/stable/c/6a6c2aec1a89506595801b4cf7e8eef035f33748	Patch

Configurations

Configuration 1 (hide)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2024-08-07 16:15

Updated : 2024-08-08 14:56

NVD link : CVE-2024-42233

Mitre link : CVE-2024-42233

CVE.ORG link : CVE-2024-42233

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

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