cve/2024/CVE-2024-39477.md
2025-09-29 21:09:30 +02:00

1.4 KiB

CVE-2024-39477

Description

In the Linux kernel, the following vulnerability has been resolved:mm/hugetlb: do not call vma_add_reservation upon ENOMEMsysbot reported a splat [1] on __unmap_hugepage_range(). This is becausevma_needs_reservation() can return -ENOMEM ifallocate_file_region_entries() fails to allocate the file_region structfor the reservation.Check for that and do not call vma_add_reservation() if that is the case,otherwise region_abort() and region_del() will see that we do not have anyfile_regions.If we detect that vma_needs_reservation() returned -ENOMEM, we clear thehugetlb_restore_reserve flag as if this reservation was still consumed, sofree_huge_folio() will not increment the resv count.[1] https://lore.kernel.org/linux-mm/0000000000004096100617c58d54@google.com/T/#ma5983bc1ab18a54910da83416b3f89f3c7ee43aa

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