Bugzilla – Bug 1227439
VUL-0: CVE-2024-39477: kernel: mm/hugetlb: do not call vma_add_reservation upon ENOMEM
Last modified: 2024-07-08 09:16:05 UTC
In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: do not call vma_add_reservation upon ENOMEM sysbot reported a splat [1] on __unmap_hugepage_range(). This is because vma_needs_reservation() can return -ENOMEM if allocate_file_region_entries() fails to allocate the file_region struct for 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 any file_regions. If we detect that vma_needs_reservation() returned -ENOMEM, we clear the hugetlb_restore_reserve flag as if this reservation was still consumed, so free_huge_folio() will not increment the resv count. [1] https://lore.kernel.org/linux-mm/0000000000004096100617c58d54@google.com/T/#ma5983bc1ab18a54910da83416b3f89f3c7ee43aa References: http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2024-39477 https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2024/CVE-2024-39477.mbox https://git.kernel.org/stable/c/aa998f9dcb34c28448f86e8f5490f20d5eb0eac7 https://git.kernel.org/stable/c/8daf9c702ee7f825f0de8600abff764acfedea13 https://www.cve.org/CVERecord?id=CVE-2024-39477
All done, closing.