{"id":"AZL-66815","summary":"CVE-2025-38681 affecting package kernel for versions less than 6.6.104.2-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/ptdump: take the memory hotplug lock inside ptdump_walk_pgd()\n\nMemory hot remove unmaps and tears down various kernel page table regions\nas required.  The ptdump code can race with concurrent modifications of\nthe kernel page tables.  When leaf entries are modified concurrently, the\ndump code may log stale or inconsistent information for a VA range, but\nthis is otherwise not harmful.\n\nBut when intermediate levels of kernel page table are freed, the dump code\nwill continue to use memory that has been freed and potentially\nreallocated for another purpose.  In such cases, the ptdump code may\ndereference bogus addresses, leading to a number of potential problems.\n\nTo avoid the above mentioned race condition, platforms such as arm64,\nriscv and s390 take memory hotplug lock, while dumping kernel page table\nvia the sysfs interface /sys/kernel/debug/kernel_page_tables.\n\nSimilar race condition exists while checking for pages that might have\nbeen marked W+X via /sys/kernel/debug/kernel_page_tables/check_wx_pages\nwhich in turn calls ptdump_check_wx().  Instead of solving this race\ncondition again, let's just move the memory hotplug lock inside generic\nptdump_check_wx() which will benefit both the scenarios.\n\nDrop get_online_mems() and put_online_mems() combination from all existing\nplatform ptdump code paths.","modified":"2026-04-01T05:21:03.747051Z","published":"2025-09-04T16:15:35Z","upstream":["CVE-2025-38681"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-38681"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.104.2-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-66815.json"}}],"schema_version":"1.7.5"}