{"id":"AZL-74739","summary":"CVE-2025-39883 affecting package kernel for versions less than 5.15.200.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/memory-failure: fix VM_BUG_ON_PAGE(PagePoisoned(page)) when unpoison memory\n\nWhen I did memory failure tests, below panic occurs:\n\npage dumped because: VM_BUG_ON_PAGE(PagePoisoned(page))\nkernel BUG at include/linux/page-flags.h:616!\nOops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI\nCPU: 3 PID: 720 Comm: bash Not tainted 6.10.0-rc1-00195-g148743902568 #40\nRIP: 0010:unpoison_memory+0x2f3/0x590\nRSP: 0018:ffffa57fc8787d60 EFLAGS: 00000246\nRAX: 0000000000000037 RBX: 0000000000000009 RCX: ffff9be25fcdc9c8\nRDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff9be25fcdc9c0\nRBP: 0000000000300000 R08: ffffffffb4956f88 R09: 0000000000009ffb\nR10: 0000000000000284 R11: ffffffffb4926fa0 R12: ffffe6b00c000000\nR13: ffff9bdb453dfd00 R14: 0000000000000000 R15: fffffffffffffffe\nFS:  00007f08f04e4740(0000) GS:ffff9be25fcc0000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000564787a30410 CR3: 000000010d4e2000 CR4: 00000000000006f0\nCall Trace:\n \u003cTASK\u003e\n unpoison_memory+0x2f3/0x590\n simple_attr_write_xsigned.constprop.0.isra.0+0xb3/0x110\n debugfs_attr_write+0x42/0x60\n full_proxy_write+0x5b/0x80\n vfs_write+0xd5/0x540\n ksys_write+0x64/0xe0\n do_syscall_64+0xb9/0x1d0\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\nRIP: 0033:0x7f08f0314887\nRSP: 002b:00007ffece710078 EFLAGS: 00000246 ORIG_RAX: 0000000000000001\nRAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007f08f0314887\nRDX: 0000000000000009 RSI: 0000564787a30410 RDI: 0000000000000001\nRBP: 0000564787a30410 R08: 000000000000fefe R09: 000000007fffffff\nR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009\nR13: 00007f08f041b780 R14: 00007f08f0417600 R15: 00007f08f0416a00\n \u003c/TASK\u003e\nModules linked in: hwpoison_inject\n---[ end trace 0000000000000000 ]---\nRIP: 0010:unpoison_memory+0x2f3/0x590\nRSP: 0018:ffffa57fc8787d60 EFLAGS: 00000246\nRAX: 0000000000000037 RBX: 0000000000000009 RCX: ffff9be25fcdc9c8\nRDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff9be25fcdc9c0\nRBP: 0000000000300000 R08: ffffffffb4956f88 R09: 0000000000009ffb\nR10: 0000000000000284 R11: ffffffffb4926fa0 R12: ffffe6b00c000000\nR13: ffff9bdb453dfd00 R14: 0000000000000000 R15: fffffffffffffffe\nFS:  00007f08f04e4740(0000) GS:ffff9be25fcc0000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 0000564787a30410 CR3: 000000010d4e2000 CR4: 00000000000006f0\nKernel panic - not syncing: Fatal exception\nKernel Offset: 0x31c00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)\n---[ end Kernel panic - not syncing: Fatal exception ]---\n\nThe root cause is that unpoison_memory() tries to check the PG_HWPoison\nflags of an uninitialized page.  So VM_BUG_ON_PAGE(PagePoisoned(page)) is\ntriggered.  This can be reproduced by below steps:\n\n1.Offline memory block:\n\n echo offline \u003e /sys/devices/system/memory/memory12/state\n\n2.Get offlined memory pfn:\n\n page-types -b n -rlN\n\n3.Write pfn to unpoison-pfn\n\n echo \u003cpfn\u003e \u003e /sys/kernel/debug/hwpoison/unpoison-pfn\n\nThis scenario can be identified by pfn_to_online_page() returning NULL. \nAnd ZONE_DEVICE pages are never expected, so we can simply fail if\npfn_to_online_page() == NULL to fix the bug.","modified":"2026-04-01T05:22:45.842387Z","published":"2025-09-23T06:15:48Z","upstream":["CVE-2025-39883"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-39883"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:2","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.15.200.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-74739.json"}}],"schema_version":"1.7.5"}