CVE-2021-47090: In the Linux kernel, the following vulnerability has been resolved: mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page() Hulk Robot ...

Description

In the Linux kernel, the following vulnerability has been resolved: mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page() Hulk Robot reported a panic in put_page_testzero() when testing madvise() with MADV_SOFT_OFFLINE. The BUG() is triggered when retrying get_any_page(). This is because we keep MF_COUNT_INCREASED flag in second try but the refcnt is not increased. page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0) ------------[ cut here ]------------ kernel BUG at include/linux/mm.h:737! invalid opcode: 0000 [#1] PREEMPT SMP CPU: 5 PID: 2135 Comm: sshd Tainted: G B 5.16.0-rc6-dirty #373 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: release_pages+0x53f/0x840 Call Trace: free_pages_and_swap_cache+0x64/0x80 tlb_flush_mmu+0x6f/0x220 unmap_page_range+0xe6c/0x12c0 unmap_single_vma+0x90/0x170 unmap_vmas+0xc4/0x180 exit_mmap+0xde/0x3a0 mmput+0xa3/0x250 do_exit+0x564/0x1470 do_group_exit+0x3b/0x100 __do_sys_exit_group+0x13/0x20 __x64_sys_exit_group+0x16/0x20 do_syscall_64+0x34/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Modules linked in: ---[ end trace e99579b570fe0649 ]--- RIP: 0010:release_pages+0x53f/0x840

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.35%

27.1th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions	Update
Linux	Linux Kernel	>= 5.10, < 5.10.89	—
Linux	Linux Kernel	>= 5.11, < 5.15.12	—
Linux	Linux Kernel	5.16	Rc1

References

https://git.kernel.org/stable/c/1f207076740101fed87074a6bc924dbe806f08a5Exploit, Mailing List, Patch
https://git.kernel.org/stable/c/2a57d83c78f889bf3f54eede908d0643c40d5418Exploit, Mailing List, Patch
https://git.kernel.org/stable/c/c691e7575eff76e563b0199c23ec46bd454f43e3Exploit, Mailing List, Patch
https://git.kernel.org/stable/c/1f207076740101fed87074a6bc924dbe806f08a5Exploit, Mailing List, Patch
https://git.kernel.org/stable/c/2a57d83c78f889bf3f54eede908d0643c40d5418Exploit, Mailing List, Patch
https://git.kernel.org/stable/c/c691e7575eff76e563b0199c23ec46bd454f43e3Exploit, Mailing List, Patch

Timeline

Published: Mar 4, 2024
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2021-47090?

In the Linux kernel, the following vulnerability has been resolved: mm/hwpoison: clear MF_COUNT_INCREASED before retrying get_any_page() Hulk Robot reported a panic in put_page_testzero() when testing madvise() with MADV_SOFT_OFFLINE. The BUG() is triggered when retrying get_any_page(). This is because we keep MF_COUNT_INCREASED flag in second try but the refcnt is not increased. page dumped because: VM_BUG_ON_PAGE(page_ref_count(page) == 0) ------------[ cut here ]------------ kernel BUG at include/linux/mm.h:737! invalid opcode: 0000 [#1] PREEMPT SMP CPU: 5 PID: 2135 Comm: sshd Tainted: G B 5.16.0-rc6-dirty #373 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: release_pages+0x53f/0x840 Call Trace: free_pages_and_swap_cache+0x64/0x80 tlb_flush_mmu+0x6f/0x220 unmap_page_range+0xe6c/0x12c0 unmap_single_vma+0x90/0x170 unmap_vmas+0xc4/0x180 exit_mmap+0xde/0x3a0 mmput+0xa3/0x250 do_exit+0x564/0x1470 do_group_exit+0x3b/0x100 __do_sys_exit_group+0x13/0x20 __x64_sys_exit_group+0x16/0x20 do_syscall_64+0x34/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae Modules linked in: ---[ end trace e99579b570fe0649 ]--- RIP: 0010:release_pages+0x53f/0x840

How severe is CVE-2021-47090?

CVE-2021-47090 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.35% probability of exploitation in the next 30 days.

How do I fix CVE-2021-47090?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.