Linux Kernel up to 6.1.119/6.6.65/6.12.4 run_vmtests.sh huge_pte_clear reference count

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.1.119/6.6.65/6.12.4. It has been classified as problematic. This impacts the function huge_pte_clear of the file run_vmtests.sh. The manipulation leads to reference count. This vulnerability is referenced as CVE-2024-56628. No exploit is available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Linux Kernel up to 6.1.119/6.6.65/6.12.4. This issue affects the function huge_pte_clear of the file run_vmtests.sh. The manipulation with an unknown input leads to a reference count vulnerability. Using CWE to declare the problem leads to CWE-911. The product uses a reference count to manage a resource, but it does not update or incorrectly updates the reference count. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: LoongArch: Add architecture specific huge_pte_clear() When executing mm selftests run_vmtests.sh, there is such an error: BUG: Bad page state in process uffd-unit-tests pfn:00000 page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x0 flags: 0xffff0000002000(reserved|node=0|zone=0|lastcpupid=0xffff) raw: 00ffff0000002000 ffffbf0000000008 ffffbf0000000008 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set Modules linked in: snd_seq_dummy snd_seq snd_seq_device rfkill vfat fat virtio_balloon efi_pstore virtio_net pstore net_failover failover fuse nfnetlink virtio_scsi virtio_gpu virtio_dma_buf dm_multipath efivarfs CPU: 2 UID: 0 PID: 1913 Comm: uffd-unit-tests Not tainted 6.12.0 #184 Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 2/2/2022 Stack : 900000047c8ac000 0000000000000000 9000000000223a7c 900000047c8ac000 900000047c8af690 900000047c8af698 0000000000000000 900000047c8af7d8 900000047c8af7d0 900000047c8af7d0 900000047c8af5b0 0000000000000001 0000000000000001 900000047c8af698 10b3c7d53da40d26 0000010000000000 0000000000000022 0000000fffffffff fffffffffe000000 ffff800000000000 000000000000002f 0000800000000000 000000017a6d4000 90000000028f8940 0000000000000000 0000000000000000 90000000025aa5e0 9000000002905000 0000000000000000 90000000028f8940 ffff800000000000 0000000000000000 0000000000000000 0000000000000000 9000000000223a94 000000012001839c 00000000000000b0 0000000000000004 0000000000000000 0000000000071c1d ... Call Trace: [] show_stack+0x5c/0x180 [] dump_stack_lvl+0x6c/0xa0 [] bad_page+0x1a0/0x1f0 [] free_unref_folios+0xbf0/0xd20 [] folios_put_refs+0x1a4/0x2b8 [] free_pages_and_swap_cache+0x164/0x260 [] tlb_batch_pages_flush+0xa8/0x1c0 [] tlb_finish_mmu+0xa8/0x218 [] exit_mmap+0x1a0/0x360 [] __mmput+0x78/0x200 [] do_exit+0x43c/0xde8 [] do_group_exit+0x68/0x110 [] sys_exit_group+0x1c/0x20 [] do_syscall+0x94/0x130 [] handle_syscall+0xb8/0x158 Disabling lock debugging due to kernel taint BUG: non-zero pgtables_bytes on freeing mm: -16384 On LoongArch system, invalid huge pte entry should be invalid_pte_table or a single _PAGE_HUGE bit rather than a zero value. And it should be the same with invalid pmd entry, since pmd_none() is called by function free_pgd_range() and pmd_none() return 0 by huge_pte_clear(). So single _PAGE_HUGE bit is also treated as a valid pte table and free_pte_range() will be called in free_pmd_range(). free_pmd_range() pmd = pmd_offset(pud, addr); do { next = pmd_addr_end(addr, end); if (pmd_none_or_clear_bad(pmd)) continue; free_pte_range(tlb, pmd, addr); } while (pmd++, addr = next, addr != end); Here invalid_pte_table is used for both invalid huge pte entry and pmd entry.

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2024-56628 since 12/27/2024. The exploitation is known to be difficult. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 216985 (Debian dla-4076 : linux-config-6.1 - security update), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.120, 6.6.66 or 6.12.5 eliminates this vulnerability. Applying the patch dba3c45e333a3a2a01395b5f5e5f88f8baba74e4/7dfbf011a57b9e1a40f5ce8080a53c497e105c6c/9b602190cf2d8ac957be0011e418ed6c3b49b9a3/7cd1f5f77925ae905a57296932f0f9ef0dc364f8 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (216985) and CERT Bund (WID-SEC-2024-3762). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• RESF Rocky Linux
• Dell NetWorker
• Dell Avamar
• Red Hat OpenShift
• IBM QRadar SIEM
• Dell PowerProtect Data Domain
• Open Source Linux Kernel
• IBM DataPower Gateway
• Dell Secure Connect Gateway

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.1.119
• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.6.24
• 6.6.25
• 6.6.26
• 6.6.27
• 6.6.28
• 6.6.29
• 6.6.30
• 6.6.31
• 6.6.32
• 6.6.33
• 6.6.34
• 6.6.35
• 6.6.36
• 6.6.37
• 6.6.38
• 6.6.39
• 6.6.40
• 6.6.41
• 6.6.42
• 6.6.43
• 6.6.44
• 6.6.45
• 6.6.46
• 6.6.47
• 6.6.48
• 6.6.49
• 6.6.50
• 6.6.51
• 6.6.52
• 6.6.53
• 6.6.54
• 6.6.55
• 6.6.56
• 6.6.57
• 6.6.58
• 6.6.59
• 6.6.60
• 6.6.61
• 6.6.62
• 6.6.63
• 6.6.64
• 6.6.65
• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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