Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1000 CNY

100.0%
Buy Us a Coffee

CVE-2022-49760— mm/hugetlb: fix PTE marker handling in hugetlb_change_protection()

EPSS 0.10% · P26
Get alerts for future matching vulnerabilitiesLog in to subscribe

I. Basic Information for CVE-2022-49760

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
mm/hugetlb: fix PTE marker handling in hugetlb_change_protection()
Source: NVD (National Vulnerability Database)
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: fix PTE marker handling in hugetlb_change_protection() Patch series "mm/hugetlb: uffd-wp fixes for hugetlb_change_protection()". Playing with virtio-mem and background snapshots (using uffd-wp) on hugetlb in QEMU, I managed to trigger a VM_BUG_ON(). Looking into the details, hugetlb_change_protection() seems to not handle uffd-wp correctly in all cases. Patch #1 fixes my test case. I don't have reproducers for patch #2, as it requires running into migration entries. I did not yet check in detail yet if !hugetlb code requires similar care. This patch (of 2): There are two problematic cases when stumbling over a PTE marker in hugetlb_change_protection(): (1) We protect an uffd-wp PTE marker a second time using uffd-wp: we will end up in the "!huge_pte_none(pte)" case and mess up the PTE marker. (2) We unprotect a uffd-wp PTE marker: we will similarly end up in the "!huge_pte_none(pte)" case even though we cleared the PTE, because the "pte" variable is stale. We'll mess up the PTE marker. For example, if we later stumble over such a "wrongly modified" PTE marker, we'll treat it like a present PTE that maps some garbage page. This can, for example, be triggered by mapping a memfd backed by huge pages, registering uffd-wp, uffd-wp'ing an unmapped page and (a) uffd-wp'ing it a second time; or (b) uffd-unprotecting it; or (c) unregistering uffd-wp. Then, ff we trigger fallocate(FALLOC_FL_PUNCH_HOLE) on that file range, we will run into a VM_BUG_ON: [ 195.039560] page:00000000ba1f2987 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x0 [ 195.039565] flags: 0x7ffffc0001000(reserved|node=0|zone=0|lastcpupid=0x1fffff) [ 195.039568] raw: 0007ffffc0001000 ffffe742c0000008 ffffe742c0000008 0000000000000000 [ 195.039569] raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 [ 195.039569] page dumped because: VM_BUG_ON_PAGE(compound && !PageHead(page)) [ 195.039573] ------------[ cut here ]------------ [ 195.039574] kernel BUG at mm/rmap.c:1346! [ 195.039579] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [ 195.039581] CPU: 7 PID: 4777 Comm: qemu-system-x86 Not tainted 6.0.12-200.fc36.x86_64 #1 [ 195.039583] Hardware name: LENOVO 20WNS1F81N/20WNS1F81N, BIOS N35ET50W (1.50 ) 09/15/2022 [ 195.039584] RIP: 0010:page_remove_rmap+0x45b/0x550 [ 195.039588] Code: [...] [ 195.039589] RSP: 0018:ffffbc03c3633ba8 EFLAGS: 00010292 [ 195.039591] RAX: 0000000000000040 RBX: ffffe742c0000000 RCX: 0000000000000000 [ 195.039592] RDX: 0000000000000002 RSI: ffffffff8e7aac1a RDI: 00000000ffffffff [ 195.039592] RBP: 0000000000000001 R08: 0000000000000000 R09: ffffbc03c3633a08 [ 195.039593] R10: 0000000000000003 R11: ffffffff8f146328 R12: ffff9b04c42754b0 [ 195.039594] R13: ffffffff8fcc6328 R14: ffffbc03c3633c80 R15: ffff9b0484ab9100 [ 195.039595] FS: 00007fc7aaf68640(0000) GS:ffff9b0bbf7c0000(0000) knlGS:0000000000000000 [ 195.039596] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 195.039597] CR2: 000055d402c49110 CR3: 0000000159392003 CR4: 0000000000772ee0 [ 195.039598] PKRU: 55555554 [ 195.039599] Call Trace: [ 195.039600] <TASK> [ 195.039602] __unmap_hugepage_range+0x33b/0x7d0 [ 195.039605] unmap_hugepage_range+0x55/0x70 [ 195.039608] hugetlb_vmdelete_list+0x77/0xa0 [ 195.039611] hugetlbfs_fallocate+0x410/0x550 [ 195.039612] ? _raw_spin_unlock_irqrestore+0x23/0x40 [ 195.039616] vfs_fallocate+0x12e/0x360 [ 195.039618] __x64_sys_fallocate+0x40/0x70 [ 195.039620] do_syscall_64+0x58/0x80 [ 195.039623] ? syscall_exit_to_user_mode+0x17/0x40 [ 195.039624] ? do_syscall_64+0x67/0x80 [ 195.039626] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 195.039628] RIP: 0033:0x7fc7b590651f [ 195.039653] Code: [...] [ 195.039654] RSP: 002b:00007fc7aaf66e70 EFLAGS: 00000293 ORIG_RAX: 000000000000011d [ 195.039655] RAX: ffffffffffffffda RBX: 0000558ef4b7f370 RCX: 00007fc7b590651f ---truncated---
Source: NVD (National Vulnerability Database)
CVSS Information
N/A
Source: NVD (National Vulnerability Database)
Vulnerability Type
N/A
Source: NVD (National Vulnerability Database)
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于hugetlb_change_protection未正确处理PTE标记。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

VendorProductAffected VersionsCPESubscribe
LinuxLinux 60dfaad65aa97fb6755b9798a6b3c9e79bcd5930 ~ 6062c992e912df1eedad52cf64efb3d48e8d35c5 -
LinuxLinux 5.19 -

II. Public POCs for CVE-2022-49760

#POC DescriptionSource LinkShenlong Link
AI-Generated POCPremium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2022-49760

请登录查看更多情报信息。

Same Patch Batch · Linux · 2025-03-27 · 124 CVEs total

CVE-2023-52982fscache: Use wait_on_bit() to wait for the freeing of relinquished volume
CVE-2023-52998net: fec: Use page_pool_put_full_page when freeing rx buffers
CVE-2023-52999net: fix UaF in netns ops registration error path
CVE-2023-52997ipv4: prevent potential spectre v1 gadget in ip_metrics_convert()
CVE-2023-52996ipv4: prevent potential spectre v1 gadget in fib_metrics_match()
CVE-2023-52995riscv/kprobe: Fix instruction simulation of JALR
CVE-2023-52994acpi: Fix suspend with Xen PV
CVE-2023-52993x86/i8259: Mark legacy PIC interrupts with IRQ_LEVEL
CVE-2023-52992bpf: Skip task with pid=1 in send_signal_common()
CVE-2023-52991net: fix NULL pointer in skb_segment_list
CVE-2023-52989firewire: fix memory leak for payload of request subaction to IEC 61883-1 FCP region
CVE-2023-52988ALSA: hda/via: Avoid potential array out-of-bound in add_secret_dac_path()
CVE-2023-52987ASoC: SOF: ipc4-mtrace: prevent underflow in sof_ipc4_priority_mask_dfs_write()
CVE-2023-52986bpf, sockmap: Check for any of tcp_bpf_prots when cloning a listener
CVE-2023-52985arm64: dts: imx8mm-verdin: Do not power down eth-phy
CVE-2023-52984net: phy: dp83822: Fix null pointer access on DP83825/DP83826 devices
CVE-2023-52973vc_screen: move load of struct vc_data pointer in vcs_read() to avoid UAF
CVE-2022-49761btrfs: always report error in run_one_delayed_ref()
CVE-2022-49759VMCI: Use threaded irqs instead of tasklets
CVE-2023-52974scsi: iscsi_tcp: Fix UAF during login when accessing the shost ipaddress

Showing top 20 of 124 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2022-49760

No comments yet

Leave a comment