Summary
In the Linux kernel, the following vulnerability has been resolved: LoongArch: Set hugetlb mmap...
In the Linux kernel, the following vulnerability has been resolved:
LoongArch: Set hugetlb mmap base address aligned with pmd size
With ltp test case "testcases/bin/hugefork02", there is a dmesg error
report message such as:
kernel BUG at mm/hugetlb.c:5550!
Oops - BUG[#1]:
CPU: 0 UID: 0 PID: 1517 Comm: hugefork02 Not tainted 6.14.0-rc2+ #241
Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 2/2/2022
pc 90000000004eaf1c ra 9000000000485538 tp 900000010edbc000 sp 900000010edbf940
a0 900000010edbfb00 a1 9000000108d20280 a2 00007fffe9474000 a3 00007ffff3474000
a4 0000000000000000 a5 0000000000000003 a6 00000000003cadd3 a7 0000000000000000
t0 0000000001ffffff t1 0000000001474000 t2 900000010ecd7900 t3 00007fffe9474000
t4 00007fffe9474000 t5 0000000000000040 t6 900000010edbfb00 t7 0000000000000001
t8 0000000000000005 u0 90000000004849d0 s9 900000010edbfa00 s0 9000000108d20280
s1 00007fffe9474000 s2 0000000002000000 s3 9000000108d20280 s4 9000000002b38b10
s5 900000010edbfb00 s6 00007ffff3474000 s7 0000000000000406 s8 900000010edbfa08
ra: 9000000000485538 unmap_vmas+0x130/0x218
ERA: 90000000004eaf1c __unmap_hugepage_range+0x6f4/0x7d0
PRMD: 00000004 (PPLV0 +PIE -PWE)
EUEN: 00000007 (+FPE +SXE +ASXE -BTE)
ECFG: 00071c1d (LIE=0,2-4,10-12 VS=7)
ESTAT: 000c0000 [BRK] (IS= ECode=12 EsubCode=0)
PRID: 0014c010 (Loongson-64bit, Loongson-3A5000)
Process hugefork02 (pid: 1517, threadinfo=00000000a670eaf4, task=000000007a95fc64)
Call Trace:
[<90000000004eaf1c>] __unmap_hugepage_range+0x6f4/0x7d0
[<9000000000485534>] unmap_vmas+0x12c/0x218
[<9000000000494068>] exit_mmap+0xe0/0x308
[<900000000025fdc4>] mmput+0x74/0x180
[<900000000026a284>] do_exit+0x294/0x898
[<900000000026aa30>] do_group_exit+0x30/0x98
[<900000000027bed4>] get_signal+0x83c/0x868
[<90000000002457b4>] arch_do_signal_or_restart+0x54/0xfa0
[<90000000015795e8>] irqentry_exit_to_user_mode+0xb8/0x138
[<90000000002572d0>] tlb_do_page_fault_1+0x114/0x1b4
The problem is that base address allocated from hugetlbfs is not aligned
with pmd size. Here add a checking for hugetlbfs and align base address
with pmd size. After this patch the test case "testcases/bin/hugefork02"
passes to run.
This is similar to the commit 7f24cbc9c4d42db8a3c8484d1 ("mm/mmap: teach
generic_get_unmapped_area{_topdown} to handle hugetlb mappings").
Impact
CVE-2025-21949 has a CVSS score of 5.5 (Medium). The vector is requires local access, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. No fixed version is listed yet, so configuration controls and monitoring matter more in the interim.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2025-21949? CVE-2025-21949 is a medium-severity security vulnerability. No fixed version is listed yet.
- How severe is CVE-2025-21949? CVE-2025-21949 has a CVSS score of 5.5 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Is there a fix for CVE-2025-21949? No fixed version is listed for CVE-2025-21949 yet. Monitor the advisory for updates and apply mitigations in the interim.
- Is CVE-2025-21949 exploitable, and should I be worried? Whether CVE-2025-21949 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-21949 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.