In the Linux kernel, the following vulnerability has been resolved:

riscv: rewrite __kernel_map_pages() to fix sleeping in invalid context

__kernel_map_pages() is a debug function which clears the valid bit in page
table entry for deallocated pages to detect illegal memory accesses to
freed pages.

This function set/clear the valid bit using __set_memory(). __set_memory()
acquires init_mm's semaphore, and this operation may sleep. This is
problematic, because __kernel_map_pages() can be called in atomic context,
and thus is illegal to sleep. An example warning that this causes:

BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1578
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2, name: kthreadd
preempt_count: 2, expected: 0
CPU: 0 PID: 2 Comm: kthreadd Not tainted 6.9.0-g1d4c6d784ef6 #37
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
[<ffffffff800060dc>] dump_backtrace+0x1c/0x24
[<ffffffff8091ef6e>] show_stack+0x2c/0x38
[<ffffffff8092baf8>] dump_stack_lvl+0x5a/0x72
[<ffffffff8092bb24>] dump_stack+0x14/0x1c
[<ffffffff8003b7ac>] __might_resched+0x104/0x10e
[<ffffffff8003b7f4>] __might_sleep+0x3e/0x62
[<ffffffff8093276a>] down_write+0x20/0x72
[<ffffffff8000cf00>] __set_memory+0x82/0x2fa
[<ffffffff8000d324>] __kernel_map_pages+0x5a/0xd4
[<ffffffff80196cca>] __alloc_pages_bulk+0x3b2/0x43a
[<ffffffff8018ee82>] __vmalloc_node_range+0x196/0x6ba
[<ffffffff80011904>] copy_process+0x72c/0x17ec
[<ffffffff80012ab4>] kernel_clone+0x60/0x2fe
[<ffffffff80012f62>] kernel_thread+0x82/0xa0
[<ffffffff8003552c>] kthreadd+0x14a/0x1be
[<ffffffff809357de>] ret_from_fork+0xe/0x1c

Rewrite this function with apply_to_existing_page_range(). It is fine to
not have any locking, because __kernel_map_pages() works with pages being
allocated/deallocated and those pages are not changed by anyone else in the
meantime.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 17 Sep 2025 15:45:00 +0000

Type Values Removed Values Added
Weaknesses CWE-667
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Metrics cvssV3_1

{'score': 4.1, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H'}

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}


Wed, 11 Sep 2024 13:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-05-04T09:17:44.435Z

Reserved: 2024-07-12T12:17:45.581Z

Link: CVE-2024-40915

cve-icon Vulnrichment

Updated: 2024-09-11T12:42:25.005Z

cve-icon NVD

Status : Analyzed

Published: 2024-07-12T13:15:14.660

Modified: 2025-09-17T15:32:56.787

Link: CVE-2024-40915

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-07-12T00:00:00Z

Links: CVE-2024-40915 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2025-07-13T21:07:50Z