CVE-2024-40915riscv: rewrite __kernel_map_pages() to fix sleeping in invalid context
- 5.5MediumCVSS base score
- 0.21%Exploitation in 30 daysEPSS · top 89% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By Linux
Published
- 22 months later
· 22 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.21% · top 89% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Affected products
- affected 5fde3db5eb028b95aeefa1ab192d36800414e8b8 – < 919f8626099d9909b9a9620b05e8c8ab06581876
- affected 5fde3db5eb028b95aeefa1ab192d36800414e8b8 – < 8661a7af04991201640863ad1a0983173f84b5eb
- affected 5fde3db5eb028b95aeefa1ab192d36800414e8b8 – < d5257ceb19d92069195254866421f425aea42915
- affected 5fde3db5eb028b95aeefa1ab192d36800414e8b8 – < fb1cf0878328fe75d47f0aed0a65b30126fcefc4
- affected 5.7
- unaffected < 5.7
- unaffected 6.1.95 – ≤ 6.1.*
- unaffected 6.6.35 – ≤ 6.6.*
- unaffected 6.9.6 – ≤ 6.9.*
- unaffected 6.10 – ≤ *
References
References5
- https://git.kernel.org/stable/c/919f8626099d9909b9a9620b05e8c8ab06581876 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/8661a7af04991201640863ad1a0983173f84b5eb (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/d5257ceb19d92069195254866421f425aea42915 (opens in a new tab)x_transferred
- https://git.kernel.org/stable/c/fb1cf0878328fe75d47f0aed0a65b30126fcefc4 (opens in a new tab)x_transferred
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2024-38726 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2024-40915)Record last updated .