CVE-2025-38255
CVE.org · Published
- Record status
- Published
- Identifier year (not publication year)
- 2025
- Source publication
- Source updated
- Imported by cveboard
- Source snapshot
- cve_2026-10-24_midnight_baseline ·
CNA source text (English)
lib/group_cpus: fix NULL pointer dereference from group_cpus_evenly()
In the Linux kernel, the following vulnerability has been resolved: lib/group_cpus: fix NULL pointer dereference from group_cpus_evenly() While testing null_blk with configfs, echo 0 > poll_queues will trigger following panic: BUG: kernel NULL pointer dereference, address: 0000000000000010 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 27 UID: 0 PID: 920 Comm: bash Not tainted 6.15.0-02023-gadbdb95c8696-dirty #1238 PREEMPT(undef) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:__bitmap_or+0x48/0x70 Call Trace: <TASK> __group_cpus_evenly+0x822/0x8c0 group_cpus_evenly+0x2d9/0x490 blk_mq_map_queues+0x1e/0x110 null_map_queues+0xc9/0x170 [null_blk] blk_mq_update_queue_map+0xdb/0x160 blk_mq_update_nr_hw_queues+0x22b/0x560 nullb_update_nr_hw_queues+0x71/0xf0 [null_blk] nullb_device_poll_queues_store+0xa4/0x130 [null_blk] configfs_write_iter+0x109/0x1d0 vfs_write+0x26e/0x6f0 ksys_write+0x79/0x180 __x64_sys_write+0x1d/0x30 x64_sys_call+0x45c4/0x45f0 do_syscall_64+0xa5/0x240 entry_SYSCALL_64_after_hwframe+0x76/0x7e Root cause is that numgrps is set to 0, and ZERO_SIZE_PTR is returned from kcalloc(), and later ZERO_SIZE_PTR will be deferenced. Fix the problem by checking numgrps first in group_cpus_evenly(), and return NULL directly if numgrps is zero. [yukuai3@huawei.com: also fix the non-SMP version]
Scoped product and version facts
Fix information unknown; no fixed version is derived here. Missing information does not prove that no fix exists.
Exploitation unknown; this catalogue does not assess exploitation.
Linux
- Vendor
- Linux
- Product
- Linux
- Platforms
- Unknown
- Default status
unaffected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 6a6dcae8f486c3f3298d0767d34505121c7b0b81 | affected | git | 64a99eff8dcf1f951a544e6058341b2b19a8fdbd | Unavailable | None listed |
| 6a6dcae8f486c3f3298d0767d34505121c7b0b81 | affected | git | 29d39e0d5f16c060e32542b2cf351c09fd22b250 | Unavailable | None listed |
| 6a6dcae8f486c3f3298d0767d34505121c7b0b81 | affected | git | 911ef2e8a7de5b2bae8ff11fb0bd01f699e6db65 | Unavailable | None listed |
| 6a6dcae8f486c3f3298d0767d34505121c7b0b81 | affected | git | df831e97739405ecbaddb85516bc7d4d1c933d6b | Unavailable | None listed |
Linux
- Vendor
- Linux
- Product
- Linux
- Platforms
- Unknown
- Default status
affected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 6.3 | affected | Unavailable | Unavailable | Unavailable | None listed |
| 0 | unaffected | semver | 6.3 | Unavailable | None listed |
| 6.6.96 | unaffected | semver | Unavailable | 6.6.* | None listed |
| 6.12.36 | unaffected | semver | Unavailable | 6.12.* | None listed |
| 6.15.5 | unaffected | semver | Unavailable | 6.15.* | None listed |
| 6.16 | unaffected | original_commit_for_fix | Unavailable | * | None listed |