CVE-2025-40112
Published: November 14, 2025Last modified: June 24, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: sparc: fix accurate exception reporting in copy_{from_to}_user for Niagara The referenced commit introduced exception handlers on user-space memory references in copy_from_user and copy_to_user. These handlers return from the respective function and calculate the remaining bytes left to copy using the current register contents. This commit fixes a couple of bad calculations and a broken epilogue in the exception handlers. This will prevent crashes and ensure correct return values of copy_from_user and copy_to_user in the faulting case. The behaviour of memcpy stays unchanged.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.8 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Fixed (6.1.156-r0) |
| 25 LTS | linux-lts | Fixed (6.12.53-r0) | |
| Stream | linux-lts | Fixed (6.18.35-r1) |
References
- https://git.kernel.org/stable/c/05440320ea3e249d5f984918f2bf51210c1a7c03
- https://git.kernel.org/stable/c/088c5098ec6d6b0396edfbf3dad3e81de8469c1c
- https://git.kernel.org/stable/c/0b67c8fc10b13a9090340c5f8a37d308f4e1571c
- https://git.kernel.org/stable/c/37547d8e6eba87507279ee3dfddfd9dc46335454
- https://git.kernel.org/stable/c/7823fc4d8ab5e57f8db7806ff2530c03c166c4bb
- https://git.kernel.org/stable/c/8cdeb5e482d3fdce7e825444b6ca3865e24c0228
- https://git.kernel.org/stable/c/a365ee556e45f780ee322b349a06efdad0c1458f
- https://git.kernel.org/stable/c/a90ce516a73dbe087f9bf3dbf311301a58d125c6