cbcvebase.
CVE-2025-40124
published 2025-11-12

CVE-2025-40124: In the Linux kernel, the following vulnerability has been resolved: sparc: fix accurate exception reporting in copy_{from_to}_user for UltraSPARC III Anthony…

PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.15%
4.8th percentile
In the Linux kernel, the following vulnerability has been resolved: sparc: fix accurate exception reporting in copy_{from_to}_user for UltraSPARC III Anthony Yznaga tracked down that a BUG_ON in ext4 code with large folios enabled resulted from copy_from_user() returning impossibly large values greater than the size to be copied. This lead to __copy_from_iter() returning impossible values instead of the actual number of bytes it was able to copy. The BUG_ON has been reported in https://lore.kernel.org/r/b14f55642207e63e907965e209f6323a0df6dcee.camel@physik.fu-berlin.de 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. The exception handlers expect that %o2 has already been masked during the bulk copy loop, but the masking was performed after that loop. This will fix the return value of copy_from_user and copy_to_user in the faulting case. The behaviour of memcpy stays unchanged.

Affected

34 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.158-1 (bookworm)linux 6.1.158-1 (bookworm)
debianlinux-6.1< linux 6.1.158-1 (bookworm)linux 6.1.158-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux
linuxlinux>= 4.4.34 < 4.54.5
linuxlinux>= 4.8.10 < 4.94.9
linuxlinux>= ee841d0aff649164080e445e84885015958d8ff4 < fdd43fe6d286f27b826572457a89c926f97e2d3afdd43fe6d286f27b826572457a89c926f97e2d3a
linuxlinux>= ee841d0aff649164080e445e84885015958d8ff4 < 1198077606aeffb102587c6ea079ce99641c99d41198077606aeffb102587c6ea079ce99641c99d4
linuxlinux>= ee841d0aff649164080e445e84885015958d8ff4 < 1857cdca12c4aff58bf26a7005a4d02850c299271857cdca12c4aff58bf26a7005a4d02850c29927
linuxlinux>= ee841d0aff649164080e445e84885015958d8ff4 < 91eda032eb16e5d2be27c95584665bc555bb5a9091eda032eb16e5d2be27c95584665bc555bb5a90
linuxlinux>= ee841d0aff649164080e445e84885015958d8ff4 < dc766c4830a7e1e1ee9d7f77d4ab344f2eb23c8edc766c4830a7e1e1ee9d7f77d4ab344f2eb23c8e
linuxlinux>= ee841d0aff649164080e445e84885015958d8ff4 < 5ef9c94d7110e90260c06868cf1dcf899b9f25ee5ef9c94d7110e90260c06868cf1dcf899b9f25ee
linuxlinux>= ee841d0aff649164080e445e84885015958d8ff4 < e50377c6b3f278c9f3ef017ffce17f5fcc9dace4e50377c6b3f278c9f3ef017ffce17f5fcc9dace4
linuxlinux>= ee841d0aff649164080e445e84885015958d8ff4 < 47b49c06eb62504075f0f2e2227aee2e2c2a58b347b49c06eb62504075f0f2e2227aee2e2c2a58b3
linuxlinux_kernel>= 0 < 6.1.158-16.1.158-1
linuxlinux_kernel>= 0 < 6.12.57-16.12.57-1
linuxlinux_kernel>= 0 < 6.17.6-16.17.6-1
linuxlinux_kernel>= 0 < 5.15.0-170.1805.15.0-170.180
linuxlinux_kernel>= 0 < 6.8.0-106.1066.8.0-106.106
linuxlinux_kernel>= 0 < 6.17.0-14.146.17.0-14.14
linuxlinux_kernel>= 4.9.0 < 5.4.3015.4.301
linuxlinux_kernel>= 5.11.0 < 5.15.1955.15.195
linuxlinux_kernel>= 5.16.0 < 6.1.1566.1.156
linuxlinux_kernel>= 5.5.0 < 5.10.2465.10.246

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_ubuntu7.8HIGH
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