Description (CNA)
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 (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected ee841d0aff649164080e445e84885015958d8ff4 before fdd43fe6d286f27b826572457a89c926f97e2d3a; affected ee841d0aff649164080e445e84885015958d8ff4 before 1198077606aeffb102587c6ea079ce99641c99d4; affected ee841d0aff649164080e445e84885015958d8ff4 before 1857cdca12c4aff58bf26a7005a4d02850c29927; affected ee841d0aff649164080e445e84885015958d8ff4 before 91eda032eb16e5d2be27c95584665bc555bb5a90; affected ee841d0aff649164080e445e84885015958d8ff4 before dc766c4830a7e1e1ee9d7f77d4ab344f2eb23c8e; affected ee841d0aff649164080e445e84885015958d8ff4 before 5ef9c94d7110e90260c06868cf1dcf899b9f25ee; affected ee841d0aff649164080e445e84885015958d8ff4 before e50377c6b3f278c9f3ef017ffce17f5fcc9dace4; affected ee841d0aff649164080e445e84885015958d8ff4 before 47b49c06eb62504075f0f2e2227aee2e2c2a58b3; affected 1c7e17b1c4d60cc5aa575460f7efb73686dd3b39; affected ac663c54f40b2830b1ca32d1ae9d683fe248b14c; affected 4.4.34 before 4.5; affected 4.8.10 before 4.9 |
| Linux / Linux | affected 4.9; unaffected 0 before 4.9; unaffected 5.4.301 through 5.4.*; unaffected 5.10.246 through 5.10.*; unaffected 5.15.195 through 5.15.*; unaffected 6.1.156 through 6.1.*; unaffected 6.6.112 through 6.6.*; unaffected 6.12.53 through 6.12.*; unaffected 6.17.3 through 6.17.*; unaffected 6.18 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/fdd43fe6d286f27b826572457a89c926f97e2d3a
- https://git.kernel.org/stable/c/1198077606aeffb102587c6ea079ce99641c99d4
- https://git.kernel.org/stable/c/1857cdca12c4aff58bf26a7005a4d02850c29927
- https://git.kernel.org/stable/c/91eda032eb16e5d2be27c95584665bc555bb5a90
- https://git.kernel.org/stable/c/dc766c4830a7e1e1ee9d7f77d4ab344f2eb23c8e
- https://git.kernel.org/stable/c/5ef9c94d7110e90260c06868cf1dcf899b9f25ee
- https://git.kernel.org/stable/c/e50377c6b3f278c9f3ef017ffce17f5fcc9dace4
- https://git.kernel.org/stable/c/47b49c06eb62504075f0f2e2227aee2e2c2a58b3