CVE-2025-39686
published 2025-09-05CVE-2025-39686: In the Linux kernel, the following vulnerability has been resolved: comedi: Make insn_rw_emulate_bits() do insn->n samples The `insn_rw_emulate_bits()`…
high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
In the Linux kernel, the following vulnerability has been resolved:
comedi: Make insn_rw_emulate_bits() do insn->n samples
The `insn_rw_emulate_bits()` function is used as a default handler for
`INSN_READ` instructions for subdevices that have a handler for
`INSN_BITS` but not for `INSN_READ`. Similarly, it is used as a default
handler for `INSN_WRITE` instructions for subdevices that have a handler
for `INSN_BITS` but not for `INSN_WRITE`. It works by emulating the
`INSN_READ` or `INSN_WRITE` instruction handling with a constructed
`INSN_BITS` instruction. However, `INSN_READ` and `INSN_WRITE`
instructions are supposed to be able read or write multiple samples,
indicated by the `insn->n` value, but `insn_rw_emulate_bits()` currently
only handles a single sample. For `INSN_READ`, the comedi core will
copy `insn->n` samples back to user-space. (That triggered KASAN
kernel-infoleak errors when `insn->n` was greater than 1, but that is
being fixed more generally elsewhere in the comedi core.)
Make `insn_rw_emulate_bits()` either handle `insn->n` samples, or return
an error, to conform to the general expectation for `INSN_READ` and
`INSN_WRITE` handlers.
Affected
33 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | linux | < linux 6.1.153-1 (bookworm) | linux 6.1.153-1 (bookworm) |
| debian | linux-6.1 | < linux 6.1.153-1 (bookworm) | linux 6.1.153-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= ed9eccbe8970f6eedc1b978c157caf1251a896d4 < ab77e85bd3bc006ef40738f26f446a660813da44 | ab77e85bd3bc006ef40738f26f446a660813da44 |
| linux | linux | >= ed9eccbe8970f6eedc1b978c157caf1251a896d4 < ae8bc1f07bcb31b8636420e03d1f9c3df6219a2b | ae8bc1f07bcb31b8636420e03d1f9c3df6219a2b |
| linux | linux | >= ed9eccbe8970f6eedc1b978c157caf1251a896d4 < 842f307a1d115b24f2bcb2415c4e344f11f55930 | 842f307a1d115b24f2bcb2415c4e344f11f55930 |
| linux | linux | >= ed9eccbe8970f6eedc1b978c157caf1251a896d4 < 92352ed2f9ac422181e381c2430c2d0dfb46faa0 | 92352ed2f9ac422181e381c2430c2d0dfb46faa0 |
| linux | linux | >= ed9eccbe8970f6eedc1b978c157caf1251a896d4 < dc0a2f142d655700db43de90cb6abf141b73d908 | dc0a2f142d655700db43de90cb6abf141b73d908 |
| linux | linux | >= ed9eccbe8970f6eedc1b978c157caf1251a896d4 < 7afba9221f70d4cbce0f417c558879cba0eb5e66 | 7afba9221f70d4cbce0f417c558879cba0eb5e66 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 6.1.153-1 | 6.1.153-1 |
| linux | linux_kernel | >= 0 < 6.12.48-1 | 6.12.48-1 |
| linux | linux_kernel | >= 0 < 6.16.5-1 | 6.16.5-1 |
| linux | linux_kernel | >= 0 < 5.15.0-163.173 | 5.15.0-163.173 |
| linux | linux_kernel | >= 0 < 6.8.0-100.100 | 6.8.0-100.100 |
| linux | linux_kernel | >= 2.6.29 < 5.15.190 | 5.15.190 |
| linux | linux_kernel | >= 5.16 < 6.1.149 | 6.1.149 |
| linux | linux_kernel | >= 6.13 < 6.16.4 | 6.16.4 |
| linux | linux_kernel | >= 6.2 < 6.6.103 | 6.6.103 |
| linux | linux_kernel | >= 6.7 < 6.12.44 | 6.12.44 |
| msrc | azl3_kernel_6.6.96.2-1_on_azure_linux_3.0 | — | — |
| msrc | azl3_kernel_6.6.96.2-2_on_azure_linux_3.0 | — | — |
| msrc | cbl2_kernel_5.15.186.1-1_on_cbl_mariner_2.0 | — | — |
| ubuntu | linux-aws | — | — |
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