CVE-2022-50206
Severity CVSS v4.0:
Pending analysis
Type:
Unavailable / Other
Publication date:
18/06/2025
Last modified:
18/06/2025
Description
In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
arm64: fix oops in concurrently setting insn_emulation sysctls<br />
<br />
emulation_proc_handler() changes table->data for proc_dointvec_minmax<br />
and can generate the following Oops if called concurrently with itself:<br />
<br />
| Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010<br />
| Internal error: Oops: 96000006 [#1] SMP<br />
| Call trace:<br />
| update_insn_emulation_mode+0xc0/0x148<br />
| emulation_proc_handler+0x64/0xb8<br />
| proc_sys_call_handler+0x9c/0xf8<br />
| proc_sys_write+0x18/0x20<br />
| __vfs_write+0x20/0x48<br />
| vfs_write+0xe4/0x1d0<br />
| ksys_write+0x70/0xf8<br />
| __arm64_sys_write+0x20/0x28<br />
| el0_svc_common.constprop.0+0x7c/0x1c0<br />
| el0_svc_handler+0x2c/0xa0<br />
| el0_svc+0x8/0x200<br />
<br />
To fix this issue, keep the table->data as &insn->current_mode and<br />
use container_of() to retrieve the insn pointer. Another mutex is<br />
used to protect against the current_mode update but not for retrieving<br />
insn_emulation as table->data is no longer changing.
Impact
References to Advisories, Solutions, and Tools
- https://git.kernel.org/stable/c/04549063d5701976034d8c2bfda3d3a8cbf0409f
- https://git.kernel.org/stable/c/07022e07017ee5540f5559b0aeb916e8383c1e1a
- https://git.kernel.org/stable/c/353b4673d01c512303c45cf2346f630cda73b5c9
- https://git.kernel.org/stable/c/6a2fd114678d7fc1b5a0f8865ae98f1c17787455
- https://git.kernel.org/stable/c/9d5fec6ba2e4117d196a8259ab54615ffe562460
- https://git.kernel.org/stable/c/af483947d472eccb79e42059276c4deed76f99a6
- https://git.kernel.org/stable/c/b51881b1da57fe9877125dfdd0aac5172958fcfd
- https://git.kernel.org/stable/c/cc69ef95988b9ef2fc730ec452a7441efb90ef5e