Описание
In the Linux kernel, the following vulnerability has been resolved:
x86/fpu: Ensure XFD state on signal delivery
Sean reported [1] the following splat when running KVM tests:
WARNING: CPU: 232 PID: 15391 at xfd_validate_state+0x65/0x70 Call Trace: fpu__clear_user_states+0x9c/0x100 arch_do_signal_or_restart+0x142/0x210 exit_to_user_mode_loop+0x55/0x100 do_syscall_64+0x205/0x2c0 entry_SYSCALL_64_after_hwframe+0x4b/0x53
Chao further identified [2] a reproducible scenario involving signal delivery: a non-AMX task is preempted by an AMX-enabled task which modifies the XFD MSR.
When the non-AMX task resumes and reloads XSTATE with init values, a warning is triggered due to a mismatch between fpstate::xfd and the CPU's current XFD state. fpu__clear_user_states() does not currently re-synchronize the XFD state after such preemption.
Invoke xfd_update_state() which detects and corrects the mismatch if there is a dynamic feature.
This also benefits ...
In the Linux kernel, the following vulnerability has been resolved:
x86/fpu: Ensure XFD state on signal delivery
Sean reported [1] the following splat when running KVM tests:
WARNING: CPU: 232 PID: 15391 at xfd_validate_state+0x65/0x70 Call Trace: fpu__clear_user_states+0x9c/0x100 arch_do_signal_or_restart+0x142/0x210 exit_to_user_mode_loop+0x55/0x100 do_syscall_64+0x205/0x2c0 entry_SYSCALL_64_after_hwframe+0x4b/0x53
Chao further identified [2] a reproducible scenario involving signal delivery: a non-AMX task is preempted by an AMX-enabled task which modifies the XFD MSR.
When the non-AMX task resumes and reloads XSTATE with init values, a warning is triggered due to a mismatch between fpstate::xfd and the CPU's current XFD state. fpu__clear_user_states() does not currently re-synchronize the XFD state after such preemption.
Invoke xfd_update_state() which detects and corrects the mismatch if there is a dynamic feature.
This also benefits the sigreturn path, as fpu__restore_sig() may call fpu__clear_user_states() when the sigframe is inaccessible.
[ dhansen: minor changelog munging ]
Ссылки
- https://nvd.nist.gov/vuln/detail/CVE-2025-68171
- https://git.kernel.org/stable/c/1811c610653c0cd21cc9add14595b7cffaeca511
- https://git.kernel.org/stable/c/388eff894d6bc5f921e9bfff0e4b0ab2684a96e9
- https://git.kernel.org/stable/c/3f735419c4b43cde42e6d408db39137b82474e31
- https://git.kernel.org/stable/c/5b2619b488f1d08b960c43c6468dd0759e8b3035
- https://git.kernel.org/stable/c/eefbfb722042fc9210d2e0ac2b063fd1abf51895
EPSS
CVE ID
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: x86/fpu: Ensure XFD state on signal delivery Sean reported [1] the following splat when running KVM tests: WARNING: CPU: 232 PID: 15391 at xfd_validate_state+0x65/0x70 Call Trace: <TASK> fpu__clear_user_states+0x9c/0x100 arch_do_signal_or_restart+0x142/0x210 exit_to_user_mode_loop+0x55/0x100 do_syscall_64+0x205/0x2c0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Chao further identified [2] a reproducible scenario involving signal delivery: a non-AMX task is preempted by an AMX-enabled task which modifies the XFD MSR. When the non-AMX task resumes and reloads XSTATE with init values, a warning is triggered due to a mismatch between fpstate::xfd and the CPU's current XFD state. fpu__clear_user_states() does not currently re-synchronize the XFD state after such preemption. Invoke xfd_update_state() which detects and corrects the mismatch if there is a dynamic feature. This also benefits the sigreturn path, as fpu__restore_s...
In the Linux kernel, the following vulnerability has been resolved: x86/fpu: Ensure XFD state on signal delivery Sean reported [1] the following splat when running KVM tests: WARNING: CPU: 232 PID: 15391 at xfd_validate_state+0x65/0x70 Call Trace: <TASK> fpu__clear_user_states+0x9c/0x100 arch_do_signal_or_restart+0x142/0x210 exit_to_user_mode_loop+0x55/0x100 do_syscall_64+0x205/0x2c0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Chao further identified [2] a reproducible scenario involving signal delivery: a non-AMX task is preempted by an AMX-enabled task which modifies the XFD MSR. When the non-AMX task resumes and reloads XSTATE with init values, a warning is triggered due to a mismatch between fpstate::xfd and the CPU's current XFD state. fpu__clear_user_states() does not currently re-synchronize the XFD state after such preemption. Invoke xfd_update_state() which detects and corrects the mismatch if there is a dynamic feature. This also benefits the
In the Linux kernel, the following vulnerability has been resolved: x ...
ELSA-2026-50006: Unbreakable Enterprise kernel security update (IMPORTANT)
EPSS