Patch "powerpc/64s: Wire up cpu_show_spectre_v2()" has been added to the 4.9-stable tree
From: <gregkh@linuxfoundation.org>
Date: 2018-06-02 13:36:56
This is a note to let you know that I've just added the patch titled
powerpc/64s: Wire up cpu_show_spectre_v2()
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
powerpc-64s-wire-up-cpu_show_spectre_v2.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let [off-list ref] know about it.
From foo@baz Sat Jun 2 15:29:05 CEST 2018
From: Michael Ellerman <mpe@ellerman.id.au> Date: Sat, 2 Jun 2018 21:09:03 +1000 Subject: powerpc/64s: Wire up cpu_show_spectre_v2() To: gregkh@linuxfoundation.org Cc: stable@vger.kernel.org, linuxppc-dev@ozlabs.org Message-ID: [ref] From: Michael Ellerman <mpe@ellerman.id.au> commit d6fbe1c55c55c6937cbea3531af7da84ab7473c3 upstream. Add a definition for cpu_show_spectre_v2() to override the generic version. This has several permuations, though in practice some may not occur we cater for any combination. The most verbose is: Mitigation: Indirect branch serialisation (kernel only), Indirect branch cache disabled, ori31 speculation barrier enabled We don't treat the ori31 speculation barrier as a mitigation on its own, because it has to be *used* by code in order to be a mitigation and we don't know if userspace is doing that. So if that's all we see we say: Vulnerable, ori31 speculation barrier enabled Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- arch/powerpc/kernel/security.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+)
--- a/arch/powerpc/kernel/security.c
+++ b/arch/powerpc/kernel/security.c@@ -58,3 +58,36 @@ ssize_t cpu_show_spectre_v1(struct devic return sprintf(buf, "Vulnerable\n"); } + +ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, char *buf) +{ + bool bcs, ccd, ori; + struct seq_buf s; + + seq_buf_init(&s, buf, PAGE_SIZE - 1); + + bcs = security_ftr_enabled(SEC_FTR_BCCTRL_SERIALISED); + ccd = security_ftr_enabled(SEC_FTR_COUNT_CACHE_DISABLED); + ori = security_ftr_enabled(SEC_FTR_SPEC_BAR_ORI31); + + if (bcs || ccd) { + seq_buf_printf(&s, "Mitigation: "); + + if (bcs) + seq_buf_printf(&s, "Indirect branch serialisation (kernel only)"); + + if (bcs && ccd) + seq_buf_printf(&s, ", "); + + if (ccd) + seq_buf_printf(&s, "Indirect branch cache disabled"); + } else + seq_buf_printf(&s, "Vulnerable"); + + if (ori) + seq_buf_printf(&s, ", ori31 speculation barrier enabled"); + + seq_buf_printf(&s, "\n"); + + return s.len; +}
Patches currently in stable-queue which might be from mpe@ellerman.id.au are queue-4.9/powerpc-64s-clear-pcr-on-boot.patch queue-4.9/powerpc-rfi-flush-differentiate-enabled-and-patched-flush-types.patch queue-4.9/powerpc-64s-fix-section-mismatch-warnings-from-setup_rfi_flush.patch queue-4.9/powerpc-pseries-fix-clearing-of-security-feature-flags.patch queue-4.9/powerpc-powernv-set-or-clear-security-feature-flags.patch queue-4.9/powerpc-64s-move-cpu_show_meltdown.patch queue-4.9/powerpc-rfi-flush-call-setup_rfi_flush-after-lpm-migration.patch queue-4.9/powerpc-pseries-set-or-clear-security-feature-flags.patch queue-4.9/powerpc-rfi-flush-make-it-possible-to-call-setup_rfi_flush-again.patch queue-4.9/powerpc-move-default-security-feature-flags.patch queue-4.9/powerpc-powernv-use-the-security-flags-in-pnv_setup_rfi_flush.patch queue-4.9/powerpc-add-security-feature-flags-for-spectre-meltdown.patch queue-4.9/powerpc-pseries-use-the-security-flags-in-pseries_setup_rfi_flush.patch queue-4.9/powerpc-64s-enhance-the-information-in-cpu_show_meltdown.patch queue-4.9/powerpc-rfi-flush-move-out-of-hardlockup_detector-ifdef.patch queue-4.9/powerpc-rfi-flush-always-enable-fallback-flush-on-pseries.patch queue-4.9/powerpc-rfi-flush-move-the-logic-to-avoid-a-redo-into-the-debugfs-code.patch queue-4.9/powerpc-pseries-restore-default-security-feature-flags-on-setup.patch queue-4.9/powerpc-pseries-add-new-h_get_cpu_characteristics-flags.patch queue-4.9/powerpc-64s-add-support-for-a-store-forwarding-barrier-at-kernel-entry-exit.patch queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v1.patch queue-4.9/powerpc-powernv-support-firmware-disable-of-rfi-flush.patch queue-4.9/powerpc-pseries-support-firmware-disable-of-rfi-flush.patch queue-4.9/powerpc-64s-wire-up-cpu_show_spectre_v2.patch