@@ -117,25 +117,35 @@ ssize_t cpu_show_meltdown(struct device *dev, struct device_attribute *attr, cha
ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, char *buf)
{
- if (!security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR))
- return sprintf(buf, "Not affected\n");
+ struct seq_buf s;
+
+ seq_buf_init(&s, buf, PAGE_SIZE - 1);
- if (barrier_nospec_enabled)
- return sprintf(buf, "Mitigation: __user pointer sanitization\n");
+ if (security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR)) {
+ if (barrier_nospec_enabled)
+ seq_buf_printf(&s, "Mitigation: __user pointer sanitization");
+ else
+ seq_buf_printf(&s, "Vulnerable");
- return sprintf(buf, "Vulnerable\n");
+ if (security_ftr_enabled(SEC_FTR_SPEC_BAR_ORI31))
+ seq_buf_printf(&s, ", ori31 speculation barrier enabled");
+
+ seq_buf_printf(&s, "\n");
+ } else
+ seq_buf_printf(&s, "Not affected\n");
+
+ return s.len;
}
ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, char *buf)
{
- bool bcs, ccd, ori;
struct seq_buf s;
+ bool bcs, ccd;
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: ");
@@ -151,9 +161,6 @@ ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, c
} else
seq_buf_printf(&s, "Vulnerable");
- if (ori)
- seq_buf_printf(&s, ", ori31 speculation barrier enabled");
-
seq_buf_printf(&s, "\n");
return s.len;
When I added the spectre_v2 information in sysfs, I included the availability of the ori31 speculation barrier. Although the ori31 barrier can be used to mitigate v2, it's primarily intended as a spectre v1 mitigation. Spectre v2 is mitigated by hardware changes. So rework the sysfs files to show the ori31 information in the spectre_v1 file, rather than v2. Currently we display eg: $ grep . spectre_v* spectre_v1:Mitigation: __user pointer sanitization spectre_v2:Mitigation: Indirect branch cache disabled, ori31 speculation barrier enabled After: $ grep . spectre_v* spectre_v1:Mitigation: __user pointer sanitization, ori31 speculation barrier enabled spectre_v2:Mitigation: Indirect branch cache disabled Fixes: d6fbe1c55c55 ("powerpc/64s: Wire up cpu_show_spectre_v2()") Cc: stable@vger.kernel.org # v4.17+ Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> --- arch/powerpc/kernel/security.c | 27 +++++++++++++++++---------- 1 file changed, 17 insertions(+), 10 deletions(-)