4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Kees Cook <keescook@xxxxxxxxxxxx>
commit fae1fa0fc6cca8beee3ab8ed71d54f9a78fa3f64 upstream
As done with seccomp and no_new_privs, also show speculation flaw
mitigation state in /proc/$pid/status.
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Srivatsa S. Bhat <srivatsa@xxxxxxxxxxxxx>
Reviewed-by: Matt Helsley (VMware) <matt.helsley@xxxxxxxxx>
Reviewed-by: Alexey Makhalov <amakhalov@xxxxxxxxxx>
Reviewed-by: Bo Gan <ganb@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/proc/array.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -79,6 +79,7 @@
#include <linux/delayacct.h>
#include <linux/seq_file.h>
#include <linux/pid_namespace.h>
+#include <linux/prctl.h>
#include <linux/ptrace.h>
#include <linux/tracehook.h>
#include <linux/string_helpers.h>
@@ -332,6 +333,28 @@ static inline void task_seccomp(struct s
#ifdef CONFIG_SECCOMP
seq_printf(m, "Seccomp:\t%d\n", p->seccomp.mode);
#endif
+ seq_printf(m, "\nSpeculation Store Bypass:\t");
+ switch (arch_prctl_spec_ctrl_get(p, PR_SPEC_STORE_BYPASS)) {
+ case -EINVAL:
+ seq_printf(m, "unknown");
+ break;
+ case PR_SPEC_NOT_AFFECTED:
+ seq_printf(m, "not vulnerable");
+ break;
+ case PR_SPEC_PRCTL | PR_SPEC_DISABLE:
+ seq_printf(m, "thread mitigated");
+ break;
+ case PR_SPEC_PRCTL | PR_SPEC_ENABLE:
+ seq_printf(m, "thread vulnerable");
+ break;
+ case PR_SPEC_DISABLE:
+ seq_printf(m, "globally mitigated");
+ break;
+ default:
+ seq_printf(m, "vulnerable");
+ break;
+ }
+ seq_putc(m, '\n');
}
static inline void task_context_switch_counts(struct seq_file *m,
