On Wed, Jan 16, 2019 at 10:58 AM Guenter Roeck linux@roeck-us.net wrote:

If CONFIG_SECCOMP=n, /proc/self/status includes an empty line. This causes the iotop application to bail out with an error message.

File "/usr/local/lib64/python2.7/site-packages/iotop/data.py", line 196, in parse_proc_pid_status key, value = line.split(':\t', 1) ValueError: need more than 1 value to unpack

The problem is seen in v4.9.y but not upstream because commit af884cd4a5ae6 ("proc: report no_new_privs state") has not been backported to v4.9.y. The backport of commit fae1fa0fc6cc ("proc: Provide details on speculation flaw mitigations") tried to address the resulting differences but was wrong, introducing the problem.

Fixes: 51ef9af2a35b ("proc: Provide details on speculation flaw mitigations") Cc: Kees Cook keescook@chromium.org Cc: Gwendal Grignou gwendal@chromium.org Signed-off-by: Guenter Roeck linux@roeck-us.net

Acked-by: Kees Cook keescook@chromium.org

-Kees

---

This patch only applies to v4.9.y. v4.4.y also needs to be fixed (see https://www.spinics.net/lists/stable/msg279131.html), but the fix is slightly different. v4.14.y and later are not affected.

fs/proc/array.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/proc/array.c b/fs/proc/array.c index 94f83e74db24..712b44c63701 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -346,8 +346,9 @@ static inline void task_seccomp(struct seq_file *m, struct task_struct *p) { #ifdef CONFIG_SECCOMP seq_put_decimal_ull(m, "Seccomp:\t", p->seccomp.mode);

•   seq_putc(m, '\n');
  

#endif

•   seq_printf(m, "\nSpeculation_Store_Bypass:\t");
  

•   seq_printf(m, "Speculation_Store_Bypass:\t");
    switch (arch_prctl_spec_ctrl_get(p, PR_SPEC_STORE_BYPASS)) {
    case -EINVAL:
            seq_printf(m, "unknown");
  

-- 2.7.4