From c818c03b661cd769e035e41673d5543ba2ebda64 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 13 May 2020 14:11:26 -0700 Subject: seccomp: Report number of loaded filters in /proc/$pid/status A common question asked when debugging seccomp filters is "how many filters are attached to your process?" Provide a way to easily answer this question through /proc/$pid/status with a "Seccomp_filters" line. Signed-off-by: Kees Cook --- kernel/seccomp.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'kernel/seccomp.c') diff --git a/kernel/seccomp.c b/kernel/seccomp.c index d653d8426de9..f387e5004c29 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -398,6 +398,8 @@ static inline void seccomp_sync_threads(unsigned long flags) put_seccomp_filter(thread); smp_store_release(&thread->seccomp.filter, caller->seccomp.filter); + atomic_set(&thread->seccomp.filter_count, + atomic_read(&thread->seccomp.filter_count)); /* * Don't let an unprivileged task work around @@ -544,6 +546,7 @@ static long seccomp_attach_filter(unsigned int flags, */ filter->prev = current->seccomp.filter; current->seccomp.filter = filter; + atomic_inc(¤t->seccomp.filter_count); /* Now that the new filter is in place, synchronize to all threads. */ if (flags & SECCOMP_FILTER_FLAG_TSYNC) -- cgit