Re: [PATCH 05/14] seccomp: recheck the syscall after RET_TRACE
From: Andy Lutomirski <luto@amacapital.net>
Date: 2016-06-09 22:46:36
Also in:
linux-arch, linux-arm-kernel, linux-mips, linux-s390, linux-um, lkml
On Thu, Jun 9, 2016 at 2:01 PM, Kees Cook [off-list ref] wrote:
quoted hunk ↗ jump to hunk
When RET_TRACE triggers, a tracer may change a syscall into something that should be filtered by seccomp. This re-runs seccomp after a trace event to make sure things continue to pass. Signed-off-by: Kees Cook <redacted> Cc: Andy Lutomirski <luto@kernel.org> --- kernel/seccomp.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-)diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 14a37d71b612..54d15eb2b701 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c@@ -556,7 +556,8 @@ void secure_computing_strict(int this_syscall) #else #ifdef CONFIG_SECCOMP_FILTER -static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd) +static int __seccomp_filter(int this_syscall, const struct seccomp_data *sd, + const bool recheck_after_trace)
This patch looks good with one minor nit: I read this as "pass true if you want to recheck after trace", which is exactly the opposite of how it works. --Andy