From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tycho Andersen Subject: Re: [PATCH v2 1/2] samples, selftests/seccomp: Zero out seccomp_notif Date: Sat, 28 Dec 2019 11:18:25 -0700 Message-ID: <20191228181825.GB6746@cisco> References: <20191228014837.GA31774@ircssh-2.c.rugged-nimbus-611.internal> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20191228014837.GA31774@ircssh-2.c.rugged-nimbus-611.internal> Sender: linux-kernel-owner@vger.kernel.org To: Sargun Dhillon Cc: linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, jannh@google.com, christian.brauner@ubuntu.com, keescook@chromium.org, cyphar@cyphar.com List-Id: linux-api@vger.kernel.org On Sat, Dec 28, 2019 at 01:48:39AM +0000, Sargun Dhillon wrote: > The seccomp_notif structure should be zeroed out prior to calling the > SECCOMP_IOCTL_NOTIF_RECV ioctl. Previously, the kernel did not check > whether these structures were zeroed out or not, so these worked. > > Signed-off-by: Sargun Dhillon > Cc: Kees Cook > --- > samples/seccomp/user-trap.c | 2 +- > tools/testing/selftests/seccomp/seccomp_bpf.c | 2 ++ > 2 files changed, 3 insertions(+), 1 deletion(-) > > diff --git a/samples/seccomp/user-trap.c b/samples/seccomp/user-trap.c > index 6d0125ca8af7..0ca8fb37cd79 100644 > --- a/samples/seccomp/user-trap.c > +++ b/samples/seccomp/user-trap.c > @@ -298,7 +298,6 @@ int main(void) > req = malloc(sizes.seccomp_notif); > if (!req) > goto out_close; > - memset(req, 0, sizeof(*req)); > > resp = malloc(sizes.seccomp_notif_resp); > if (!resp) > @@ -306,6 +305,7 @@ int main(void) > memset(resp, 0, sizeof(*resp)); I know it's unrelated, but it's probably worth sending a patch to fix this to be sizes.seccomp_notif_resp instead of sizeof(*resp), since if the kernel is older this will over-zero things. I can do that, or you can add the patch to this series, just let me know which. But in any case, this patch is: Reviewed-by: Tycho Andersen Cheers, Tycho