commit 8bb8f15a7d049ed26c69d95087065b381f76ec4d
Author: Michael Hudson-Doyle <michael.hudson@canonical.com>
Date:   Wed Feb 9 09:06:13 2022 +0100

    sys_linux: allow rseq in seccomp filter
    
    Libc 2.35 will use rseq syscalls [1][2] by default and thereby
    break chrony in seccomp isolation.
    
    [1]: https://www.efficios.com/blog/2019/02/08/linux-restartable-sequences/
    [2]: https://sourceware.org/pipermail/libc-alpha/2022-February/136040.html
    
    Tested-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
    Reviewed-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
    Signed-off-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
    Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>

diff --git a/sys_linux.c b/sys_linux.c
index 9cab2efa..cc3c9311 100644
--- a/sys_linux.c
+++ b/sys_linux.c
@@ -497,6 +497,9 @@ SYS_Linux_EnableSystemCallFilter(int level, SYS_ProcessContext context)
     SCMP_SYS(getrlimit),
     SCMP_SYS(getuid),
     SCMP_SYS(getuid32),
+#ifdef __NR_rseq
+    SCMP_SYS(rseq),
+#endif
     SCMP_SYS(rt_sigaction),
     SCMP_SYS(rt_sigreturn),
     SCMP_SYS(rt_sigprocmask),