From: Christian Ehrhardt <christian.ehrha...@canonical.com> The virtiofsd currently crashes when used with glibc 2.35. That is due to the rseq system call being added to every thread creation [1][2].
[1]: https://www.efficios.com/blog/2019/02/08/linux-restartable-sequences/ [2]: https://sourceware.org/pipermail/libc-alpha/2022-February/136040.html This happens not at daemon start, but when a guest connects /usr/lib/qemu/virtiofsd -f --socket-path=/tmp/testvfsd -o sandbox=chroot \ -o source=/var/guests/j-virtiofs --socket-group=kvm virtio_session_mount: Waiting for vhost-user socket connection... # start ok, now guest will connect virtio_session_mount: Received vhost-user socket connection virtio_loop: Entry fv_queue_set_started: qidx=0 started=1 fv_queue_set_started: qidx=1 started=1 Bad system call (core dumped) We have to put rseq on the seccomp allowlist to avoid that the daemon is crashing in this case. Reported-by: Michael Hudson-Doyle <michael.hud...@canonical.com> Signed-off-by: Christian Ehrhardt <christian.ehrha...@canonical.com> --- tools/virtiofsd/passthrough_seccomp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/tools/virtiofsd/passthrough_seccomp.c b/tools/virtiofsd/passthrough_seccomp.c index a3ce9f898d..21b8f53bd9 100644 --- a/tools/virtiofsd/passthrough_seccomp.c +++ b/tools/virtiofsd/passthrough_seccomp.c @@ -116,6 +116,9 @@ static const int syscall_allowlist[] = { SCMP_SYS(write), SCMP_SYS(writev), SCMP_SYS(umask), +#ifdef __NR_rseq + SCMP_SYS(rseq), /* required since glibc 2.35 */ +#endif }; /* Syscalls used when --syslog is enabled */ -- 2.35.0