From 3036bedf30d413e8236ec962b9c91b66988c2204 Mon Sep 17 00:00:00 2001 From: Micah Elizabeth Scott Date: Tue, 30 May 2023 09:53:09 -0700 Subject: Update CI builds to Debian Bullseye, fix associated compatibility bugs This is a change intended for 0.4.7 maintenance as well as main. The CI builds use Debian Buster which is now end of life, and I was experiencing inconsistent CI failures with accessing its security update server. I wanted to update CI to a distro that isn't EOL, and Bullseye is the current stable release of Debian. This opened up a small can of worms that this commit also deals with. In particular there's a docker engine bug that we work around by removing the docker-specific apt cleanup script if it exists, and there's a new incompatibility between tracing and sandbox support. The tracing/sandbox incompatibility itself had two parts: - The membarrier() syscall is used to deliver inter-processor synchronization events, and the external "userspace-rcu" data structure library would make assumptions that if membarrier is available at initialization it always will be. This caused segfaults in some cases when running trace + sandbox. Resolved this by allowing membarrier entirely, in the sandbox. - userspace-rcu also assumes it can block signals, and fails hard if this can't be done. We already include a similar carveout to allow this in the sandbox for fragile-hardening, so I extended that to cover tracing as well. Addresses issue #40799 Signed-off-by: Micah Elizabeth Scott --- src/lib/sandbox/sandbox.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'src') diff --git a/src/lib/sandbox/sandbox.c b/src/lib/sandbox/sandbox.c index 6800fa062b..5dace3a8a2 100644 --- a/src/lib/sandbox/sandbox.c +++ b/src/lib/sandbox/sandbox.c @@ -220,6 +220,10 @@ static int filter_nopar_gen[] = { #endif // glob uses this.. SCMP_SYS(lstat), +#ifdef __NR_membarrier + /* Inter-processor synchronization, needed for tracing support */ + SCMP_SYS(membarrier), +#endif SCMP_SYS(mkdir), SCMP_SYS(mlockall), #ifdef __NR_mmap @@ -1165,7 +1169,8 @@ sb_rt_sigprocmask(scmp_filter_ctx ctx, sandbox_cfg_t *filter) int rc = 0; (void) filter; -#ifdef ENABLE_FRAGILE_HARDENING +#if defined(ENABLE_FRAGILE_HARDENING) || \ + defined(USE_TRACING_INSTRUMENTATION_LTTNG) rc = seccomp_rule_add_1(ctx, SCMP_ACT_ALLOW, SCMP_SYS(rt_sigprocmask), SCMP_CMP(0, SCMP_CMP_EQ, SIG_BLOCK)); if (rc) -- cgit v1.2.3-54-g00ecf