lxc/0035-Seccomp-security-feature-enhanced.patch

From 327e83ff13bec4bf1fa80ede9515d3f9531d7d1f Mon Sep 17 00:00:00 2001
From: wujing <wujing50@huawei.com>
Date: Wed, 15 Apr 2020 06:37:43 -0400
Subject: [PATCH 35/49] Seccomp security feature enhanced

Signed-off-by: wujing <wujing50@huawei.com>
---
 src/lxc/conf.c    |   3 +-
 src/lxc/seccomp.c | 548 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 548 insertions(+), 3 deletions(-)

diff --git a/src/lxc/conf.c b/src/lxc/conf.c
index 6856b1d..e8ee749 100644
--- a/src/lxc/conf.c
+++ b/src/lxc/conf.c
@@ -4730,8 +4730,7 @@ int lxc_setup(struct lxc_handler *handler)
 
 	// isulad: create link /etc/mtab for /proc/mounts
 	if (create_mtab_link() != 0) {
-		ERROR("failed to create link /etc/mtab for target /proc/mounts");
-		goto on_error;
+		return log_error(-1, "failed to create link /etc/mtab for target /proc/mounts");
 	}
 #endif
 
diff --git a/src/lxc/seccomp.c b/src/lxc/seccomp.c
index 081d315..a75adb7 100644
--- a/src/lxc/seccomp.c
+++ b/src/lxc/seccomp.c
@@ -295,7 +295,11 @@ on_error:
 #endif
 
 #if HAVE_DECL_SECCOMP_SYSCALL_RESOLVE_NAME_ARCH
+#ifdef HAVE_ISULAD
+enum lxc_arch_t {
+#else
 enum lxc_hostarch_t {
+#endif
 	lxc_seccomp_arch_all = 0,
 	lxc_seccomp_arch_native,
 	lxc_seccomp_arch_i386,
@@ -351,8 +355,13 @@ int get_hostarch(void)
 	return lxc_seccomp_arch_unknown;
 }
 
+#ifdef HAVE_ISULAD
+scmp_filter_ctx get_new_ctx(enum lxc_arch_t n_arch,
+			    uint32_t default_policy_action, uint32_t *architectures)
+#else
 scmp_filter_ctx get_new_ctx(enum lxc_hostarch_t n_arch,
 			    uint32_t default_policy_action, bool *needs_merge)
+#endif
 {
 	int ret;
 	uint32_t arch;
@@ -475,10 +484,17 @@ scmp_filter_ctx get_new_ctx(enum lxc_hostarch_t n_arch,
 			return NULL;
 		}
 		TRACE("Removed native arch from main seccomp context");
-
+#ifdef HAVE_ISULAD
+		*architectures = arch;
+#else
 		*needs_merge = true;
+#endif
 	} else {
+#ifdef HAVE_ISULAD
+		*architectures = SCMP_ARCH_NATIVE;
+#else
 		*needs_merge = false;
+#endif
 		TRACE("Arch %d already present in main seccomp context", (int)n_arch);
 	}
 
@@ -510,7 +526,11 @@ bool do_resolve_add_rule(uint32_t arch, char *line, scmp_filter_ctx ctx,
 		if (ret < 0) {
 			errno = -ret;
 			SYSERROR("Failed loading rule to reject force umount");
+#ifdef HAVE_ISULAD
+			return true;
+#else
 			return false;
+#endif
 		}
 
 		INFO("Set seccomp rule to reject force umounts");
@@ -519,14 +539,24 @@ bool do_resolve_add_rule(uint32_t arch, char *line, scmp_filter_ctx ctx,
 
 	nr = seccomp_syscall_resolve_name(line);
 	if (nr == __NR_SCMP_ERROR) {
+#ifdef HAVE_ISULAD
+		DEBUG("Failed to resolve syscall \"%s\"", line);
+		DEBUG("This syscall will NOT be handled by seccomp");
+#else
 		WARN("Failed to resolve syscall \"%s\"", line);
 		WARN("This syscall will NOT be handled by seccomp");
+#endif
 		return true;
 	}
 
 	if (nr < 0) {
+#ifdef HAVE_ISULAD
+		DEBUG("Got negative return value %d for syscall \"%s\"", nr, line);
+		DEBUG("This syscall will NOT be handled by seccomp");
+#else
 		WARN("Got negative return value %d for syscall \"%s\"", nr, line);
 		WARN("This syscall will NOT be handled by seccomp");
+#endif
 		return true;
 	}
 
@@ -553,14 +583,42 @@ bool do_resolve_add_rule(uint32_t arch, char *line, scmp_filter_ctx ctx,
 					   rule->args_num, arg_cmp);
 	if (ret < 0) {
 		errno = -ret;
+#ifdef HAVE_ISULAD
+		DEBUG("Failed loading rule for %s (nr %d action %d (%s))",
+		      line, nr, rule->action, get_action_name(rule->action));
+#else
 		SYSERROR("Failed loading rule for %s (nr %d action %d (%s))",
 		         line, nr, rule->action, get_action_name(rule->action));
+#endif
 		return false;
 	}
 
 	return true;
 }
 
+#ifdef HAVE_ISULAD
+#define SCMP_ARCH_INDEX_MAX 3
+
+struct scmp_ctx_info {
+	uint32_t architectures[SCMP_ARCH_INDEX_MAX];
+	enum lxc_arch_t lxc_arch[SCMP_ARCH_INDEX_MAX];
+	scmp_filter_ctx contexts[SCMP_ARCH_INDEX_MAX];
+	bool needs_merge[SCMP_ARCH_INDEX_MAX];
+};
+
+static int get_arch_index(enum lxc_arch_t arch, struct scmp_ctx_info *ctx)
+{
+	int i;
+
+	for (i = 0; i < SCMP_ARCH_INDEX_MAX; i++) {
+		if (ctx->lxc_arch[i] == arch)
+			return i;
+	}
+
+	return -1;
+}
+#endif
+
 /*
  * v2 consists of
  * [x86]
@@ -575,6 +633,493 @@ bool do_resolve_add_rule(uint32_t arch, char *line, scmp_filter_ctx ctx,
  * write
  * close
  */
+#ifdef HAVE_ISULAD
+static int parse_config_v2(FILE *f, char *line, size_t *line_bufsz, struct lxc_conf *conf)
+{
+	int ret;
+	char *p;
+	enum lxc_arch_t cur_rule_arch, native_arch;
+	bool blacklist = false;
+	uint32_t default_policy_action = -1, default_rule_action = -1;
+	struct seccomp_v2_rule rule;
+	struct scmp_ctx_info ctx;
+
+	if (strncmp(line, "blacklist", 9) == 0)
+		blacklist = true;
+	else if (strncmp(line, "whitelist", 9) != 0) {
+		ERROR("Bad seccomp policy style \"%s\"", line);
+		return -1;
+	}
+
+	p = strchr(line, ' ');
+	if (p) {
+		default_policy_action = get_v2_default_action(p + 1);
+		if (default_policy_action == -2)
+			return -1;
+	}
+
+	/* for blacklist, allow any syscall which has no rule */
+	if (blacklist) {
+		if (default_policy_action == -1)
+			default_policy_action = SCMP_ACT_ALLOW;
+
+		if (default_rule_action == -1)
+			default_rule_action = SCMP_ACT_KILL;
+	} else {
+		if (default_policy_action == -1)
+			default_policy_action = SCMP_ACT_KILL;
+
+		if (default_rule_action == -1)
+			default_rule_action = SCMP_ACT_ALLOW;
+	}
+
+	memset(&ctx, 0, sizeof(ctx));
+	ctx.architectures[0] = SCMP_ARCH_NATIVE;
+	ctx.architectures[1] = SCMP_ARCH_NATIVE;
+	ctx.architectures[2] = SCMP_ARCH_NATIVE;
+	native_arch = get_hostarch();
+	cur_rule_arch = native_arch;
+	if (native_arch == lxc_seccomp_arch_amd64) {
+		cur_rule_arch = lxc_seccomp_arch_all;
+
+		ctx.lxc_arch[0] = lxc_seccomp_arch_i386;
+		ctx.contexts[0] = get_new_ctx(lxc_seccomp_arch_i386,
+					      default_policy_action, &ctx.architectures[0]);
+		if (!ctx.contexts[0])
+			goto bad;
+
+		ctx.lxc_arch[1] = lxc_seccomp_arch_x32;
+		ctx.contexts[1] = get_new_ctx(lxc_seccomp_arch_x32,
+					      default_policy_action, &ctx.architectures[1]);
+		if (!ctx.contexts[1])
+			goto bad;
+
+		ctx.lxc_arch[2] = lxc_seccomp_arch_amd64;
+		ctx.contexts[2] = get_new_ctx(lxc_seccomp_arch_amd64,
+					      default_policy_action, &ctx.architectures[2]);
+		if (!ctx.contexts[2])
+			goto bad;
+#ifdef SCMP_ARCH_PPC
+	} else if (native_arch == lxc_seccomp_arch_ppc64) {
+		cur_rule_arch = lxc_seccomp_arch_all;
+
+		ctx.lxc_arch[0] = lxc_seccomp_arch_ppc;
+		ctx.contexts[0] = get_new_ctx(lxc_seccomp_arch_ppc,
+					      default_policy_action, &ctx.architectures[0]);
+		if (!ctx.contexts[0])
+			goto bad;
+
+		ctx.lxc_arch[1] = lxc_seccomp_arch_ppc64;
+		ctx.contexts[1] = get_new_ctx(lxc_seccomp_arch_ppc64,
+					      default_policy_action, &ctx.architectures[1]);
+		if (!ctx.contexts[1])
+			goto bad;
+#endif
+#ifdef SCMP_ARCH_ARM
+	} else if (native_arch == lxc_seccomp_arch_arm64) {
+		cur_rule_arch = lxc_seccomp_arch_all;
+
+		ctx.lxc_arch[0] = lxc_seccomp_arch_arm;
+		ctx.contexts[0] = get_new_ctx(lxc_seccomp_arch_arm,
+					      default_policy_action, &ctx.architectures[0]);
+		if (!ctx.contexts[0])
+			goto bad;
+
+#ifdef SCMP_ARCH_AARCH64
+		ctx.lxc_arch[1] = lxc_seccomp_arch_arm64;
+		ctx.contexts[1] = get_new_ctx(lxc_seccomp_arch_arm64,
+					      default_policy_action, &ctx.architectures[1]);
+		if (!ctx.contexts[1])
+			goto bad;
+#endif
+#endif
+#ifdef SCMP_ARCH_MIPS
+	} else if (native_arch == lxc_seccomp_arch_mips64) {
+		cur_rule_arch = lxc_seccomp_arch_all;
+
+		ctx.lxc_arch[0] = lxc_seccomp_arch_mips;
+		ctx.contexts[0] = get_new_ctx(lxc_seccomp_arch_mips,
+					      default_policy_action, &ctx.architectures[0]);
+		if (!ctx.contexts[0])
+			goto bad;
+
+		ctx.lxc_arch[1] = lxc_seccomp_arch_mips64n32;
+		ctx.contexts[1] = get_new_ctx(lxc_seccomp_arch_mips64n32,
+					      default_policy_action, &ctx.architectures[1]);
+		if (!ctx.contexts[1])
+			goto bad;
+
+		ctx.lxc_arch[2] = lxc_seccomp_arch_mips64;
+		ctx.contexts[2] = get_new_ctx(lxc_seccomp_arch_mips64,
+					      default_policy_action, &ctx.architectures[2]);
+		if (!ctx.contexts[2])
+			goto bad;
+	} else if (native_arch == lxc_seccomp_arch_mipsel64) {
+		cur_rule_arch = lxc_seccomp_arch_all;
+		ctx.lxc_arch[0] = lxc_seccomp_arch_mipsel;
+		ctx.contexts[0] = get_new_ctx(lxc_seccomp_arch_mipsel,
+					      default_policy_action, &ctx.architectures[0]);
+		if (!ctx.contexts[0])
+			goto bad;
+
+		ctx.lxc_arch[1] = lxc_seccomp_arch_mipsel64n32;
+		ctx.contexts[1] = get_new_ctx(lxc_seccomp_arch_mipsel64n32,
+					      default_policy_action, &ctx.architectures[1]);
+		if (!ctx.contexts[1])
+			goto bad;
+
+		ctx.lxc_arch[2] = lxc_seccomp_arch_mipsel64;
+		ctx.contexts[2] = get_new_ctx(lxc_seccomp_arch_mipsel64,
+					      default_policy_action, &ctx.architectures[2]);
+		if (!ctx.contexts[2])
+			goto bad;
+#endif
+	}
+
+	if (default_policy_action != SCMP_ACT_KILL) {
+		ret = seccomp_reset(conf->seccomp.seccomp_ctx, default_policy_action);
+		if (ret != 0) {
+			ERROR("Error re-initializing Seccomp");
+			return -1;
+		}
+
+		ret = seccomp_attr_set(conf->seccomp.seccomp_ctx, SCMP_FLTATR_CTL_NNP, 0);
+		if (ret < 0) {
+			errno = -ret;
+			SYSERROR("Failed to turn off no-new-privs");
+			return -1;
+		}
+
+#ifdef SCMP_FLTATR_ATL_TSKIP
+		ret = seccomp_attr_set(conf->seccomp.seccomp_ctx, SCMP_FLTATR_ATL_TSKIP, 1);
+		if (ret < 0) {
+			errno = -ret;
+			SYSWARN("Failed to turn on seccomp nop-skip, continuing");
+		}
+#endif
+	}
+
+	while (getline(&line, line_bufsz, f) != -1) {
+		if (line[0] == '#')
+			continue;
+
+		if (line[0] == '\0')
+			continue;
+
+		remove_trailing_newlines(line);
+
+		INFO("Processing \"%s\"", line);
+		if (line[0] == '[') {
+			/* Read the architecture for next set of rules. */
+			if (strcmp(line, "[x86]") == 0 ||
+			    strcmp(line, "[X86]") == 0) {
+				if (native_arch != lxc_seccomp_arch_i386 &&
+				    native_arch != lxc_seccomp_arch_amd64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_i386;
+			} else if (strcmp(line, "[x32]") == 0 ||
+				   strcmp(line, "[X32]") == 0) {
+				if (native_arch != lxc_seccomp_arch_amd64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_x32;
+			} else if (strcmp(line, "[X86_64]") == 0 ||
+				   strcmp(line, "[x86_64]") == 0) {
+				if (native_arch != lxc_seccomp_arch_amd64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_amd64;
+			} else if (strcmp(line, "[all]") == 0 ||
+				   strcmp(line, "[ALL]") == 0) {
+				cur_rule_arch = lxc_seccomp_arch_all;
+			}
+#ifdef SCMP_ARCH_ARM
+			else if (strcmp(line, "[arm]") == 0 ||
+				 strcmp(line, "[ARM]") == 0) {
+				if (native_arch != lxc_seccomp_arch_arm &&
+				    native_arch != lxc_seccomp_arch_arm64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_arm;
+			}
+#endif
+#ifdef SCMP_ARCH_AARCH64
+			else if (strcmp(line, "[arm64]") == 0 ||
+				 strcmp(line, "[ARM64]") == 0) {
+				if (native_arch != lxc_seccomp_arch_arm64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_arm64;
+			}
+#endif
+#ifdef SCMP_ARCH_PPC64LE
+			else if (strcmp(line, "[ppc64le]") == 0 ||
+				 strcmp(line, "[PPC64LE]") == 0) {
+				if (native_arch != lxc_seccomp_arch_ppc64le) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_ppc64le;
+			}
+#endif
+#ifdef SCMP_ARCH_PPC64
+			else if (strcmp(line, "[ppc64]") == 0 ||
+				 strcmp(line, "[PPC64]") == 0) {
+				if (native_arch != lxc_seccomp_arch_ppc64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_ppc64;
+			}
+#endif
+#ifdef SCMP_ARCH_PPC
+			else if (strcmp(line, "[ppc]") == 0 ||
+				 strcmp(line, "[PPC]") == 0) {
+				if (native_arch != lxc_seccomp_arch_ppc &&
+				    native_arch != lxc_seccomp_arch_ppc64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_ppc;
+			}
+#endif
+#ifdef SCMP_ARCH_MIPS
+			else if (strcmp(line, "[mips64]") == 0 ||
+				 strcmp(line, "[MIPS64]") == 0) {
+				if (native_arch != lxc_seccomp_arch_mips64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_mips64;
+			} else if (strcmp(line, "[mips64n32]") == 0 ||
+				   strcmp(line, "[MIPS64N32]") == 0) {
+				if (native_arch != lxc_seccomp_arch_mips64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_mips64n32;
+			} else if (strcmp(line, "[mips]") == 0 ||
+				   strcmp(line, "[MIPS]") == 0) {
+				if (native_arch != lxc_seccomp_arch_mips &&
+				    native_arch != lxc_seccomp_arch_mips64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_mips;
+			} else if (strcmp(line, "[mipsel64]") == 0 ||
+				   strcmp(line, "[MIPSEL64]") == 0) {
+				if (native_arch != lxc_seccomp_arch_mipsel64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_mipsel64;
+			} else if (strcmp(line, "[mipsel64n32]") == 0 ||
+				   strcmp(line, "[MIPSEL64N32]") == 0) {
+				if (native_arch != lxc_seccomp_arch_mipsel64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_mipsel64n32;
+			} else if (strcmp(line, "[mipsel]") == 0 ||
+				   strcmp(line, "[MIPSEL]") == 0) {
+				if (native_arch != lxc_seccomp_arch_mipsel &&
+				    native_arch != lxc_seccomp_arch_mipsel64) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_mipsel;
+			}
+#endif
+#ifdef SCMP_ARCH_S390X
+			else if (strcmp(line, "[s390x]") == 0 ||
+				 strcmp(line, "[S390X]") == 0) {
+				if (native_arch != lxc_seccomp_arch_s390x) {
+					cur_rule_arch = lxc_seccomp_arch_unknown;
+					continue;
+				}
+
+				cur_rule_arch = lxc_seccomp_arch_s390x;
+			}
+#endif
+			else {
+				goto bad_arch;
+			}
+
+			continue;
+		}
+
+		/* irrelevant arch - i.e. arm on i386 */
+		if (cur_rule_arch == lxc_seccomp_arch_unknown)
+			continue;
+
+		memset(&rule, 0, sizeof(rule));
+		/* read optional action which follows the syscall */
+		ret = parse_v2_rules(line, default_rule_action, &rule);
+		if (ret != 0) {
+			ERROR("Failed to interpret seccomp rule");
+			goto bad_rule;
+		}
+
+		if (cur_rule_arch == native_arch) {
+			/* add for native arch */
+			if (!do_resolve_add_rule(SCMP_ARCH_NATIVE, line,
+						 conf->seccomp.seccomp_ctx, &rule))
+				goto bad_rule;
+
+			INFO("Added native rule for arch %d for %s action %d(%s)",
+			     SCMP_ARCH_NATIVE, line, rule.action,
+			     get_action_name(rule.action));
+		} else if (cur_rule_arch != lxc_seccomp_arch_all) {
+			/* add for compat specified arch */
+			int arch_index = get_arch_index(cur_rule_arch, &ctx);
+			if (arch_index < 0)
+				goto bad_arch;
+
+			if (!do_resolve_add_rule(ctx.architectures[arch_index], line,
+						 ctx.contexts[arch_index], &rule))
+				goto bad_rule;
+
+			INFO("Added compat rule for arch %d for %s action %d(%s)",
+			     ctx.architectures[arch_index], line, rule.action,
+			     get_action_name(rule.action));
+			ctx.needs_merge[arch_index] = true;
+		} else {
+			/* add for all compat archs */
+			if (!do_resolve_add_rule(SCMP_ARCH_NATIVE, line,
+						 conf->seccomp.seccomp_ctx, &rule))
+				goto bad_rule;
+
+			INFO("Added native rule for arch %d for %s action %d(%s)",
+			     SCMP_ARCH_NATIVE, line, rule.action,
+			     get_action_name(rule.action));
+
+			if (ctx.architectures[0] != SCMP_ARCH_NATIVE) {
+				if (!do_resolve_add_rule(ctx.architectures[0], line,
+							 ctx.contexts[0], &rule))
+					goto bad_rule;
+
+				INFO("Added compat rule for arch %d for %s action %d(%s)",
+				     ctx.architectures[0], line, rule.action,
+				     get_action_name(rule.action));
+				ctx.needs_merge[0] = true;
+			}
+
+			if (ctx.architectures[1] != SCMP_ARCH_NATIVE) {
+				if (!do_resolve_add_rule(ctx.architectures[1], line,
+							 ctx.contexts[1], &rule))
+					goto bad_rule;
+
+				INFO("Added compat rule for arch %d for %s action %d(%s)",
+				     ctx.architectures[1], line, rule.action,
+				     get_action_name(rule.action));
+				ctx.needs_merge[1] = true;
+			}
+
+			if (ctx.architectures[2] != SCMP_ARCH_NATIVE) {
+				if (!do_resolve_add_rule(ctx.architectures[2], line,
+							ctx.contexts[2], &rule))
+					goto bad_rule;
+
+				INFO("Added native rule for arch %d for %s action %d(%s)",
+				     ctx.architectures[2], line, rule.action,
+				     get_action_name(rule.action));
+				ctx.needs_merge[2] = true;
+			}
+		}
+
+	}
+
+	INFO("Merging compat seccomp contexts into main context");
+	if (ctx.contexts[0]) {
+		if (ctx.needs_merge[0]) {
+			ret = seccomp_merge(conf->seccomp.seccomp_ctx, ctx.contexts[0]);
+			if (ret < 0) {
+				ERROR("%s - Failed to merge first compat seccomp "
+				      "context into main context", strerror(-ret));
+				goto bad;
+			}
+
+			TRACE("Merged first compat seccomp context into main context");
+		} else {
+			seccomp_release(ctx.contexts[0]);
+			ctx.contexts[0] = NULL;
+		}
+	}
+
+	if (ctx.contexts[1]) {
+		if (ctx.needs_merge[1]) {
+			ret = seccomp_merge(conf->seccomp.seccomp_ctx, ctx.contexts[1]);
+			if (ret < 0) {
+				ERROR("%s - Failed to merge second compat seccomp "
+				      "context into main context", strerror(-ret));
+				goto bad;
+			}
+
+			TRACE("Merged second compat seccomp context into main context");
+		} else {
+			seccomp_release(ctx.contexts[1]);
+			ctx.contexts[1] = NULL;
+		}
+	}
+
+	if (ctx.contexts[2]) {
+		if (ctx.needs_merge[2]) {
+			ret = seccomp_merge(conf->seccomp.seccomp_ctx, ctx.contexts[2]);
+			if (ret < 0) {
+				ERROR("%s - Failed to merge third compat seccomp "
+				      "context into main context", strerror(-ret));
+				goto bad;
+			}
+
+			TRACE("Merged third compat seccomp context into main context");
+		} else {
+			seccomp_release(ctx.contexts[2]);
+			ctx.contexts[2] = NULL;
+		}
+	}
+
+	free(line);
+	return 0;
+
+bad_arch:
+	ERROR("Unsupported architecture \"%s\"", line);
+
+bad_rule:
+bad:
+	if (ctx.contexts[0])
+		seccomp_release(ctx.contexts[0]);
+
+	if (ctx.contexts[1])
+		seccomp_release(ctx.contexts[1]);
+
+	if (ctx.contexts[2])
+		seccomp_release(ctx.contexts[2]);
+
+	free(line);
+
+	return -1;
+}
+#else
 static int parse_config_v2(FILE *f, char *line, size_t *line_bufsz, struct lxc_conf *conf)
 {
 	int ret;
@@ -1067,6 +1612,7 @@ bad:
 
 	return -1;
 }
+#endif
 #else /* HAVE_DECL_SECCOMP_SYSCALL_RESOLVE_NAME_ARCH */
 static int parse_config_v2(FILE *f, char *line, struct lxc_conf *conf)
 {
-- 
1.8.3.1