kbuild: rust: keep Rust objects out of Clang LTO with inline helpersgrafted

Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit
`objtool` errors such as:

    vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a:
    can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd

The reason is that in such builds, the Clang invocation that compiles
the combined Rust plus helpers bitcode emits LLVM bitcode (again) --
the final code generation happens in the linker's LTO step, which the
`-mllvm` trap options passed to Clang do not reach.

This, in turn, means that unreachable traps are missing, and the
impossible paths do not merely fallthrough to the next symbol, but past
the end of their own section, since LTO builds place each function in
its own section.

Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always
emits machine code directly, with the traps in place.

Assisted-by: LLM
Cc: Gary Guo <gary@garyguo.net>
Cc: Boqun Feng <boqun@kernel.org>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Matthew Maurer <mmaurer@google.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust")
Acked-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

1 files changed, 193 insertions, 0 deletions

diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h
new file mode 100644
index 000000000..90cb61b16
--- /dev/null
+++ b/security/selinux/include/classmap.h
@@ -0,0 +1,193 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#define COMMON_FILE_SOCK_PERMS                                            \
+	"ioctl", "read", "write", "create", "getattr", "setattr", "lock", \
+		"relabelfrom", "relabelto", "append", "map"
+
+#define COMMON_FILE_PERMS                                                \
+	COMMON_FILE_SOCK_PERMS, "unlink", "link", "rename", "execute",   \
+		"quotaon", "mounton", "audit_access", "open", "execmod", \
+		"watch", "watch_mount", "watch_sb", "watch_with_perm",   \
+		"watch_reads", "watch_mountns"
+
+#define COMMON_SOCK_PERMS                                              \
+	COMMON_FILE_SOCK_PERMS, "bind", "connect", "listen", "accept", \
+		"getopt", "setopt", "shutdown", "recvfrom", "sendto",  \
+		"name_bind"
+
+#define COMMON_IPC_PERMS                                            \
+	"create", "destroy", "getattr", "setattr", "read", "write", \
+		"associate", "unix_read", "unix_write"
+
+#define COMMON_CAP_PERMS                                                     \
+	"chown", "dac_override", "dac_read_search", "fowner", "fsetid",      \
+		"kill", "setgid", "setuid", "setpcap", "linux_immutable",    \
+		"net_bind_service", "net_broadcast", "net_admin", "net_raw", \
+		"ipc_lock", "ipc_owner", "sys_module", "sys_rawio",          \
+		"sys_chroot", "sys_ptrace", "sys_pacct", "sys_admin",        \
+		"sys_boot", "sys_nice", "sys_resource", "sys_time",          \
+		"sys_tty_config", "mknod", "lease", "audit_write",           \
+		"audit_control", "setfcap"
+
+#define COMMON_CAP2_PERMS                                                     \
+	"mac_override", "mac_admin", "syslog", "wake_alarm", "block_suspend", \
+		"audit_read", "perfmon", "bpf", "checkpoint_restore"
+
+#ifdef __KERNEL__ /* avoid this check when building host programs */
+#include <linux/capability.h>
+
+#if CAP_LAST_CAP > CAP_CHECKPOINT_RESTORE
+#error New capability defined, please update COMMON_CAP2_PERMS.
+#endif
+#endif
+
+/*
+ * Note: The name for any socket class should be suffixed by "socket",
+ *	 and doesn't contain more than one substr of "socket".
+ */
+const struct security_class_mapping secclass_map[] = {
+	{ "security",
+	  { "compute_av", "compute_create", "compute_member", "check_context",
+	    "load_policy", "compute_relabel", "compute_user", "setenforce",
+	    "setbool", "setsecparam", "setcheckreqprot", "read_policy",
+	    "validate_trans", NULL } },
+	{ "process",
+	  { "fork",	    "transition",    "sigchld",	    "sigkill",
+	    "sigstop",	    "signull",	     "signal",	    "ptrace",
+	    "getsched",	    "setsched",	     "getsession",  "getpgid",
+	    "setpgid",	    "getcap",	     "setcap",	    "share",
+	    "getattr",	    "setexec",	     "setfscreate", "noatsecure",
+	    "siginh",	    "setrlimit",     "rlimitinh",   "dyntransition",
+	    "setcurrent",   "execmem",	     "execstack",   "execheap",
+	    "setkeycreate", "setsockcreate", "getrlimit",   NULL } },
+	{ "process2", { "nnp_transition", "nosuid_transition", NULL } },
+	{ "system",
+	  { "ipc_info", "syslog_read", "syslog_mod", "syslog_console",
+	    "module_request", "module_load", "firmware_load",
+	    "kexec_image_load", "kexec_initramfs_load", "policy_load",
+	    "x509_certificate_load", NULL } },
+	{ "capability", { COMMON_CAP_PERMS, NULL } },
+	{ "filesystem",
+	  { "mount", "remount", "unmount", "getattr", "relabelfrom",
+	    "relabelto", "associate", "quotamod", "quotaget", "watch", NULL } },
+	{ "file",
+	  { COMMON_FILE_PERMS, "execute_no_trans", "entrypoint", NULL } },
+	{ "dir",
+	  { COMMON_FILE_PERMS, "add_name", "remove_name", "reparent", "search",
+	    "rmdir", NULL } },
+	{ "fd", { "use", NULL } },
+	{ "lnk_file", { COMMON_FILE_PERMS, NULL } },
+	{ "chr_file", { COMMON_FILE_PERMS, NULL } },
+	{ "blk_file", { COMMON_FILE_PERMS, NULL } },
+	{ "sock_file", { COMMON_FILE_PERMS, NULL } },
+	{ "fifo_file", { COMMON_FILE_PERMS, NULL } },
+	{ "socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "tcp_socket",
+	  { COMMON_SOCK_PERMS, "node_bind", "name_connect", NULL } },
+	{ "udp_socket", { COMMON_SOCK_PERMS, "node_bind", NULL } },
+	{ "rawip_socket", { COMMON_SOCK_PERMS, "node_bind", NULL } },
+	{ "node", { "recvfrom", "sendto", NULL } },
+	{ "netif", { "ingress", "egress", NULL } },
+	{ "netlink_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "packet_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "key_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "unix_stream_socket", { COMMON_SOCK_PERMS, "connectto", NULL } },
+	{ "unix_dgram_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "sem", { COMMON_IPC_PERMS, NULL } },
+	{ "msg", { "send", "receive", NULL } },
+	{ "msgq", { COMMON_IPC_PERMS, "enqueue", NULL } },
+	{ "shm", { COMMON_IPC_PERMS, "lock", NULL } },
+	{ "ipc", { COMMON_IPC_PERMS, NULL } },
+	{ "netlink_route_socket",
+	  { COMMON_SOCK_PERMS, "nlmsg_read", "nlmsg_write", "nlmsg", NULL } },
+	{ "netlink_tcpdiag_socket",
+	  { COMMON_SOCK_PERMS, "nlmsg_read", "nlmsg_write", "nlmsg", NULL } },
+	{ "netlink_nflog_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "netlink_xfrm_socket",
+	  { COMMON_SOCK_PERMS, "nlmsg_read", "nlmsg_write", "nlmsg", NULL } },
+	{ "netlink_selinux_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "netlink_iscsi_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "netlink_audit_socket",
+	  { COMMON_SOCK_PERMS, "nlmsg_read", "nlmsg_write", "nlmsg_relay",
+	    "nlmsg_readpriv", "nlmsg_tty_audit", "nlmsg", NULL } },
+	{ "netlink_fib_lookup_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "netlink_connector_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "netlink_netfilter_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "netlink_dnrt_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "association",
+	  { "sendto", "recvfrom", "setcontext", "polmatch", NULL } },
+	{ "netlink_kobject_uevent_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "netlink_generic_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "netlink_scsitransport_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "netlink_rdma_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "netlink_crypto_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "appletalk_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "packet",
+	  { "send", "recv", "relabelto", "forward_in", "forward_out", NULL } },
+	{ "key",
+	  { "view", "read", "write", "search", "link", "setattr", "create",
+	    NULL } },
+	{ "memprotect", { "mmap_zero", NULL } },
+	{ "peer", { "recv", NULL } },
+	{ "capability2", { COMMON_CAP2_PERMS, NULL } },
+	{ "kernel_service", { "use_as_override", "create_files_as", NULL } },
+	{ "tun_socket", { COMMON_SOCK_PERMS, "attach_queue", NULL } },
+	{ "binder",
+	  { "impersonate", "call", "set_context_mgr", "transfer", NULL } },
+	{ "cap_userns", { COMMON_CAP_PERMS, NULL } },
+	{ "cap2_userns", { COMMON_CAP2_PERMS, NULL } },
+	{ "sctp_socket",
+	  { COMMON_SOCK_PERMS, "node_bind", "name_connect", "association",
+	    NULL } },
+	{ "icmp_socket", { COMMON_SOCK_PERMS, "node_bind", NULL } },
+	{ "ax25_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "ipx_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "netrom_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "atmpvc_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "x25_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "rose_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "decnet_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "atmsvc_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "rds_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "irda_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "pppox_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "llc_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "can_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "tipc_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "bluetooth_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "iucv_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "rxrpc_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "isdn_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "phonet_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "ieee802154_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "caif_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "alg_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "nfc_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "vsock_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "kcm_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "qipcrtr_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "smc_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "infiniband_pkey", { "access", NULL } },
+	{ "infiniband_endport", { "manage_subnet", NULL } },
+	{ "bpf",
+	  { "map_create", "map_read", "map_write", "prog_load", "prog_run",
+	    "map_create_as", "prog_load_as", NULL } },
+	{ "xdp_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "mctp_socket", { COMMON_SOCK_PERMS, NULL } },
+	{ "perf_event",
+	  { "open", "cpu", "kernel", "tracepoint", "read", "write", NULL } },
+	{ "anon_inode", { COMMON_FILE_PERMS, NULL } },
+	{ "io_uring", { "override_creds", "sqpoll", "cmd", "allowed", NULL } },
+	{ "user_namespace", { "create", NULL } },
+	{ "memfd_file",
+	  { COMMON_FILE_PERMS, "execute_no_trans", "entrypoint", NULL } },
+	/* last one */ { NULL, {} }
+};
+
+#ifdef __KERNEL__ /* avoid this check when building host programs */
+#include <linux/socket.h>
+
+#if PF_MAX > 46
+#error New address family defined, please update secclass_map.
+#endif
+#endif