objtool: Validate disassembler headers in libopcodes probegrafted

commit 3f2de814c059 ("objtool: Fix libopcodes linking with static libraries")
tested for libopcodes availability by linking a test snippet with a forward
declaration of disassemble_init_for_target().

However, testing symbol linkage with an extern declaration only verifies
the presence of the library (.so/.a) and bypasses checking for development
headers (binutils-dev). On systems where libopcodes is present without
development headers installed, the probe succeeds, enabling BUILD_DISAS.
Subsequent compilation of objtool then fails:

  fatal error: 'bfd.h' file not found
    113 | #include <bfd.h>

Additionally, the probe invokes $(HOSTCC) without $(HOSTCFLAGS), ignoring
any sysroot or include flags specified for the host compiler.

Fix this by including <bfd.h> and <dis-asm.h> directly in the test snippet,
passing $(HOSTCFLAGS) so host compiler options are respected, and defining
PACKAGE="objtool" to satisfy the configuration check in <bfd.h>.

Fixes: 3f2de814c059 ("objtool: Fix libopcodes linking with static libraries")
Fixes: 436326bc525d ("objtool: fix build failure due to missing libopcodes check")
Reported-by: Alice Ryhl <aliceryhl@google.com>
Assisted-by: Antigravity:Gemini-Next
Signed-off-by: Ulises Mendez Martinez <umendez@google.com>
Link: https://patch.msgid.link/20260904150710.2997558-1-umendez@google.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>

1 files changed, 133 insertions, 0 deletions

diff --git a/include/net/phonet/phonet.h b/include/net/phonet/phonet.h
new file mode 100644
index 000000000..cf5ecae4a
--- /dev/null
+++ b/include/net/phonet/phonet.h
@@ -0,0 +1,133 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * File: af_phonet.h
+ *
+ * Phonet sockets kernel definitions
+ *
+ * Copyright (C) 2008 Nokia Corporation.
+ */
+
+#ifndef AF_PHONET_H
+#define AF_PHONET_H
+
+#include <linux/phonet.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+
+/*
+ * The lower layers may not require more space, ever. Make sure it's
+ * enough.
+ */
+#define MAX_PHONET_HEADER	(8 + MAX_HEADER)
+
+/*
+ * Every Phonet* socket has this structure first in its
+ * protocol-specific structure under name c.
+ */
+struct pn_sock {
+	struct sock	sk;
+	u16		sobject;
+	u16		dobject;
+	u8		resource;
+};
+
+static inline struct pn_sock *pn_sk(struct sock *sk)
+{
+	return (struct pn_sock *)sk;
+}
+
+extern const struct proto_ops phonet_dgram_ops;
+
+void pn_sock_init(void);
+struct sock *pn_find_sock_by_sa(struct net *net, const struct sockaddr_pn *sa);
+void pn_deliver_sock_broadcast(struct net *net, struct sk_buff *skb);
+void phonet_get_local_port_range(int *min, int *max);
+int pn_sock_hash(struct sock *sk);
+void pn_sock_unhash(struct sock *sk);
+int pn_sock_get_port(struct sock *sk, unsigned short sport);
+
+struct sock *pn_find_sock_by_res(struct net *net, u8 res);
+int pn_sock_bind_res(struct sock *sock, u8 res);
+int pn_sock_unbind_res(struct sock *sk, u8 res);
+void pn_sock_unbind_all_res(struct sock *sk);
+
+int pn_skb_send(struct sock *sk, struct sk_buff *skb,
+		const struct sockaddr_pn *target);
+
+static inline struct phonethdr *pn_hdr(struct sk_buff *skb)
+{
+	return (struct phonethdr *)skb_network_header(skb);
+}
+
+static inline struct phonetmsg *pn_msg(struct sk_buff *skb)
+{
+	return (struct phonetmsg *)skb_transport_header(skb);
+}
+
+/*
+ * Get the other party's sockaddr from received skb. The skb begins
+ * with a Phonet header.
+ */
+static inline
+void pn_skb_get_src_sockaddr(struct sk_buff *skb, struct sockaddr_pn *sa)
+{
+	struct phonethdr *ph = pn_hdr(skb);
+	u16 obj = pn_object(ph->pn_sdev, ph->pn_sobj);
+
+	sa->spn_family = AF_PHONET;
+	pn_sockaddr_set_object(sa, obj);
+	pn_sockaddr_set_resource(sa, ph->pn_res);
+	memset(sa->spn_zero, 0, sizeof(sa->spn_zero));
+}
+
+static inline
+void pn_skb_get_dst_sockaddr(struct sk_buff *skb, struct sockaddr_pn *sa)
+{
+	struct phonethdr *ph = pn_hdr(skb);
+	u16 obj = pn_object(ph->pn_rdev, ph->pn_robj);
+
+	sa->spn_family = AF_PHONET;
+	pn_sockaddr_set_object(sa, obj);
+	pn_sockaddr_set_resource(sa, ph->pn_res);
+	memset(sa->spn_zero, 0, sizeof(sa->spn_zero));
+}
+
+/* Protocols in Phonet protocol family. */
+struct phonet_protocol {
+	const struct proto_ops	*ops;
+	struct proto		*prot;
+	int			sock_type;
+};
+
+int phonet_proto_register(unsigned int protocol,
+		const struct phonet_protocol *pp);
+void phonet_proto_unregister(unsigned int protocol,
+		const struct phonet_protocol *pp);
+
+int phonet_sysctl_init(void);
+void phonet_sysctl_exit(void);
+int isi_register(void);
+void isi_unregister(void);
+
+static inline bool sk_is_phonet(struct sock *sk)
+{
+	return sk->sk_family == PF_PHONET;
+}
+
+static inline int phonet_sk_ioctl(struct sock *sk, unsigned int cmd,
+				  void __user *arg)
+{
+	int karg;
+
+	switch (cmd) {
+	case SIOCPNADDRESOURCE:
+	case SIOCPNDELRESOURCE:
+		if (get_user(karg, (int __user *)arg))
+			return -EFAULT;
+
+		return sk->sk_prot->ioctl(sk, cmd, &karg);
+	}
+	/* A positive return value means that the ioctl was not processed */
+	return 1;
+}
+#endif