x86/amd_node: Fix PCI device reference counting in amd_smn_init()grafted

The local "root" pointer is a temporary variable used during the device
search. Therefore, refcount related to the search iterators should be cleaned
up after the search is complete.

Use the __free() cleanup macro to ensure the refcount is decremented when the
temporary pointer goes out of scope.

Additionally, increment the refcount when caching a root pointer. This ensures
the in-use refcount is separate from the temporary search refcounting.

Finally, drop the redundant "root = NULL" before the second search loop. The
pci_get_class() iterator always decrements the refcount of its "from"
argument, so the first loop can only fall through with "root" already NULL.

Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching")
Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com
Reported-by: Sashiko <sashiko-bot@kernel.org>
Assisted-by: LLM
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Cc: <stable@kernel.org>
Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com

1 files changed, 50 insertions, 0 deletions

diff --git a/include/net/tcp_states.h b/include/net/tcp_states.h
new file mode 100644
index 000000000..d60e8148f
--- /dev/null
+++ b/include/net/tcp_states.h
@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * INET		An implementation of the TCP/IP protocol suite for the LINUX
+ *		operating system.  INET is implemented using the  BSD Socket
+ *		interface as the means of communication with the user level.
+ *
+ *		Definitions for the TCP protocol sk_state field.
+ */
+#ifndef _LINUX_TCP_STATES_H
+#define _LINUX_TCP_STATES_H
+
+enum {
+	TCP_ESTABLISHED = 1,
+	TCP_SYN_SENT,
+	TCP_SYN_RECV,
+	TCP_FIN_WAIT1,
+	TCP_FIN_WAIT2,
+	TCP_TIME_WAIT,
+	TCP_CLOSE,
+	TCP_CLOSE_WAIT,
+	TCP_LAST_ACK,
+	TCP_LISTEN,
+	TCP_CLOSING,	/* Now a valid state */
+	TCP_NEW_SYN_RECV,
+	TCP_BOUND_INACTIVE, /* Pseudo-state for inet_diag */
+
+	TCP_MAX_STATES	/* Leave at the end! */
+};
+
+#define TCP_STATE_MASK	0xF
+
+#define TCP_ACTION_FIN	(1 << TCP_CLOSE)
+
+enum {
+	TCPF_ESTABLISHED = (1 << TCP_ESTABLISHED),
+	TCPF_SYN_SENT	 = (1 << TCP_SYN_SENT),
+	TCPF_SYN_RECV	 = (1 << TCP_SYN_RECV),
+	TCPF_FIN_WAIT1	 = (1 << TCP_FIN_WAIT1),
+	TCPF_FIN_WAIT2	 = (1 << TCP_FIN_WAIT2),
+	TCPF_TIME_WAIT	 = (1 << TCP_TIME_WAIT),
+	TCPF_CLOSE	 = (1 << TCP_CLOSE),
+	TCPF_CLOSE_WAIT	 = (1 << TCP_CLOSE_WAIT),
+	TCPF_LAST_ACK	 = (1 << TCP_LAST_ACK),
+	TCPF_LISTEN	 = (1 << TCP_LISTEN),
+	TCPF_CLOSING	 = (1 << TCP_CLOSING),
+	TCPF_NEW_SYN_RECV = (1 << TCP_NEW_SYN_RECV),
+	TCPF_BOUND_INACTIVE = (1 << TCP_BOUND_INACTIVE),
+};
+
+#endif	/* _LINUX_TCP_STATES_H */