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, 68 insertions, 0 deletions

diff --git a/include/net/sctp/ulpqueue.h b/include/net/sctp/ulpqueue.h
new file mode 100644
index 000000000..60f664129
--- /dev/null
+++ b/include/net/sctp/ulpqueue.h
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* SCTP kernel implementation
+ * (C) Copyright IBM Corp. 2001, 2004
+ * Copyright (c) 1999-2000 Cisco, Inc.
+ * Copyright (c) 1999-2001 Motorola, Inc.
+ * Copyright (c) 2001 Intel Corp.
+ * Copyright (c) 2001 Nokia, Inc.
+ * Copyright (c) 2001 La Monte H.P. Yarroll
+ *
+ * These are the definitions needed for the sctp_ulpq type.  The
+ * sctp_ulpq is the interface between the Upper Layer Protocol, or ULP,
+ * and the core SCTP state machine.  This is the component which handles
+ * reassembly and ordering.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email addresses:
+ *    lksctp developers <linux-sctp@vger.kernel.org>
+ *
+ * Written or modified by:
+ *   Jon Grimm             <jgrimm@us.ibm.com>
+ *   La Monte H.P. Yarroll <piggy@acm.org>
+ *   Sridhar Samudrala     <sri@us.ibm.com>
+ */
+
+#ifndef __sctp_ulpqueue_h__
+#define __sctp_ulpqueue_h__
+
+/* A structure to carry information to the ULP (e.g. Sockets API) */
+struct sctp_ulpq {
+	char pd_mode;
+	struct sctp_association *asoc;
+	struct sk_buff_head reasm;
+	struct sk_buff_head reasm_uo;
+	struct sk_buff_head lobby;
+};
+
+/* Prototypes. */
+void sctp_ulpq_init(struct sctp_ulpq *ulpq, struct sctp_association *asoc);
+void sctp_ulpq_flush(struct sctp_ulpq *ulpq);
+void sctp_ulpq_free(struct sctp_ulpq *);
+
+/* Add a new DATA chunk for processing. */
+int sctp_ulpq_tail_data(struct sctp_ulpq *, struct sctp_chunk *, gfp_t);
+
+/* Add a new event for propagation to the ULP. */
+int sctp_ulpq_tail_event(struct sctp_ulpq *, struct sk_buff_head *skb_list);
+
+/* Renege previously received chunks.  */
+void sctp_ulpq_renege(struct sctp_ulpq *, struct sctp_chunk *, gfp_t);
+
+/* Perform partial delivery. */
+void sctp_ulpq_partial_delivery(struct sctp_ulpq *, gfp_t);
+
+/* Abort the partial delivery. */
+void sctp_ulpq_abort_pd(struct sctp_ulpq *, gfp_t);
+
+/* Clear the partial data delivery condition on this socket. */
+int sctp_clear_pd(struct sock *sk, struct sctp_association *asoc);
+
+/* Skip over an SSN. */
+void sctp_ulpq_skip(struct sctp_ulpq *ulpq, __u16 sid, __u16 ssn);
+
+void sctp_ulpq_reasm_flushtsn(struct sctp_ulpq *, __u32);
+
+__u16 sctp_ulpq_renege_list(struct sctp_ulpq *ulpq,
+			    struct sk_buff_head *list, __u16 needed);
+
+#endif /* __sctp_ulpqueue_h__ */