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, 79 insertions, 0 deletions

diff --git a/fs/hfsplus/xattr_security.c b/fs/hfsplus/xattr_security.c
new file mode 100644
index 000000000..90f68ec11
--- /dev/null
+++ b/fs/hfsplus/xattr_security.c
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/hfsplus/xattr_trusted.c
+ *
+ * Vyacheslav Dubeyko <slava@dubeyko.com>
+ *
+ * Handler for storing security labels as extended attributes.
+ */
+
+#include <linux/security.h>
+#include <linux/nls.h>
+
+#include "hfsplus_fs.h"
+#include "xattr.h"
+
+static int hfsplus_security_getxattr(const struct xattr_handler *handler,
+				     struct dentry *unused, struct inode *inode,
+				     const char *name, void *buffer, size_t size)
+{
+	return hfsplus_getxattr(inode, name, buffer, size,
+				XATTR_SECURITY_PREFIX,
+				XATTR_SECURITY_PREFIX_LEN);
+}
+
+static int hfsplus_security_setxattr(const struct xattr_handler *handler,
+				     struct mnt_idmap *idmap,
+				     struct dentry *unused, struct inode *inode,
+				     const char *name, const void *buffer,
+				     size_t size, int flags)
+{
+	return hfsplus_setxattr(inode, name, buffer, size, flags,
+				XATTR_SECURITY_PREFIX,
+				XATTR_SECURITY_PREFIX_LEN);
+}
+
+static int hfsplus_initxattrs(struct inode *inode,
+				const struct xattr *xattr_array,
+				void *fs_info)
+{
+	const struct xattr *xattr;
+	char *xattr_name;
+	int err = 0;
+
+	xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN + 1,
+		GFP_KERNEL);
+	if (!xattr_name)
+		return -ENOMEM;
+	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+
+		if (!strcmp(xattr->name, ""))
+			continue;
+
+		strcpy(xattr_name, XATTR_SECURITY_PREFIX);
+		strcpy(xattr_name +
+			XATTR_SECURITY_PREFIX_LEN, xattr->name);
+		memset(xattr_name +
+			XATTR_SECURITY_PREFIX_LEN + strlen(xattr->name), 0, 1);
+
+		err = __hfsplus_setxattr(inode, xattr_name,
+					xattr->value, xattr->value_len, 0);
+		if (err)
+			break;
+	}
+	kfree(xattr_name);
+	return err;
+}
+
+int hfsplus_init_security(struct inode *inode, struct inode *dir,
+				const struct qstr *qstr)
+{
+	return security_inode_init_security(inode, dir, qstr,
+					&hfsplus_initxattrs, NULL);
+}
+
+const struct xattr_handler hfsplus_xattr_security_handler = {
+	.prefix	= XATTR_SECURITY_PREFIX,
+	.get	= hfsplus_security_getxattr,
+	.set	= hfsplus_security_setxattr,
+};