selftests/bpf: Test packet range of pointers sharing an idgrafted

Add tests where two packet pointers share an id and tightening one
pointer's umax from its var_off would put it less than their constant
distance from the other's umax: with an index & 0x38 capped at 50, the
base pointer keeps umax 50, so the pointer 8 bytes further on must keep
umax 58, even though its known bits allow at most 56.

These refused a valid program or accepted an out-of-bounds access before
the fix:

- check the advanced copy, load through the base: valid, was refused;
- check the base, load the byte at base + 1 through a copy advanced by
  8: was accepted;
- check base + 4, load 4 bytes at base + 2 through base + 8: reads two
  bytes past the checked range, was accepted;
- the same as the second with data_meta pointers checked against data:
  was accepted.

These pass with and without the fix and cover nearby paths:

- subtract an unknown scalar from a checked pointer and load below it
  (the range is kept across a new id);
- reach a load through two paths whose checks cover 8 and 7 bytes after
  the loaded pointer; the second path must not be pruned by the first;
- spill a copy of a pointer, check the pointer, fill the copy and load
  one byte past the checked range: the load is refused, and the copy
  has the range of the check.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

1 files changed, 205 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/dsdebug.c b/drivers/acpi/acpica/dsdebug.c
new file mode 100644
index 000000000..691c00159
--- /dev/null
+++ b/drivers/acpi/acpica/dsdebug.c
@@ -0,0 +1,205 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/******************************************************************************
+ *
+ * Module Name: dsdebug - Parser/Interpreter interface - debugging
+ *
+ * Copyright (C) 2000 - 2026, Intel Corp.
+ *
+ *****************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acdispat.h"
+#include "acnamesp.h"
+#ifdef ACPI_DISASSEMBLER
+#include "acdisasm.h"
+#endif
+#include "acinterp.h"
+
+#define _COMPONENT          ACPI_DISPATCHER
+ACPI_MODULE_NAME("dsdebug")
+
+#if defined(ACPI_DEBUG_OUTPUT) || defined(ACPI_DEBUGGER)
+/* Local prototypes */
+static void
+acpi_ds_print_node_pathname(struct acpi_namespace_node *node,
+			    const char *message);
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_print_node_pathname
+ *
+ * PARAMETERS:  node            - Object
+ *              message         - Prefix message
+ *
+ * DESCRIPTION: Print an object's full namespace pathname
+ *              Manages allocation/freeing of a pathname buffer
+ *
+ ******************************************************************************/
+
+static void
+acpi_ds_print_node_pathname(struct acpi_namespace_node *node,
+			    const char *message)
+{
+	struct acpi_buffer buffer;
+	acpi_status status;
+
+	ACPI_FUNCTION_TRACE(ds_print_node_pathname);
+
+	if (!node) {
+		ACPI_DEBUG_PRINT_RAW((ACPI_DB_DISPATCH, "[NULL NAME]"));
+		return_VOID;
+	}
+
+	/* Convert handle to full pathname and print it (with supplied message) */
+
+	buffer.length = ACPI_ALLOCATE_LOCAL_BUFFER;
+
+	status = acpi_ns_handle_to_pathname(node, &buffer, TRUE);
+	if (ACPI_SUCCESS(status)) {
+		if (message) {
+			ACPI_DEBUG_PRINT_RAW((ACPI_DB_DISPATCH, "%s ",
+					      message));
+		}
+
+		ACPI_DEBUG_PRINT_RAW((ACPI_DB_DISPATCH, "[%s] (Node %p)",
+				      (char *)buffer.pointer, node));
+		ACPI_FREE(buffer.pointer);
+	}
+
+	return_VOID;
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ds_dump_method_stack
+ *
+ * PARAMETERS:  status          - Method execution status
+ *              walk_state      - Current state of the parse tree walk
+ *              op              - Executing parse op
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Called when a method has been aborted because of an error.
+ *              Dumps the method execution stack.
+ *
+ ******************************************************************************/
+
+void
+acpi_ds_dump_method_stack(acpi_status status,
+			  struct acpi_walk_state *walk_state,
+			  union acpi_parse_object *op)
+{
+	union acpi_parse_object *next;
+	struct acpi_thread_state *thread;
+	struct acpi_walk_state *next_walk_state;
+	struct acpi_namespace_node *previous_method = NULL;
+	union acpi_operand_object *method_desc;
+
+	ACPI_FUNCTION_TRACE(ds_dump_method_stack);
+
+	/* Ignore control codes, they are not errors */
+
+	if (ACPI_CNTL_EXCEPTION(status)) {
+		return_VOID;
+	}
+
+	/* We may be executing a deferred opcode */
+
+	if (walk_state->deferred_node) {
+		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+				  "Executing subtree for Buffer/Package/Region\n"));
+		return_VOID;
+	}
+
+	/*
+	 * If there is no Thread, we are not actually executing a method.
+	 * This can happen when the iASL compiler calls the interpreter
+	 * to perform constant folding.
+	 */
+	thread = walk_state->thread;
+	if (!thread) {
+		return_VOID;
+	}
+
+	/* Display exception and method name */
+
+	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+			  "\n**** Exception %s during execution of method ",
+			  acpi_format_exception(status)));
+
+	acpi_ds_print_node_pathname(walk_state->method_node, NULL);
+
+	/* Display stack of executing methods */
+
+	ACPI_DEBUG_PRINT_RAW((ACPI_DB_DISPATCH,
+			      "\n\nMethod Execution Stack:\n"));
+	next_walk_state = thread->walk_state_list;
+
+	/* Walk list of linked walk states */
+
+	while (next_walk_state) {
+		method_desc = next_walk_state->method_desc;
+		if (method_desc) {
+			acpi_ex_stop_trace_method((struct acpi_namespace_node *)
+						  method_desc->method.node,
+						  method_desc, walk_state);
+		}
+
+		ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
+				  "    Method [%4.4s] executing: ",
+				  acpi_ut_get_node_name(next_walk_state->
+							method_node)));
+
+		/* First method is the currently executing method */
+
+		if (next_walk_state == walk_state) {
+			if (op) {
+
+				/* Display currently executing ASL statement */
+
+				next = op->common.next;
+				op->common.next = NULL;
+
+#ifdef ACPI_DISASSEMBLER
+				if (walk_state->method_node !=
+				    acpi_gbl_root_node) {
+
+					/* More verbose if not module-level code */
+
+					acpi_os_printf("Failed at ");
+					acpi_dm_disassemble(next_walk_state, op,
+							    ACPI_UINT32_MAX);
+				}
+#endif
+				op->common.next = next;
+			}
+		} else {
+			/*
+			 * This method has called another method
+			 * NOTE: the method call parse subtree is already deleted at
+			 * this point, so we cannot disassemble the method invocation.
+			 */
+			ACPI_DEBUG_PRINT_RAW((ACPI_DB_DISPATCH,
+					      "Call to method "));
+			acpi_ds_print_node_pathname(previous_method, NULL);
+		}
+
+		previous_method = next_walk_state->method_node;
+		next_walk_state = next_walk_state->next;
+		ACPI_DEBUG_PRINT_RAW((ACPI_DB_DISPATCH, "\n"));
+	}
+
+	return_VOID;
+}
+
+#else
+void
+acpi_ds_dump_method_stack(acpi_status status,
+			  struct acpi_walk_state *walk_state,
+			  union acpi_parse_object *op)
+{
+	return;
+}
+
+#endif