Slightly improving `buddydump` + deprecating `pcplist` (#3015)

* fixed buddydump behaviours and made test more comprehensive

* handling new name

* changing to tuple instead

* added comment to test

pwndbg/commands/buddydump.py

@@ -122,7 +122,7 @@ def check_find(counter: int, physmap_addr: int, pba: ParsedBuddyArgs, cbp: Curre
     if pba.find is None:
         return False
     start = physmap_addr
-    end = physmap_addr + (1 << cbp.order)
+    end = physmap_addr + 0x1000 * (1 << cbp.order)
     return pba.find >= start and pba.find < end
 
 
@@ -343,5 +343,5 @@ def buddydump(
             print_pcp_set(pba, cbp)
             if not pcp_only:
                 print_free_area(pba, cbp)
-        if not cbp.found:
-            log.warning("No free pages with specified filters found.")
+    if not cbp.found:
+        log.warning("No free pages with specified filters found.")

pwndbg/dbg/gdb/__init__.py

@@ -1431,6 +1431,11 @@ class GDB(pwndbg.dbg_mod.Debugger):
                 f"alias -a {deprecated_cmd} = echo Use `{fixed_cmd}` instead (Pwndbg changed `_` to `-` in command names)\\n"
             )
 
+        for deprecated_cmd, new_cmd in (("pcplist", "buddydump"),):
+            gdb.execute(
+                f"alias -a {deprecated_cmd} = echo deprecation warning for old name, use `{new_cmd}` instead\\n"
+            )
+
         # This may throw an exception, see pwndbg/pwndbg#27
         try:
             gdb.execute("set disassembly-flavor intel")

tests/qemu-tests/tests/system/test_commands_kernel.py

@@ -1,5 +1,8 @@
 from __future__ import annotations
 
+import random
+import re
+
 import gdb
 import pytest
 
@@ -90,8 +93,6 @@ def test_x64_extra_registers_under_kernel_mode():
 def get_slab_object_address():
     """helper function to get the address of some kmalloc slab object
     and the associated slab cache name"""
-    import re
-
     caches = pwndbg.aglib.kernel.slab.caches()
     for cache in caches:
         cache_name = cache.name
@@ -135,6 +136,42 @@ def test_command_msr_write():
 )
 def test_command_buddydump():
     res = gdb.execute("buddydump", to_string=True)
-    assert (
-        "Order" in res and "Zone" in res and ("per_cpu_pageset" in res or "free_area" in res)
-    ) or res == "WARNING: Symbol 'node_data' not found\n"
+    NOFREEPAGE = "No free pages with specified filters found.\n"
+    if res == "WARNING: Symbol 'node_data' not found\n" or NOFREEPAGE == res:
+        return
+    # this indicates the buddy allocator contains at least one entry
+    assert "Order" in res and "Zone" in res and ("per_cpu_pageset" in res or "free_area" in res)
+
+    ansi_escape = re.compile(r"\x1b\[[0-9;]*m")
+    res = ansi_escape.sub("", res)
+    # find the starting addresses of all entries within the freelists
+    matches = re.findall(r"\[0x[0-9a-fA-F\-]{2}\] (0x[0-9a-fA-F]{16})", res)
+    for i in range(0, len(matches), 20):
+        # check every 20 elements so tests do not take too long
+        match = int(matches[i], 16)
+        res = gdb.execute(f"bud -f {hex(match + random.randint(0, 0x1000 - 1))}", to_string=True)
+        res = ansi_escape.sub("", res)
+        _matches = re.findall(r"\[0x[0-9a-fA-F\-]{2}\] (0x[0-9a-fA-F]{16})", res)
+        # asserting `bud -f` behaviour -- should be able to find the corresponding entry to an address
+        # even if the address is not aligned
+        assert len(_matches) == 1 and int(_matches[0], 16) == match
+
+    # nonexistent node index should not contain any entries
+    no_output = gdb.execute("buddydump -n 10", to_string=True)
+    assert NOFREEPAGE == no_output
+
+    # below checks are for filters
+    # for example, if a zone name is specified, other zones should not be present
+    filter_res = gdb.execute("bud -z DMA", to_string=True)
+    for name in ["DMA32", "Normal", "HighMem", "Movable", "Device"]:
+        assert f"Zone {name}" not in filter_res
+    filter_res = gdb.execute("bud -m Unmovable", to_string=True)
+    for name in ["Movable", "Reclaimable", "HighAtomic", "CMA", "Isolate"]:
+        assert f"- {name}" not in filter_res
+    filter_res = gdb.execute("bud -o 1", to_string=True)
+    for i in range(11):
+        if i == 1:
+            continue
+        assert f"Order {i}" not in filter_res
+    filter_res = gdb.execute("bud -p", to_string=True)
+    assert "free_area" not in filter_res