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/usr/share/systemtap/runtime/linux

Name	Size	Mode	Actions
uprobes/	-	0755	rm
uprobes2/	-	0755	rm
access_process_vm.h	4311	0644	edit dl rm
addr-map.c	9749	0644	edit dl rm
alloc.c	15900	0644	edit dl rm
arith.c	16799	0644	edit dl rm
autoconf-514-panic.c	68	0644	edit dl rm
autoconf-access_ok_2args.c	90	0644	edit dl rm
autoconf-alloc-percpu-align.c	118	0644	edit dl rm
autoconf-asm-syscall.c	51	0644	edit dl rm
autoconf-atomic_fetch_add_unless.c	94	0644	edit dl rm
autoconf-bio-bi_opf.c	824	0644	edit dl rm
autoconf-blk-types.c	359	0644	edit dl rm
autoconf-compat-utimbuf.c	53	0644	edit dl rm
autoconf-compat_sigaction.c	448	0644	edit dl rm
autoconf-constant-tsc.c	63	0644	edit dl rm
autoconf-cpu-clock.c	1277	0644	edit dl rm
autoconf-dpath-path.c	121	0644	edit dl rm
autoconf-files_lookup_fd_raw.c	136	0644	edit dl rm
autoconf-from_kuid_munged.c	191	0644	edit dl rm
autoconf-fs_supers-hlist.c	354	0644	edit dl rm
autoconf-generated-compile.c	56	0644	edit dl rm
autoconf-genhd.c	201	0644	edit dl rm
autoconf-get-kretprobe.c	107	0644	edit dl rm
autoconf-get_user_pages-flags.c	1549	0644	edit dl rm
autoconf-get_user_pages-notask_struct.c	1301	0644	edit dl rm
autoconf-get_user_pages_remote-flags.c	1550	0644	edit dl rm
autoconf-get_user_pages_remote-flags_locked.c	1331	0644	edit dl rm
autoconf-get_user_pages_remote-notask_struct.c	1438	0644	edit dl rm
autoconf-grsecurity.c	219	0644	edit dl rm
autoconf-hlist-4args.c	296	0644	edit dl rm
autoconf-hlist_add_tail_rcu.c	112	0644	edit dl rm
autoconf-hrtimer-getset-expires.c	126	0644	edit dl rm
autoconf-hrtimer-rel.c	87	0644	edit dl rm
autoconf-hw_breakpoint_context.c	315	0644	edit dl rm
autoconf-inode-private.c	173	0644	edit dl rm
autoconf-inode-rwsem.c	172	0644	edit dl rm
autoconf-inode-uretprobes.c	264	0644	edit dl rm
autoconf-kernel_read-new-args.c	1030	0644	edit dl rm
autoconf-kprobe-symbol-name.c	90	0644	edit dl rm
autoconf-ktime-get-real.c	98	0644	edit dl rm
autoconf-linux-sched_headers.c	1678	0644	edit dl rm
autoconf-local-clock.c	1282	0644	edit dl rm
autoconf-lockdown-debugfs.c	102	0644	edit dl rm
autoconf-lockdown-kernel.c	90	0644	edit dl rm
autoconf-mm-context-vdso-base.c	117	0644	edit dl rm
autoconf-mm-context-vdso.c	114	0644	edit dl rm
autoconf-mm-shmempages.c	72	0644	edit dl rm
autoconf-mmap_lock.c	175	0644	edit dl rm
autoconf-module-sect-attrs.c	158	0644	edit dl rm
autoconf-module_layout.c	52	0644	edit dl rm
autoconf-mod_kallsyms.c	51	0644	edit dl rm
autoconf-nameidata.c	96	0644	edit dl rm
autoconf-netfilter-4_1.c	769	0644	edit dl rm
autoconf-netfilter-4_4.c	1460	0644	edit dl rm
autoconf-netfilter-313b.c	602	0644	edit dl rm
autoconf-netfilter.c	422	0644	edit dl rm
autoconf-old-inode-uprobes.c	357	0644	edit dl rm
autoconf-oneachcpu-retry.c	957	0644	edit dl rm
autoconf-pagefault_disable.c	137	0644	edit dl rm
autoconf-pde_data.c	226	0644	edit dl rm
autoconf-perf-structpid.c	444	0644	edit dl rm
autoconf-procfs-owner.c	158	0644	edit dl rm
autoconf-proc_ops.c	566	0644	edit dl rm
autoconf-rcu_is_watching.c	385	0644	edit dl rm
autoconf-real-parent.c	427	0644	edit dl rm
autoconf-regset.c	239	0644	edit dl rm
autoconf-relay-umode_t.c	730	0644	edit dl rm
autoconf-relay_buf-per_cpu_ptr.c	920	0644	edit dl rm
autoconf-ring_buffer-flags.c	112	0644	edit dl rm
autoconf-ring_buffer_lost_events.c	296	0644	edit dl rm
autoconf-ring_buffer_read_prepare.c	181	0644	edit dl rm
autoconf-save-stack-trace-no-bp.c	498	0644	edit dl rm
autoconf-save-stack-trace.c	501	0644	edit dl rm
autoconf-set_fs.c	221	0644	edit dl rm
autoconf-smpcall-4args.c	166	0644	edit dl rm
autoconf-smpcall-5args.c	169	0644	edit dl rm
autoconf-stack-trace-save-regs.c	176	0644	edit dl rm
autoconf-stacktrace_ops-int-address.c	409	0644	edit dl rm
autoconf-stacktrace_ops-warning.c	188	0644	edit dl rm
autoconf-syscall_get_args_3args.c	239	0644	edit dl rm
autoconf-task-state.c	550	0644	edit dl rm
autoconf-task-uid.c	152	0644	edit dl rm
autoconf-task_work-struct.c	219	0644	edit dl rm
autoconf-time32-old.c	52	0644	edit dl rm
autoconf-time32.c	53	0644	edit dl rm
autoconf-timerfd.c	232	0644	edit dl rm
autoconf-trace-printk.c	151	0644	edit dl rm
autoconf-tracepoint-has-data.c	493	0644	edit dl rm
autoconf-tracepoint-strings.c	233	0644	edit dl rm
autoconf-uaccess.c	28	0644	edit dl rm
autoconf-uapi-mount.c	52	0644	edit dl rm
autoconf-udelay_simple.c	90	0644	edit dl rm
autoconf-uidgid.c	50	0644	edit dl rm
autoconf-unwind-stack-trace.c	326	0644	edit dl rm
autoconf-uprobe-get-pc.c	374	0644	edit dl rm
autoconf-utrace-regset.c	273	0644	edit dl rm
autoconf-utrace-via-tracepoints.c	1712	0644	edit dl rm
autoconf-vm-area-pte.c	141	0644	edit dl rm
autoconf-walk-stack.c	217	0644	edit dl rm
autoconf-x86-fs.c	90	0644	edit dl rm
autoconf-x86-gs.c	90	0644	edit dl rm
autoconf-x86-uniregs.c	140	0644	edit dl rm
autoconf-x86-xfs.c	91	0644	edit dl rm
common_session_state.h	3249	0644	edit dl rm
compat_net.h	858	0644	edit dl rm
compat_structs.h	4409	0644	edit dl rm
compat_unistd.h	68384	0644	edit dl rm
copy.c	2717	0644	edit dl rm
debug.h	2978	0644	edit dl rm
io.c	5291	0644	edit dl rm
itrace.c	14874	0644	edit dl rm
kprobes.c	25126	0644	edit dl rm
loc2c-runtime.h	29874	0644	edit dl rm
map_list.h	1220	0644	edit dl rm
map_runtime.h	5266	0644	edit dl rm
namespaces.h	7128	0644	edit dl rm
netfilter.c	1410	0644	edit dl rm
perf.c	7596	0644	edit dl rm
perf.h	1272	0644	edit dl rm
perf_event_counter_context.c	336	0644	edit dl rm
perf_probe_handler_nmi.c	278	0644	edit dl rm
perf_read.h	959	0644	edit dl rm
print.c	11402	0644	edit dl rm
probe_lock.h	1807	0644	edit dl rm
regs-ia64.c	3741	0644	edit dl rm
regs.c	13490	0644	edit dl rm
runtime.h	12591	0644	edit dl rm
runtime_context.h	6089	0644	edit dl rm
runtime_defines.h	1041	0644	edit dl rm
stap_mmap_lock.h	343	0644	edit dl rm
stat_runtime.h	1774	0644	edit dl rm
stp_tls.h	1181	0644	edit dl rm
stp_tracepoint.c	11481	0644	edit dl rm
stp_tracepoint.h	2270	0644	edit dl rm
syscalls-common.h	976	0644	edit dl rm
task_finder.c	53860	0644	edit dl rm
task_finder2.c	57640	0644	edit dl rm
task_finder_map.c	5194	0644	edit dl rm
task_finder_stubs.c	2442	0644	edit dl rm
task_work_compatibility.h	1283	0644	edit dl rm
timer.c	2200	0644	edit dl rm
timer.h	1383	0644	edit dl rm
timer_compatibility.h	2317	0644	edit dl rm
uprobes-common.c	15573	0644	edit dl rm
uprobes-common.h	1653	0644	edit dl rm
uprobes-inc.h	484	0644	edit dl rm
uprobes-inode.c	34086	0644	edit dl rm

Edit: /usr/share/systemtap/runtime/linux/addr-map.c (9749B)

/* -*- linux-c -*- 
 * Map of addresses to disallow.
 * Copyright (C) 2005-2019 Red Hat Inc.
 *
 * This file is part of systemtap, and is free software.  You can
 * redistribute it and/or modify it under the terms of the GNU General
 * Public License (GPL); either version 2, or (at your option) any
 * later version.
 */

#ifndef _STAPLINUX_ADDR_MAP_C_
#define _STAPLINUX_ADDR_MAP_C_ 1

/** @file addr-map
 * @brief Implements functions used by the deref macro to blocklist
 * certain addresses.
 */

// PR12970 (populate runtime/bad-addr database) hasn't been
// fixed. Until we're ready to populate the bad address database,
// let's provide a "junior" version of lookup_bad_addr(), since that
// will allow us to skip grabbing the lock and searching the empty
// list.
//
// See <https://sourceware.org/bugzilla/show_bug.cgi?id=12970> for
// more details.

#include <linux/uaccess.h>

#ifndef PR12970

#if ! STP_PRIVILEGE_CONTAINS (STP_PRIVILEGE, STP_PR_STAPDEV) && \
    ! STP_PRIVILEGE_CONTAINS (STP_PRIVILEGE, STP_PR_STAPSYS)
#include <asm/processor.h> /* For TASK_SIZE */
#endif

#ifdef STAPCONF_ACCESS_OK_2ARGS
#define stp_access_ok(x,y,z) access_ok(y,z)
#else
#define stp_access_ok(x,y,z) access_ok(x,y,z)
#endif

static int
lookup_bad_addr_user(const int type, const unsigned long addr, const size_t size)
{
  /* Is this a valid memory access?
   * 
   * Note we're using stp_access_ok() here. This is only supposed to be
   * called when we're in task context. Occasionally lookup_bad_addr()
   * gets called when not in task context. If in_task() exists, only
   * call stp_access_ok() when we're in task context (otherwise we'll get
   * a kernel warning). If we aren't in task context, we'll just do a
   * range check.
   */
#if !defined(in_task)
  if (size == 0 || ULONG_MAX - addr < size - 1
      || !stp_access_ok(type, (void *)addr, size))
    return 1;
#else
  if (size == 0 || ULONG_MAX - addr < size - 1
      || (in_task() && !stp_access_ok(type, (void *)addr, size))
      || (!in_task()
#if defined(user_addr_max)
	  && ((user_addr_max() - size) < addr)
#endif
	      ))
    return 1;
#endif

#if ! STP_PRIVILEGE_CONTAINS (STP_PRIVILEGE, STP_PR_STAPDEV) && \
    ! STP_PRIVILEGE_CONTAINS (STP_PRIVILEGE, STP_PR_STAPSYS)
  /* Unprivileged users must not access memory while the context
     does not refer to their own process.  */
  if (! is_myproc ())
    return 1;
  /* Unprivileged users must not access kernel space memory.  */
  if (addr + size > TASK_SIZE)
    return 1;
#endif

return 0;
}

static int
lookup_bad_addr(const int type, const unsigned long addr, const size_t size,
                const stp_mm_segment_t seg)
{
#ifndef STAPCONF_SET_FS
  /* Is this a valid memory access?
   *
   * PR26811: Since kernel 5.10 due to set_fs() removal we need to
   * distinguish kernel- and user-space addresses when asking this
   * question.
   */
  if (!MM_SEG_IS_KERNEL(seg))
    return lookup_bad_addr_user(type, addr, size);

/* For kernel addr, skip the in_task() portion of the address checks: */
  if (size == 0 || ULONG_MAX - addr < size - 1)
    return 1;

/* XXX: Kernel reads call copy_from_kernel_nofault() which also
     checks copy_from_kernel_fault_allowed(),
     currently a stub function returning true -- not worth invoking
     ourselves through kallsyms. Keep an eye on this, though. */

return 0;
#else
  /* XXX: On earlier kernels the same logic works for kernel-space: */
  return lookup_bad_addr_user(type, addr, size);
#endif
}

#else /* PR12970 */

struct addr_map_entry
{
  unsigned long min;
  unsigned long max;
};

struct addr_map
{
  size_t size;
  struct addr_map_entry entries[0];
};

static STP_DEFINE_RWLOCK(addr_map_lock);
static struct addr_map* blockmap;

/* Find address of entry where we can insert a new one. */
static size_t
upper_bound(unsigned long addr, struct addr_map* map)
{
  size_t start = 0;
  size_t end = map->size;
  struct addr_map_entry *entry = 0;

if (end == 0)
    return 0;
  do
    {
      size_t new_idx;
      if (addr < map->entries[start].min)
        return start;
      if (addr >= map->entries[end-1].max)
        return end;
      new_idx = (end + start) / 2;
      entry = &map->entries[new_idx];
      if (addr < entry->min)
        end = new_idx;
      else
        start = new_idx + 1;
    } while (end != start);
  return entry - &map->entries[0];
}

/* Search for an entry in the given map which overlaps the range specified by
   addr and size.  */
static struct addr_map_entry*
lookup_addr_aux(unsigned long addr, size_t size, struct addr_map* map)
{
  size_t start = 0;
  size_t end;

/* No map? No matching entry. */
  if (!map)
    return 0;
  /* Empty map? No matching entry.  */
  if (map->size == 0)
    return 0;

/* Use binary search on the sorted map entries.  */
  end = map->size;
  do
    {
      int entry_idx;
      struct addr_map_entry *entry = 0;
      /* If the target range is beyond those of the remaining entries in the
	 map, then a matching entry will not be found  */
      if (addr + size <= map->entries[start].min ||
	  addr >= map->entries[end - 1].max)
        return 0;
      /* Choose the map entry at the mid point of the remaining entries.  */
      entry_idx = (end + start) / 2;
      entry = &map->entries[entry_idx];
      /* If our range overlaps the range of this entry, then we have a match. */
      if (addr + size > entry->min && addr < entry->max)
        return entry;
      /* If our range is below the range of this entry, then cull the entries
	 above this entry, otherwise cull the entries below it.  */
      if (addr + size <= entry->min)
        end = entry_idx;
      else
        start = entry_idx + 1;
    } while (start < end);
  return 0;
}

#if ! STP_PRIVILEGE_CONTAINS (STP_PRIVILEGE, STP_PR_STAPDEV) && \
    ! STP_PRIVILEGE_CONTAINS (STP_PRIVILEGE, STP_PR_STAPSYS)
#include <asm/processor.h> /* For TASK_SIZE */
#endif

static int
lookup_bad_addr(const int type, const unsigned long addr, const size_t size)
{
  struct addr_map_entry* result = 0;
  unsigned long flags;

/* Is this a valid memory access?  */
  if (size == 0 || ULONG_MAX - addr < size - 1
      || !stp_access_ok(type, (void *)addr, size))
    return 1;

/* Search for the given range in the block-listed map.  */
  stp_read_lock_irqsave(&addr_map_lock, flags);
  result = lookup_addr_aux(addr, size, blockmap);
  stp_read_unlock_irqrestore(&addr_map_lock, flags);
  if (result)
    return 1;
  else
    return 0;
}

static int
add_bad_addr_entry(unsigned long min_addr, unsigned long max_addr,
                   struct addr_map_entry** existing_min,
                   struct addr_map_entry** existing_max)
{
  struct addr_map* new_map = 0;
  struct addr_map* old_map = 0;
  struct addr_map_entry* min_entry = 0;
  struct addr_map_entry* max_entry = 0;
  struct addr_map_entry* new_entry = 0;
  size_t existing = 0;
  unsigned long flags;

/* Loop allocating memory for a new entry in the map. */
  while (1)
    {
      size_t old_size = 0;
      stp_write_lock_irqsave(&addr_map_lock, flags);
      old_map = blockmap;
      if (old_map)
        old_size = old_map->size;
      /* Either this is the first time through the loop, or we
         allocated a map previous time, but someone has come in and
         added an entry while we were sleeping. */
      if (!new_map || (new_map && new_map->size < old_size + 1))
        {
          stp_write_unlock_irqrestore(&addr_map_lock, flags);
          if (new_map)
            {
	      _stp_kfree(new_map);
              new_map = 0;
            }
          new_map = _stp_kmalloc(sizeof(*new_map)
				 + sizeof(*new_entry) * (old_size + 1));
          if (!new_map)
            return -ENOMEM;
          new_map->size = old_size + 1;
        }
      else
        break;
    }
  if (!blockmap)
    {
      existing = 0;
    }
  else
    {
      min_entry = lookup_addr_aux(min_addr, 1, blockmap);
      max_entry = lookup_addr_aux(max_addr, 1, blockmap);
      if (min_entry || max_entry)
        {
          if (existing_min)
            *existing_min = min_entry;
          if (existing_max)
            *existing_max = max_entry;
          stp_write_unlock_irqrestore(&addr_map_lock, flags);
          _stp_kfree(new_map);
          return 1;
        }
      existing = upper_bound(min_addr, old_map);
    }
  new_entry = &new_map->entries[existing];
  new_entry->min = min_addr;
  new_entry->max = max_addr;
  if (old_map)
    {
      memcpy(&new_map->entries, old_map->entries,
             existing * sizeof(*new_entry));
      if (old_map->size > existing)
        memcpy(new_entry + 1, &old_map->entries[existing],
               (old_map->size - existing) * sizeof(*new_entry));
    }
  blockmap = new_map;
  stp_write_unlock_irqrestore(&addr_map_lock, flags);
  if (old_map)
    _stp_kfree(old_map);
  return 0;
}

static void
delete_bad_addr_entry(struct addr_map_entry* entry)
{
}

#endif /* PR12970 */

#endif /* _STAPLINUX_ADDR_MAP_C_ */

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