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machine__init() always returns 0 even when memory allocation fails, because commit81f981d7ec("perf machine: Free root_dir in machine__init() error path") introduced 'int err = -ENOMEM' and an error cleanup path but left the final 'return 0' instead of 'return err'. Fix by returning err, check the return value in __machine__new_host() which was ignoring it, and change machines__init() from void to int so it too can propagate the error to perf_session__new(), aslr_tool__init() and test callers. The error cleanup also used zfree(&machine->kmaps), but kmaps is a refcounted maps structure — use maps__zput() to properly drop the reference, matching machine__exit(). Move dsos__init() and threads__init() before the first fallible allocation (maps__new) so that machine__exit() is safe to call on any machine struct that machine__init() touched, even on early failure. Fixes:81f981d7ec("perf machine: Free root_dir in machine__init() error path") Reported-by: sashiko-bot <sashiko-bot@kernel.org> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Assisted-by: Claude:claude-opus-4.6 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
1410 lines
40 KiB
C
1410 lines
40 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include "aslr.h"
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#include "addr_location.h"
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#include "debug.h"
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#include "event.h"
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#include "evsel.h"
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#include "evlist.h"
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#include "machine.h"
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#include "map.h"
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#include "thread.h"
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#include "tool.h"
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#include "session.h"
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#include "data.h"
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#include "dso.h"
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#include "pmus.h"
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#include <internal/lib.h> /* page_size */
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#include <linux/compiler.h>
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#include <linux/zalloc.h>
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#include <errno.h>
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#include <inttypes.h>
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#include <unistd.h>
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#include <byteswap.h>
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/**
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* struct remap_addresses_key - Key for mapping original addresses to remapped ones.
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* @dso: Pointer to the DSO (Dynamic Shared Object) associated with the mapping.
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* @invariant: Unique offset invariant within the VMA (Virtual Memory Area).
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* Calculated as `start - pgoff`. This value remains constant when
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* perf's internal `maps__fixup_overlap_and_insert` splits a map into
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* fragmented VMA pieces due to overlapping events, allowing us to
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* resolve split maps consistently back to the original VMA.
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* @pid: Process ID associated with the mapping.
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*/
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struct remap_addresses_key {
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struct machine *machine;
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struct dso *dso;
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u64 invariant;
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pid_t pid;
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};
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struct aslr_mapping {
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struct list_head node;
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u64 orig_start;
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u64 len;
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u64 remap_start;
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};
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struct aslr_evsel_priv {
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u64 orig_sample_type;
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u64 orig_sample_regs_user;
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u64 orig_sample_regs_intr;
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int orig_sample_size;
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};
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static size_t evsel_hash(long key, void *ctx __maybe_unused)
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{
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return (size_t)key;
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}
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static bool evsel_equal(long key1, long key2, void *ctx __maybe_unused)
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{
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return key1 == key2;
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}
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struct process_top_address {
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u64 remapped_max;
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};
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struct aslr_tool {
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/** @tool: The tool implemented here and a pointer to a delegate to process the data. */
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struct delegate_tool tool;
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/** @machines: The machines with the input, not remapped, virtual address layout. */
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struct machines machines;
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/** @event_copy: Buffer used to create an event to pass to the delegate. */
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char event_copy[PERF_SAMPLE_MAX_SIZE] __aligned(8);
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/** @remap_addresses: mapping from remap_addresses_key to remapped address. */
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struct hashmap remap_addresses;
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/** @top_addresses: mapping from process to max remapped address. */
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struct hashmap top_addresses;
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/**
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* @evsel_orig_attrs: mapping from evsel pointer to its original
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* unstripped sample_type and registers bitmasks.
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*/
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struct hashmap evsel_orig_attrs;
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};
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static const pid_t kernel_pid = -1;
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/* Start remapping user processes from a small non-zero offset. */
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static const u64 user_space_start = 0x200000;
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static const u64 kernel_space_start_64 = 0xffff800010000000ULL;
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static const u64 kernel_space_start_32 = 0x80000000ULL;
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static size_t remap_addresses__hash(long _key, void *ctx __maybe_unused)
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{
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struct remap_addresses_key *key = (struct remap_addresses_key *)_key;
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void *dso_ptr = key->dso ? RC_CHK_ACCESS(key->dso) : NULL;
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return (size_t)key->machine ^ (size_t)dso_ptr ^ key->invariant ^ key->pid;
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}
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static bool remap_addresses__equal(long _key1, long _key2, void *ctx __maybe_unused)
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{
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struct remap_addresses_key *key1 = (struct remap_addresses_key *)_key1;
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struct remap_addresses_key *key2 = (struct remap_addresses_key *)_key2;
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return key1->machine == key2->machine &&
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RC_CHK_EQUAL(key1->dso, key2->dso) &&
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key1->invariant == key2->invariant &&
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key1->pid == key2->pid;
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}
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struct top_addresses_key {
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struct machine *machine;
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pid_t pid;
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};
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static size_t top_addresses__hash(long _key, void *ctx __maybe_unused)
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{
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struct top_addresses_key *key = (struct top_addresses_key *)_key;
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return (size_t)key->machine ^ key->pid;
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}
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static bool top_addresses__equal(long _key1, long _key2, void *ctx __maybe_unused)
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{
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struct top_addresses_key *key1 = (struct top_addresses_key *)_key1;
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struct top_addresses_key *key2 = (struct top_addresses_key *)_key2;
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return key1->machine == key2->machine && key1->pid == key2->pid;
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}
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static u64 round_up_to_page_size(u64 addr)
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{
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return (addr + page_size - 1) & ~((u64)page_size - 1);
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}
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static u64 aslr_tool__remap_address(struct aslr_tool *aslr,
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struct thread *aslr_thread,
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u8 cpumode,
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u64 addr)
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{
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struct addr_location al;
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struct remap_addresses_key key;
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u64 *remapped_invariant_ptr = NULL;
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u64 remap_addr = 0;
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u8 effective_cpumode = cpumode;
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struct dso *dso;
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const char *dso_name;
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if (!aslr_thread)
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return 0; /* No thread. */
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addr_location__init(&al);
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if (!thread__find_map(aslr_thread, cpumode, addr, &al)) {
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/*
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* If lookup fails with specified cpumode, try fallback to the other space
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* to be robust against bad cpumode in samples.
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*/
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if (cpumode == PERF_RECORD_MISC_KERNEL)
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effective_cpumode = PERF_RECORD_MISC_USER;
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else if (cpumode == PERF_RECORD_MISC_USER)
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effective_cpumode = PERF_RECORD_MISC_KERNEL;
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else if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL)
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effective_cpumode = PERF_RECORD_MISC_GUEST_USER;
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else if (cpumode == PERF_RECORD_MISC_GUEST_USER)
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effective_cpumode = PERF_RECORD_MISC_GUEST_KERNEL;
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if (!thread__find_map(aslr_thread, effective_cpumode, addr, &al)) {
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addr_location__exit(&al);
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return 0; /* No mmap. */
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}
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}
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dso = map__dso(al.map);
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dso_name = dso ? dso__long_name(dso) : NULL;
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key.machine = maps__machine(thread__maps(aslr_thread));
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key.dso = dso;
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if (dso && !is_anon_memory(dso_name) && !is_no_dso_memory(dso_name))
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key.invariant = map__start(al.map) - map__pgoff(al.map);
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else
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key.invariant = map__start(al.map);
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key.pid = (effective_cpumode == PERF_RECORD_MISC_KERNEL ||
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effective_cpumode == PERF_RECORD_MISC_GUEST_KERNEL) ?
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kernel_pid : thread__pid(aslr_thread);
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if (hashmap__find(&aslr->remap_addresses, &key, &remapped_invariant_ptr)) {
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remap_addr = *remapped_invariant_ptr + map__pgoff(al.map) +
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(addr - map__start(al.map));
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} else {
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pr_debug("Cannot find a remapped entry for address %" PRIx64 " in mapping %" PRIx64 "(%zu) for pid=%d\n",
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addr, map__start(al.map), map__size(al.map), key.pid);
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}
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addr_location__exit(&al);
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return remap_addr;
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}
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struct aslr_machine_priv {
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bool kernel_maps_loaded;
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};
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static int aslr_tool__preload_kernel_maps(struct machine *machine)
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{
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struct aslr_machine_priv *mpriv = machine->priv;
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if (!mpriv) {
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mpriv = zalloc(sizeof(*mpriv));
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if (!mpriv)
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return -ENOMEM;
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machine->priv = mpriv;
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}
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if (!mpriv->kernel_maps_loaded) {
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struct maps *kmaps = machine__kernel_maps(machine);
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if (kmaps) {
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int err = maps__load_maps(kmaps);
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if (err < 0) {
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pr_err("ASLR: Failed to preload kernel maps for machine pid %d\n",
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machine->pid);
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return err;
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}
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}
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mpriv->kernel_maps_loaded = true;
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}
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return 0;
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}
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static void aslr_tool__free_machine_priv(struct machine *machine)
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{
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free(machine->priv);
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machine->priv = NULL;
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}
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static void aslr_tool__destroy_machines_priv(struct machines *machines)
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{
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struct rb_node *nd;
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aslr_tool__free_machine_priv(&machines->host);
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for (nd = rb_first_cached(&machines->guests); nd; nd = rb_next(nd)) {
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struct machine *machine = rb_entry(nd, struct machine, rb_node);
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aslr_tool__free_machine_priv(machine);
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}
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}
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static u64 aslr_tool__findnew_mapping(struct aslr_tool *aslr,
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struct machine *session_machine,
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struct thread *aslr_thread,
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u8 cpumode, u64 start,
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u64 len, u64 pgoff)
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{
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/* Address location for dso lookup. */
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struct addr_location al;
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/* Original ASLR address based key for the remap table. */
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struct remap_addresses_key remap_key;
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/* The address in the ASLR sanitized address space less pg_off. */
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u64 *remapped_invariant_ptr;
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/* Key for the maximum address in a process. */
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struct top_addresses_key top_addr_key;
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/* Value in top address table. */
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struct process_top_address *top = NULL;
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/* Address in ASLR sanitized address space. */
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u64 remap_addr;
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/* Potentially allocated remap table key. */
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struct remap_addresses_key *new_remap_key = NULL;
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/*
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* Potentially allocated remap table key.
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* TODO: Avoid allocation necessary for perf 32-bit binary support.
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*/
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u64 *new_remap_val = NULL;
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int err;
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if (!aslr_thread)
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return 0;
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/* The key to look up an incoming address to the outgoing value. */
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addr_location__init(&al);
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remap_key.machine = maps__machine(thread__maps(aslr_thread));
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remap_key.pid = (cpumode == PERF_RECORD_MISC_KERNEL ||
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cpumode == PERF_RECORD_MISC_GUEST_KERNEL) ?
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kernel_pid : thread__pid(aslr_thread);
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if (thread__find_map(aslr_thread, cpumode, start, &al)) {
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struct dso *dso = map__dso(al.map);
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const char *dso_name = dso ? dso__long_name(dso) : NULL;
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remap_key.dso = dso;
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if (dso && !is_anon_memory(dso_name) && !is_no_dso_memory(dso_name))
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remap_key.invariant = map__start(al.map) - map__pgoff(al.map);
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else
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remap_key.invariant = map__start(al.map);
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} else {
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remap_key.dso = NULL;
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remap_key.invariant = start;
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}
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/* The key to look up top allocated address. */
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top_addr_key.machine = remap_key.machine;
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top_addr_key.pid = remap_key.pid;
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if (hashmap__find(&aslr->remap_addresses, &remap_key, &remapped_invariant_ptr)) {
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/* Mmap already exists. */
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u64 calculated_max;
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if (al.map) {
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/*
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* The cached value is the base of the invariant. We add the
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* offset into the VMA (start - map__start), plus the map's
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* pgoff, to get the precise virtual address within this chunk.
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*/
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remap_addr = *remapped_invariant_ptr + map__pgoff(al.map) +
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(start - map__start(al.map));
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} else {
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/*
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* For unmapped memory (e.g. kernel anonymous), the cached value
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* was stored offset by pgoff. Adding pgoff yields the true remap_addr.
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*/
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remap_addr = *remapped_invariant_ptr + pgoff;
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}
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calculated_max = remap_addr + len;
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/* See if top mapping was expanded. */
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if (hashmap__find(&aslr->top_addresses, &top_addr_key, &top)) {
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if (calculated_max > top->remapped_max)
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top->remapped_max = calculated_max;
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}
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addr_location__exit(&al);
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return remap_addr;
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}
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/* No mmap, create an entry from the top address. */
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if (hashmap__find(&aslr->top_addresses, &top_addr_key, &top)) {
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struct addr_location prev_al;
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bool is_contiguous = false;
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/* Current max allocated mmap address within the process. */
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remap_addr = top->remapped_max;
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addr_location__init(&prev_al);
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if (thread__find_map(aslr_thread, cpumode, start - 1, &prev_al)) {
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if (map__end(prev_al.map) == start)
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is_contiguous = true;
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}
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addr_location__exit(&prev_al);
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if (is_contiguous) {
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/* Contiguous mapping, do not add 1 page gap! */
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remap_addr = round_up_to_page_size(remap_addr);
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} else {
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/* Give 1 page gap from current max page. */
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remap_addr = round_up_to_page_size(remap_addr);
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remap_addr += page_size;
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}
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if (remap_addr + len > top->remapped_max)
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top->remapped_max = remap_addr + len;
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} else {
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/* First address of the process, allocate key and first top address. */
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struct top_addresses_key *tk;
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struct process_top_address *top_val;
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struct perf_env *env = session_machine ? session_machine->env : NULL;
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bool is_64 = env ? perf_env__kernel_is_64_bit(env) : (sizeof(void *) == 8);
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u64 kernel_start_addr = is_64 ? kernel_space_start_64 : kernel_space_start_32;
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remap_addr = (cpumode == PERF_RECORD_MISC_KERNEL ||
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cpumode == PERF_RECORD_MISC_GUEST_KERNEL) ?
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kernel_start_addr : user_space_start;
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remap_addr = round_up_to_page_size(remap_addr);
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tk = malloc(sizeof(*tk));
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top_val = malloc(sizeof(*top_val));
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if (!tk || !top_val) {
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err = -ENOMEM;
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} else {
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*tk = top_addr_key;
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top_val->remapped_max = remap_addr + len;
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err = hashmap__insert(&aslr->top_addresses, tk, top_val,
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HASHMAP_ADD, NULL, NULL);
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}
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if (err) {
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errno = -err;
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pr_err("Failure to add ASLR process top address %m\n");
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free(tk);
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free(top_val);
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addr_location__exit(&al);
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return 0;
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}
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}
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/* Create rmeapping entry. */
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new_remap_key = malloc(sizeof(*new_remap_key));
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new_remap_val = malloc(sizeof(u64));
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if (!new_remap_key || !new_remap_val) {
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err = -ENOMEM;
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} else {
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*new_remap_key = remap_key;
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new_remap_key->dso = dso__get(remap_key.dso);
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if (cpumode == PERF_RECORD_MISC_KERNEL ||
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cpumode == PERF_RECORD_MISC_GUEST_KERNEL) {
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if (al.map) {
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*new_remap_val = remap_addr -
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(start - map__start(al.map)) -
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map__pgoff(al.map);
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} else {
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/*
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* Subtract pgoff from the base virtual address so that
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* when the lookup path adds pgoff back, it perfectly
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* cancels out and returns remap_addr.
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*/
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*new_remap_val = remap_addr - pgoff;
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}
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} else {
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*new_remap_val = remap_addr - (al.map ? (start - map__start(al.map)) +
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map__pgoff(al.map) : pgoff);
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}
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err = hashmap__add(&aslr->remap_addresses, new_remap_key, new_remap_val);
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if (err)
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dso__put(new_remap_key->dso);
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}
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if (err) {
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errno = -err;
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pr_err("Failure to add ASLR remapping %m\n");
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free(new_remap_key);
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free(new_remap_val);
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addr_location__exit(&al);
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return 0;
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}
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addr_location__exit(&al);
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return remap_addr;
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}
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static int aslr_tool__process_mmap(const struct perf_tool *tool,
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union perf_event *event,
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struct perf_sample *sample,
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struct machine *machine)
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{
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struct delegate_tool *del_tool;
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struct aslr_tool *aslr;
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struct perf_tool *delegate;
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union perf_event *new_event;
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u8 cpumode;
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struct thread *thread;
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struct machine *aslr_machine;
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int err;
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del_tool = container_of(tool, struct delegate_tool, tool);
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aslr = container_of(del_tool, struct aslr_tool, tool);
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|
delegate = aslr->tool.delegate;
|
|
new_event = (union perf_event *)aslr->event_copy;
|
|
cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
|
|
|
|
aslr_machine = machines__findnew(&aslr->machines, machine->pid);
|
|
if (!aslr_machine)
|
|
return -ENOMEM;
|
|
if (aslr_tool__preload_kernel_maps(aslr_machine) < 0)
|
|
return -ENOMEM;
|
|
|
|
/* Create the thread, map, etc. in the ASLR before virtual address space. */
|
|
err = perf_event__process_mmap(tool, event, sample, aslr_machine);
|
|
if (err)
|
|
return err;
|
|
|
|
thread = machine__findnew_thread(aslr_machine, event->mmap.pid, event->mmap.tid);
|
|
if (!thread)
|
|
return -ENOMEM;
|
|
memcpy(&new_event->mmap, &event->mmap, event->mmap.header.size);
|
|
/* Remaps the mmap.start. */
|
|
new_event->mmap.start = aslr_tool__findnew_mapping(aslr, machine, thread, cpumode,
|
|
event->mmap.start,
|
|
event->mmap.len,
|
|
event->mmap.pgoff);
|
|
/*
|
|
* For anonymous memory (and kernel maps), the kernel populates the
|
|
* event's pgoff field with the original un-obfuscated virtual address
|
|
* in bytes (i.e. (addr >> PAGE_SHIFT) << PAGE_SHIFT).
|
|
* We must overwrite pgoff with the new remapped byte address to prevent
|
|
* leaking the original ASLR layout.
|
|
*/
|
|
if (is_anon_memory(event->mmap.filename) || is_no_dso_memory(event->mmap.filename) ||
|
|
((cpumode == PERF_RECORD_MISC_KERNEL || cpumode == PERF_RECORD_MISC_GUEST_KERNEL) &&
|
|
!is_kernel_module(event->mmap.filename, cpumode)))
|
|
new_event->mmap.pgoff = new_event->mmap.start;
|
|
err = delegate->mmap(delegate, new_event, sample, machine);
|
|
thread__put(thread);
|
|
return err;
|
|
}
|
|
|
|
static int aslr_tool__process_mmap2(const struct perf_tool *tool,
|
|
union perf_event *event,
|
|
struct perf_sample *sample,
|
|
struct machine *machine)
|
|
{
|
|
struct delegate_tool *del_tool;
|
|
struct aslr_tool *aslr;
|
|
struct perf_tool *delegate;
|
|
union perf_event *new_event;
|
|
u8 cpumode;
|
|
struct thread *thread;
|
|
struct machine *aslr_machine;
|
|
int err;
|
|
|
|
del_tool = container_of(tool, struct delegate_tool, tool);
|
|
aslr = container_of(del_tool, struct aslr_tool, tool);
|
|
delegate = aslr->tool.delegate;
|
|
new_event = (union perf_event *)aslr->event_copy;
|
|
cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
|
|
|
|
aslr_machine = machines__findnew(&aslr->machines, machine->pid);
|
|
if (!aslr_machine)
|
|
return -ENOMEM;
|
|
if (aslr_tool__preload_kernel_maps(aslr_machine) < 0)
|
|
return -ENOMEM;
|
|
|
|
/* Create the thread, map, etc. in the ASLR before virtual address space. */
|
|
err = perf_event__process_mmap2(tool, event, sample, aslr_machine);
|
|
if (err)
|
|
return err;
|
|
|
|
thread = machine__findnew_thread(aslr_machine, event->mmap2.pid, event->mmap2.tid);
|
|
if (!thread)
|
|
return -ENOMEM;
|
|
memcpy(&new_event->mmap2, &event->mmap2, event->mmap2.header.size);
|
|
/* Remaps the mmap.start. */
|
|
new_event->mmap2.start = aslr_tool__findnew_mapping(aslr, machine, thread, cpumode,
|
|
event->mmap2.start,
|
|
event->mmap2.len,
|
|
event->mmap2.pgoff);
|
|
/*
|
|
* For anonymous memory (and kernel maps), the kernel populates the
|
|
* event's pgoff field with the original un-obfuscated virtual address
|
|
* in bytes (i.e. (addr >> PAGE_SHIFT) << PAGE_SHIFT).
|
|
* We must overwrite pgoff with the new remapped byte address to prevent
|
|
* leaking the original ASLR layout.
|
|
*/
|
|
if (is_anon_memory(event->mmap2.filename) || is_no_dso_memory(event->mmap2.filename) ||
|
|
((cpumode == PERF_RECORD_MISC_KERNEL || cpumode == PERF_RECORD_MISC_GUEST_KERNEL) &&
|
|
!is_kernel_module(event->mmap2.filename, cpumode)))
|
|
new_event->mmap2.pgoff = new_event->mmap2.start;
|
|
err = delegate->mmap2(delegate, new_event, sample, machine);
|
|
thread__put(thread);
|
|
return err;
|
|
}
|
|
|
|
static int aslr_tool__process_comm(const struct perf_tool *tool,
|
|
union perf_event *event,
|
|
struct perf_sample *sample,
|
|
struct machine *machine)
|
|
{
|
|
struct delegate_tool *del_tool;
|
|
struct aslr_tool *aslr;
|
|
struct perf_tool *delegate;
|
|
struct machine *aslr_machine;
|
|
int err;
|
|
|
|
del_tool = container_of(tool, struct delegate_tool, tool);
|
|
aslr = container_of(del_tool, struct aslr_tool, tool);
|
|
delegate = aslr->tool.delegate;
|
|
|
|
aslr_machine = machines__findnew(&aslr->machines, machine->pid);
|
|
if (!aslr_machine)
|
|
return -ENOMEM;
|
|
if (aslr_tool__preload_kernel_maps(aslr_machine) < 0)
|
|
return -ENOMEM;
|
|
|
|
/* Create the thread, map, etc. in the ASLR before virtual address space. */
|
|
err = perf_event__process_comm(tool, event, sample, aslr_machine);
|
|
if (err)
|
|
return err;
|
|
|
|
return delegate->comm(delegate, event, sample, machine);
|
|
}
|
|
|
|
static int aslr_tool__process_fork(const struct perf_tool *tool,
|
|
union perf_event *event,
|
|
struct perf_sample *sample,
|
|
struct machine *machine)
|
|
{
|
|
struct delegate_tool *del_tool;
|
|
struct aslr_tool *aslr;
|
|
struct perf_tool *delegate;
|
|
struct machine *aslr_machine;
|
|
int err;
|
|
|
|
del_tool = container_of(tool, struct delegate_tool, tool);
|
|
aslr = container_of(del_tool, struct aslr_tool, tool);
|
|
delegate = aslr->tool.delegate;
|
|
|
|
aslr_machine = machines__findnew(&aslr->machines, machine->pid);
|
|
if (!aslr_machine)
|
|
return -ENOMEM;
|
|
if (aslr_tool__preload_kernel_maps(aslr_machine) < 0)
|
|
return -ENOMEM;
|
|
|
|
/* Create the thread, map, etc. in the ASLR before virtual address space. */
|
|
err = perf_event__process_fork(tool, event, sample, aslr_machine);
|
|
if (err)
|
|
return err;
|
|
|
|
return delegate->fork(delegate, event, sample, machine);
|
|
}
|
|
|
|
static int aslr_tool__process_exit(const struct perf_tool *tool,
|
|
union perf_event *event,
|
|
struct perf_sample *sample,
|
|
struct machine *machine)
|
|
{
|
|
struct delegate_tool *del_tool;
|
|
struct aslr_tool *aslr;
|
|
struct perf_tool *delegate;
|
|
struct machine *aslr_machine;
|
|
int err;
|
|
|
|
del_tool = container_of(tool, struct delegate_tool, tool);
|
|
aslr = container_of(del_tool, struct aslr_tool, tool);
|
|
delegate = aslr->tool.delegate;
|
|
|
|
aslr_machine = machines__findnew(&aslr->machines, machine->pid);
|
|
if (!aslr_machine)
|
|
return -ENOMEM;
|
|
if (aslr_tool__preload_kernel_maps(aslr_machine) < 0)
|
|
return -ENOMEM;
|
|
|
|
/* Create the thread, map, etc. in the ASLR before virtual address space. */
|
|
err = perf_event__process_exit(tool, event, sample, aslr_machine);
|
|
if (err)
|
|
return err;
|
|
|
|
return delegate->exit(delegate, event, sample, machine);
|
|
}
|
|
|
|
static int aslr_tool__process_text_poke(const struct perf_tool *tool __maybe_unused,
|
|
union perf_event *event __maybe_unused,
|
|
struct perf_sample *sample __maybe_unused,
|
|
struct machine *machine __maybe_unused)
|
|
{
|
|
/* Drop in case the instruction encodes an ASLR revealing address. */
|
|
return 0;
|
|
}
|
|
|
|
static int aslr_tool__process_ksymbol(const struct perf_tool *tool,
|
|
union perf_event *event,
|
|
struct perf_sample *sample,
|
|
struct machine *machine)
|
|
{
|
|
struct delegate_tool *del_tool;
|
|
struct aslr_tool *aslr;
|
|
struct perf_tool *delegate;
|
|
union perf_event *new_event;
|
|
struct thread *thread;
|
|
struct machine *aslr_machine;
|
|
bool is_unregister;
|
|
int err;
|
|
|
|
del_tool = container_of(tool, struct delegate_tool, tool);
|
|
aslr = container_of(del_tool, struct aslr_tool, tool);
|
|
delegate = aslr->tool.delegate;
|
|
new_event = (union perf_event *)aslr->event_copy;
|
|
|
|
aslr_machine = machines__findnew(&aslr->machines, machine->pid);
|
|
if (!aslr_machine)
|
|
return -ENOMEM;
|
|
if (aslr_tool__preload_kernel_maps(aslr_machine) < 0)
|
|
return -ENOMEM;
|
|
|
|
thread = machine__findnew_thread(aslr_machine, kernel_pid, 0);
|
|
if (!thread)
|
|
return -ENOMEM;
|
|
|
|
is_unregister = (event->ksymbol.flags & PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER);
|
|
|
|
memcpy(&new_event->ksymbol, &event->ksymbol, event->ksymbol.header.size);
|
|
|
|
if (is_unregister) {
|
|
new_event->ksymbol.addr = aslr_tool__findnew_mapping(aslr, machine, thread,
|
|
PERF_RECORD_MISC_KERNEL,
|
|
event->ksymbol.addr,
|
|
event->ksymbol.len,
|
|
/*pgoff=*/0);
|
|
err = perf_event__process_ksymbol(tool, event, sample, aslr_machine);
|
|
} else {
|
|
err = perf_event__process_ksymbol(tool, event, sample, aslr_machine);
|
|
new_event->ksymbol.addr = aslr_tool__findnew_mapping(aslr, machine, thread,
|
|
PERF_RECORD_MISC_KERNEL,
|
|
event->ksymbol.addr,
|
|
event->ksymbol.len,
|
|
/*pgoff=*/0);
|
|
}
|
|
if (err) {
|
|
thread__put(thread);
|
|
return err;
|
|
}
|
|
|
|
err = delegate->ksymbol(delegate, new_event, sample, machine);
|
|
thread__put(thread);
|
|
return err;
|
|
}
|
|
|
|
static int aslr_tool__process_sample(const struct perf_tool *tool,
|
|
union perf_event *event,
|
|
struct perf_sample *sample,
|
|
struct machine *machine)
|
|
{
|
|
struct evsel *evsel = sample->evsel;
|
|
struct delegate_tool *del_tool;
|
|
struct aslr_tool *aslr;
|
|
struct perf_tool *delegate;
|
|
int ret;
|
|
int orig_sample_size;
|
|
u64 sample_type;
|
|
struct thread *thread;
|
|
struct machine *aslr_machine;
|
|
__u64 max_i;
|
|
__u64 max_j;
|
|
union perf_event *new_event;
|
|
struct perf_sample new_sample;
|
|
__u64 *in_array, *out_array;
|
|
u8 cpumode;
|
|
u64 addr;
|
|
size_t i;
|
|
size_t j;
|
|
struct aslr_evsel_priv *priv = NULL;
|
|
u64 orig_sample_type;
|
|
u64 orig_regs_user;
|
|
u64 orig_regs_intr;
|
|
|
|
del_tool = container_of(tool, struct delegate_tool, tool);
|
|
aslr = container_of(del_tool, struct aslr_tool, tool);
|
|
delegate = aslr->tool.delegate;
|
|
|
|
if (evsel__is_dummy_event(evsel))
|
|
return delegate->sample(delegate, event, sample, machine);
|
|
|
|
ret = -EFAULT;
|
|
|
|
if (hashmap__find(&aslr->evsel_orig_attrs, evsel, &priv)) {
|
|
orig_sample_type = priv->orig_sample_type;
|
|
orig_regs_user = priv->orig_sample_regs_user;
|
|
orig_regs_intr = priv->orig_sample_regs_intr;
|
|
} else {
|
|
orig_sample_type = evsel->core.attr.sample_type;
|
|
orig_regs_user = evsel->core.attr.sample_regs_user;
|
|
orig_regs_intr = evsel->core.attr.sample_regs_intr;
|
|
}
|
|
|
|
orig_sample_size = evsel->sample_size;
|
|
|
|
sample_type = orig_sample_type;
|
|
sample_type &= ~PERF_SAMPLE_REGS_USER;
|
|
sample_type &= ~PERF_SAMPLE_REGS_INTR;
|
|
sample_type &= ASLR_SUPPORTED_SAMPLE_TYPE;
|
|
|
|
max_i = (event->header.size - sizeof(struct perf_event_header)) / sizeof(__u64);
|
|
max_j = (PERF_SAMPLE_MAX_SIZE - sizeof(struct perf_event_header)) / sizeof(__u64);
|
|
new_event = (union perf_event *)aslr->event_copy;
|
|
cpumode = sample->cpumode;
|
|
i = 0;
|
|
j = 0;
|
|
|
|
aslr_machine = machines__findnew(&aslr->machines, machine->pid);
|
|
if (!aslr_machine)
|
|
return -ENOMEM;
|
|
if (aslr_tool__preload_kernel_maps(aslr_machine) < 0)
|
|
return -ENOMEM;
|
|
|
|
thread = machine__findnew_thread(aslr_machine, sample->pid, sample->tid);
|
|
|
|
if (!thread)
|
|
return -ENOMEM;
|
|
|
|
if (max_i > PERF_SAMPLE_MAX_SIZE / sizeof(u64))
|
|
goto out_put;
|
|
|
|
new_event->sample.header = event->sample.header;
|
|
|
|
in_array = &event->sample.array[0];
|
|
out_array = &new_event->sample.array[0];
|
|
|
|
#define CHECK_BOUNDS(required_i, required_j) \
|
|
(i + (required_i) > max_i || j + (required_j) > max_j)
|
|
|
|
#define COPY_U64() \
|
|
do { \
|
|
if (CHECK_BOUNDS(1, 1)) { \
|
|
ret = -EFAULT; \
|
|
goto out_put; \
|
|
} \
|
|
out_array[j++] = in_array[i++]; \
|
|
} while (0)
|
|
|
|
#define REMAP_U64(addr_field) \
|
|
do { \
|
|
u64 remapped; \
|
|
if (CHECK_BOUNDS(1, 1)) { \
|
|
ret = -EFAULT; \
|
|
goto out_put; \
|
|
} \
|
|
remapped = aslr_tool__remap_address(aslr, thread, cpumode, addr_field); \
|
|
out_array[j++] = remapped; \
|
|
i++; \
|
|
} while (0)
|
|
|
|
if (orig_sample_type & PERF_SAMPLE_IDENTIFIER)
|
|
COPY_U64(); /* id */
|
|
if (orig_sample_type & PERF_SAMPLE_IP)
|
|
REMAP_U64(sample->ip);
|
|
if (orig_sample_type & PERF_SAMPLE_TID) {
|
|
union {
|
|
u64 val64;
|
|
u32 val32[2];
|
|
} u;
|
|
|
|
if (CHECK_BOUNDS(1, 1)) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
u.val32[0] = sample->pid;
|
|
u.val32[1] = sample->tid;
|
|
out_array[j++] = u.val64;
|
|
i++;
|
|
}
|
|
if (orig_sample_type & PERF_SAMPLE_TIME)
|
|
COPY_U64(); /* time */
|
|
if (orig_sample_type & PERF_SAMPLE_ADDR)
|
|
REMAP_U64(sample->addr);
|
|
if (orig_sample_type & PERF_SAMPLE_ID)
|
|
COPY_U64(); /* id */
|
|
if (orig_sample_type & PERF_SAMPLE_STREAM_ID)
|
|
COPY_U64(); /* stream_id */
|
|
if (orig_sample_type & PERF_SAMPLE_CPU)
|
|
COPY_U64(); /* cpu, res */
|
|
if (orig_sample_type & PERF_SAMPLE_PERIOD)
|
|
COPY_U64(); /* period */
|
|
if (orig_sample_type & PERF_SAMPLE_READ) {
|
|
if ((evsel->core.attr.read_format & PERF_FORMAT_GROUP) == 0) {
|
|
COPY_U64(); /* value */
|
|
if (evsel->core.attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
|
|
COPY_U64(); /* time_enabled */
|
|
if (evsel->core.attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
|
|
COPY_U64(); /* time_running */
|
|
if (evsel->core.attr.read_format & PERF_FORMAT_ID)
|
|
COPY_U64(); /* id */
|
|
if (evsel->core.attr.read_format & PERF_FORMAT_LOST)
|
|
COPY_U64(); /* lost */
|
|
} else {
|
|
u64 nr;
|
|
|
|
if (CHECK_BOUNDS(1, 1)) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
nr = in_array[i];
|
|
COPY_U64();
|
|
if (evsel->core.attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
|
|
COPY_U64(); /* time_enabled */
|
|
if (evsel->core.attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
|
|
COPY_U64(); /* time_running */
|
|
for (u64 cntr = 0; cntr < nr; cntr++) {
|
|
COPY_U64(); /* value */
|
|
if (evsel->core.attr.read_format & PERF_FORMAT_ID)
|
|
COPY_U64(); /* id */
|
|
if (evsel->core.attr.read_format & PERF_FORMAT_LOST)
|
|
COPY_U64(); /* lost */
|
|
}
|
|
}
|
|
}
|
|
if (orig_sample_type & PERF_SAMPLE_CALLCHAIN) {
|
|
u64 nr;
|
|
|
|
if (CHECK_BOUNDS(1, 1)) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
nr = in_array[i];
|
|
COPY_U64();
|
|
|
|
for (u64 cntr = 0; cntr < nr; cntr++) {
|
|
if (CHECK_BOUNDS(1, 1)) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
addr = in_array[i++];
|
|
if (addr >= PERF_CONTEXT_MAX) {
|
|
out_array[j++] = addr;
|
|
switch (addr) {
|
|
case PERF_CONTEXT_HV:
|
|
cpumode = PERF_RECORD_MISC_HYPERVISOR;
|
|
break;
|
|
case PERF_CONTEXT_KERNEL:
|
|
cpumode = PERF_RECORD_MISC_KERNEL;
|
|
break;
|
|
case PERF_CONTEXT_USER:
|
|
cpumode = PERF_RECORD_MISC_USER;
|
|
break;
|
|
case PERF_CONTEXT_GUEST:
|
|
cpumode = PERF_RECORD_MISC_GUEST_KERNEL;
|
|
break;
|
|
case PERF_CONTEXT_GUEST_KERNEL:
|
|
cpumode = PERF_RECORD_MISC_GUEST_KERNEL;
|
|
break;
|
|
case PERF_CONTEXT_GUEST_USER:
|
|
cpumode = PERF_RECORD_MISC_GUEST_USER;
|
|
break;
|
|
case PERF_CONTEXT_USER_DEFERRED:
|
|
if (cntr + 1 >= nr) {
|
|
pr_debug("Truncated callchain deferred cookie context\n");
|
|
ret = 0;
|
|
goto out_put;
|
|
}
|
|
/*
|
|
* Immediately followed by a 64-bit
|
|
* stitching cookie. Skip/Copy it!
|
|
*/
|
|
if (CHECK_BOUNDS(1, 1)) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
out_array[j++] = in_array[i++];
|
|
cntr++;
|
|
cpumode = PERF_RECORD_MISC_USER;
|
|
break;
|
|
default:
|
|
pr_debug("invalid callchain context: %"PRIx64"\n", addr);
|
|
ret = 0;
|
|
goto out_put;
|
|
}
|
|
continue;
|
|
}
|
|
addr = aslr_tool__remap_address(aslr, thread, cpumode, addr);
|
|
out_array[j++] = addr;
|
|
}
|
|
}
|
|
if (orig_sample_type & PERF_SAMPLE_RAW) {
|
|
size_t bytes = sizeof(u32) + sample->raw_size;
|
|
size_t u64_words = (bytes + 7) / 8;
|
|
|
|
if (i + u64_words > max_i || j + u64_words > max_j) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
memcpy(&out_array[j], &in_array[i], bytes);
|
|
i += u64_words;
|
|
j += u64_words;
|
|
/*
|
|
* TODO: certain raw samples can be remapped, such as
|
|
* tracepoints by examining their fields.
|
|
*/
|
|
pr_debug("Dropping raw samples as possible ASLR leak\n");
|
|
ret = 0;
|
|
goto out_put;
|
|
}
|
|
if (orig_sample_type & PERF_SAMPLE_BRANCH_STACK) {
|
|
u64 nr;
|
|
|
|
if (CHECK_BOUNDS(1, 1)) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
nr = in_array[i];
|
|
COPY_U64();
|
|
|
|
if (evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_HW_INDEX)
|
|
COPY_U64(); /* hw_idx */
|
|
|
|
if (nr > (ULLONG_MAX / 3)) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
if (nr * 3 > max_i - i || nr * 3 > max_j - j) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
for (u64 cntr = 0; cntr < nr; cntr++) {
|
|
u64 from = in_array[i++];
|
|
u64 to = in_array[i++];
|
|
|
|
from = aslr_tool__remap_address(aslr, thread, sample->cpumode, from);
|
|
to = aslr_tool__remap_address(aslr, thread, sample->cpumode, to);
|
|
|
|
out_array[j++] = from;
|
|
out_array[j++] = to;
|
|
out_array[j++] = in_array[i++]; /* flags */
|
|
}
|
|
if (evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS) {
|
|
if (nr > max_i - i || nr > max_j - j) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
for (u64 cntr = 0; cntr < nr; cntr++)
|
|
COPY_U64();
|
|
}
|
|
}
|
|
if (orig_sample_type & PERF_SAMPLE_REGS_USER) {
|
|
u64 abi;
|
|
|
|
if (CHECK_BOUNDS(1, 0)) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
abi = in_array[i++];
|
|
if (abi != PERF_SAMPLE_REGS_ABI_NONE) {
|
|
u64 nr = hweight64(orig_regs_user);
|
|
|
|
if (nr > max_i - i) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
i += nr;
|
|
}
|
|
}
|
|
if (orig_sample_type & PERF_SAMPLE_STACK_USER) {
|
|
u64 size;
|
|
|
|
if (CHECK_BOUNDS(1, 1)) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
size = in_array[i];
|
|
COPY_U64();
|
|
if (size > 0) {
|
|
size_t u64_words = size / 8 + (size % 8 ? 1 : 0);
|
|
|
|
if (u64_words > max_i - i || u64_words > max_j - j) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
memcpy(&out_array[j], &in_array[i], size);
|
|
if (size % 8) {
|
|
size_t pad = 8 - (size % 8);
|
|
|
|
memset(((char *)&out_array[j]) + size, 0, pad);
|
|
}
|
|
i += u64_words;
|
|
j += u64_words;
|
|
}
|
|
/* TODO: can this be less conservative? */
|
|
pr_debug("Dropping stack user sample as possible ASLR leak\n");
|
|
ret = 0;
|
|
goto out_put;
|
|
}
|
|
if (orig_sample_type & PERF_SAMPLE_WEIGHT_TYPE)
|
|
COPY_U64(); /* perf_sample_weight */
|
|
if (orig_sample_type & PERF_SAMPLE_DATA_SRC)
|
|
COPY_U64(); /* data_src */
|
|
if (orig_sample_type & PERF_SAMPLE_TRANSACTION)
|
|
COPY_U64(); /* transaction */
|
|
if (orig_sample_type & PERF_SAMPLE_REGS_INTR) {
|
|
u64 abi;
|
|
|
|
if (CHECK_BOUNDS(1, 0)) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
abi = in_array[i++];
|
|
if (abi != PERF_SAMPLE_REGS_ABI_NONE) {
|
|
u64 nr = hweight64(orig_regs_intr);
|
|
|
|
if (nr > max_i - i) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
i += nr;
|
|
}
|
|
}
|
|
if (orig_sample_type & PERF_SAMPLE_PHYS_ADDR) {
|
|
COPY_U64(); /* phys_addr */
|
|
/* TODO: can this be less conservative? */
|
|
pr_debug("Dropping physical address sample as possible ASLR leak\n");
|
|
ret = 0;
|
|
goto out_put;
|
|
}
|
|
if (orig_sample_type & PERF_SAMPLE_CGROUP)
|
|
COPY_U64(); /* cgroup */
|
|
if (orig_sample_type & PERF_SAMPLE_DATA_PAGE_SIZE)
|
|
COPY_U64(); /* data_page_size */
|
|
if (orig_sample_type & PERF_SAMPLE_CODE_PAGE_SIZE)
|
|
COPY_U64(); /* code_page_size */
|
|
|
|
if (orig_sample_type & PERF_SAMPLE_AUX) {
|
|
u64 size;
|
|
|
|
if (CHECK_BOUNDS(1, 1)) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
out_array[j] = in_array[i];
|
|
size = out_array[j++];
|
|
i++;
|
|
if (size > 0) {
|
|
size_t u64_words = size / 8 + (size % 8 ? 1 : 0);
|
|
|
|
if (u64_words > max_i - i || u64_words > max_j - j) {
|
|
ret = -EFAULT;
|
|
goto out_put;
|
|
}
|
|
memcpy(&out_array[j], &in_array[i], size);
|
|
if (size % 8) {
|
|
size_t pad = 8 - (size % 8);
|
|
|
|
memset(((char *)&out_array[j]) + size, 0, pad);
|
|
}
|
|
i += u64_words;
|
|
j += u64_words;
|
|
}
|
|
/* TODO: can this be less conservative? */
|
|
pr_debug("Dropping aux sample as possible ASLR leak\n");
|
|
ret = 0;
|
|
goto out_put;
|
|
}
|
|
|
|
if (evsel__is_offcpu_event(evsel)) {
|
|
/* TODO: can this be less conservative? */
|
|
pr_debug("Dropping off-CPU sample as possible ASLR leak\n");
|
|
ret = 0;
|
|
goto out_put;
|
|
}
|
|
|
|
new_event->sample.header.size = sizeof(struct perf_event_header) + j * sizeof(u64);
|
|
/* Temporarily override evsel attributes to match the stripped new_event format! */
|
|
evsel->sample_size = __evsel__sample_size(sample_type);
|
|
evsel->core.attr.sample_type = sample_type;
|
|
evsel->core.attr.sample_regs_user = 0;
|
|
evsel->core.attr.sample_regs_intr = 0;
|
|
perf_sample__init(&new_sample, /*all=*/ true);
|
|
ret = __evsel__parse_sample(evsel, new_event, &new_sample, /*needs_swap=*/false);
|
|
|
|
if (ret) {
|
|
/* Restore original attributes immediately if parsing fails */
|
|
evsel->sample_size = orig_sample_size;
|
|
evsel->core.attr.sample_type = orig_sample_type;
|
|
evsel->core.attr.sample_regs_user = orig_regs_user;
|
|
evsel->core.attr.sample_regs_intr = orig_regs_intr;
|
|
perf_sample__exit(&new_sample);
|
|
goto out_put;
|
|
}
|
|
|
|
new_sample.evsel = evsel;
|
|
ret = delegate->sample(delegate, new_event, &new_sample, machine);
|
|
perf_sample__exit(&new_sample);
|
|
|
|
/* Restore original attributes so trace ingestion never desynchronizes! */
|
|
evsel->sample_size = orig_sample_size;
|
|
evsel->core.attr.sample_type = orig_sample_type;
|
|
evsel->core.attr.sample_regs_user = orig_regs_user;
|
|
evsel->core.attr.sample_regs_intr = orig_regs_intr;
|
|
|
|
out_put:
|
|
thread__put(thread);
|
|
return ret;
|
|
}
|
|
|
|
#undef CHECK_BOUNDS
|
|
#undef COPY_U64
|
|
#undef REMAP_U64
|
|
|
|
static int skipn(int fd, off_t n)
|
|
{
|
|
char buf[4096];
|
|
ssize_t ret;
|
|
|
|
while (n > 0) {
|
|
ret = read(fd, buf, min_t(off_t, n, (off_t)sizeof(buf)));
|
|
if (ret <= 0)
|
|
return ret;
|
|
n -= ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static s64 aslr_tool__process_auxtrace(const struct perf_tool *tool __maybe_unused,
|
|
struct perf_session *session,
|
|
union perf_event *event)
|
|
{
|
|
pr_warning_once("ASLR: Dropping auxtrace data as it cannot be obfuscated.\n");
|
|
if (perf_data__is_pipe(session->data)) {
|
|
/* Copy behavior of the stub by reading all pipe data. */
|
|
int err = skipn(perf_data__fd(session->data), event->auxtrace.size);
|
|
|
|
if (err < 0)
|
|
return err;
|
|
}
|
|
return event->auxtrace.size;
|
|
}
|
|
|
|
static int aslr_tool__process_auxtrace_info(const struct perf_tool *tool __maybe_unused,
|
|
struct perf_session *session __maybe_unused,
|
|
union perf_event *event __maybe_unused)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static int aslr_tool__process_auxtrace_error(const struct perf_tool *tool __maybe_unused,
|
|
struct perf_session *session __maybe_unused,
|
|
union perf_event *event __maybe_unused)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
void aslr_tool__strip_attr_event(union perf_event *event, struct evlist *evlist)
|
|
{
|
|
u32 attr_size;
|
|
|
|
if (!evlist)
|
|
return;
|
|
|
|
attr_size = event->attr.attr.size ?: PERF_ATTR_SIZE_VER0;
|
|
|
|
if (attr_size >= (offsetof(struct perf_event_attr, sample_type) + sizeof(u64))) {
|
|
event->attr.attr.sample_type &= ASLR_SUPPORTED_SAMPLE_TYPE;
|
|
|
|
if (attr_size >= (offsetof(struct perf_event_attr, sample_regs_user) + sizeof(u64)))
|
|
event->attr.attr.sample_regs_user = 0;
|
|
if (attr_size >= (offsetof(struct perf_event_attr, sample_regs_intr) + sizeof(u64)))
|
|
event->attr.attr.sample_regs_intr = 0;
|
|
}
|
|
|
|
if (attr_size >= (offsetof(struct perf_event_attr, type) + sizeof(u32))) {
|
|
u32 type = event->attr.attr.type;
|
|
|
|
if (type == PERF_TYPE_BREAKPOINT &&
|
|
attr_size >= (offsetof(struct perf_event_attr, bp_addr) + sizeof(u64))) {
|
|
event->attr.attr.bp_addr = 0;
|
|
} else if (type >= PERF_TYPE_MAX) {
|
|
struct perf_pmu *pmu;
|
|
|
|
pmu = perf_pmus__find_by_type(type);
|
|
if (pmu && (!strcmp(pmu->name, "kprobe") ||
|
|
!strcmp(pmu->name, "uprobe"))) {
|
|
if (attr_size >= (offsetof(struct perf_event_attr, config1) + sizeof(u64)))
|
|
event->attr.attr.config1 = 0;
|
|
if (attr_size >= (offsetof(struct perf_event_attr, config2) + sizeof(u64)))
|
|
event->attr.attr.config2 = 0;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static int aslr_tool__init(struct aslr_tool *aslr, struct perf_tool *delegate)
|
|
{
|
|
delegate_tool__init(&aslr->tool, delegate);
|
|
aslr->tool.tool.ordered_events = true;
|
|
|
|
if (machines__init(&aslr->machines))
|
|
return -ENOMEM;
|
|
|
|
hashmap__init(&aslr->remap_addresses,
|
|
remap_addresses__hash, remap_addresses__equal,
|
|
/*ctx=*/NULL);
|
|
hashmap__init(&aslr->top_addresses,
|
|
top_addresses__hash, top_addresses__equal,
|
|
/*ctx=*/NULL);
|
|
hashmap__init(&aslr->evsel_orig_attrs,
|
|
evsel_hash, evsel_equal,
|
|
/*ctx=*/NULL);
|
|
|
|
aslr->tool.tool.sample = aslr_tool__process_sample;
|
|
/* read - reads a counter, okay to delegate. */
|
|
aslr->tool.tool.mmap = aslr_tool__process_mmap;
|
|
aslr->tool.tool.mmap2 = aslr_tool__process_mmap2;
|
|
aslr->tool.tool.comm = aslr_tool__process_comm;
|
|
aslr->tool.tool.fork = aslr_tool__process_fork;
|
|
aslr->tool.tool.exit = aslr_tool__process_exit;
|
|
/* namesspaces, cgroup, lost, lost_sample, aux, */
|
|
/* itrace_start, aux_output_hw_id, context_switch, throttle, unthrottle */
|
|
/* - no virtual addresses. */
|
|
aslr->tool.tool.ksymbol = aslr_tool__process_ksymbol;
|
|
/* bpf - no virtual address. */
|
|
aslr->tool.tool.text_poke = aslr_tool__process_text_poke;
|
|
/*
|
|
* event_update, tracing_data, finished_round, build_id, id_index,
|
|
* auxtrace_info, auxtrace_error, time_conv, thread_map, cpu_map,
|
|
* stat_config, stat, feature, finished_init, bpf_metadata, compressed,
|
|
* auxtrace - no virtual addresses.
|
|
*/
|
|
aslr->tool.tool.auxtrace = aslr_tool__process_auxtrace;
|
|
aslr->tool.tool.auxtrace_info = aslr_tool__process_auxtrace_info;
|
|
aslr->tool.tool.auxtrace_error = aslr_tool__process_auxtrace_error;
|
|
|
|
return 0;
|
|
}
|
|
|
|
struct perf_tool *aslr_tool__new(struct perf_tool *delegate)
|
|
{
|
|
struct aslr_tool *aslr = zalloc(sizeof(*aslr));
|
|
|
|
if (!aslr)
|
|
return NULL;
|
|
|
|
if (aslr_tool__init(aslr, delegate)) {
|
|
free(aslr);
|
|
return NULL;
|
|
}
|
|
return &aslr->tool.tool;
|
|
}
|
|
|
|
void aslr_tool__delete(struct perf_tool *tool)
|
|
{
|
|
struct delegate_tool *del_tool;
|
|
struct aslr_tool *aslr;
|
|
struct hashmap_entry *cur;
|
|
size_t bkt;
|
|
struct rb_node *nd;
|
|
|
|
if (!tool)
|
|
return;
|
|
|
|
del_tool = container_of(tool, struct delegate_tool, tool);
|
|
aslr = container_of(del_tool, struct aslr_tool, tool);
|
|
|
|
hashmap__for_each_entry(&aslr->remap_addresses, cur, bkt) {
|
|
struct remap_addresses_key *key = (struct remap_addresses_key *)cur->pkey;
|
|
|
|
if (key)
|
|
dso__put(key->dso);
|
|
zfree(&cur->pkey);
|
|
zfree(&cur->pvalue);
|
|
}
|
|
hashmap__for_each_entry(&aslr->top_addresses, cur, bkt) {
|
|
zfree(&cur->pkey);
|
|
zfree(&cur->pvalue);
|
|
}
|
|
hashmap__for_each_entry(&aslr->evsel_orig_attrs, cur, bkt) {
|
|
zfree(&cur->pvalue);
|
|
}
|
|
|
|
hashmap__clear(&aslr->remap_addresses);
|
|
hashmap__clear(&aslr->top_addresses);
|
|
hashmap__clear(&aslr->evsel_orig_attrs);
|
|
aslr_tool__destroy_machines_priv(&aslr->machines);
|
|
machines__destroy_kernel_maps(&aslr->machines);
|
|
|
|
while ((nd = rb_first_cached(&aslr->machines.guests)) != NULL) {
|
|
struct machine *machine = rb_entry(nd, struct machine, rb_node);
|
|
|
|
rb_erase_cached(nd, &aslr->machines.guests);
|
|
machine__delete(machine);
|
|
}
|
|
|
|
machines__exit(&aslr->machines);
|
|
free(aslr);
|
|
}
|
|
|
|
int aslr_tool__cache_orig_attrs(struct perf_tool *tool, struct evsel *evsel)
|
|
{
|
|
struct delegate_tool *del_tool = container_of(tool, struct delegate_tool, tool);
|
|
struct aslr_tool *aslr = container_of(del_tool, struct aslr_tool, tool);
|
|
struct aslr_evsel_priv *priv = zalloc(sizeof(*priv));
|
|
int err;
|
|
|
|
if (!priv)
|
|
return -ENOMEM;
|
|
|
|
priv->orig_sample_type = evsel->core.attr.sample_type;
|
|
priv->orig_sample_regs_user = evsel->core.attr.sample_regs_user;
|
|
priv->orig_sample_regs_intr = evsel->core.attr.sample_regs_intr;
|
|
priv->orig_sample_size = evsel->sample_size;
|
|
|
|
err = hashmap__add(&aslr->evsel_orig_attrs, evsel, priv);
|
|
if (err) {
|
|
free(priv);
|
|
return err;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void aslr_tool__strip_evlist(const struct perf_tool *tool __maybe_unused, struct evlist *evlist)
|
|
{
|
|
struct evsel *evsel;
|
|
|
|
evlist__for_each_entry(evlist, evsel) {
|
|
evsel->core.attr.sample_type &= ASLR_SUPPORTED_SAMPLE_TYPE;
|
|
evsel->core.attr.sample_regs_user = 0;
|
|
evsel->core.attr.sample_regs_intr = 0;
|
|
evsel->sample_size = __evsel__sample_size(evsel->core.attr.sample_type);
|
|
evsel__calc_id_pos(evsel);
|
|
|
|
if (evsel->core.attr.type == PERF_TYPE_BREAKPOINT) {
|
|
evsel->core.attr.bp_addr = 0;
|
|
} else if (evsel->core.attr.type >= PERF_TYPE_MAX) {
|
|
struct perf_pmu *pmu = perf_pmus__find_by_type(evsel->core.attr.type);
|
|
|
|
if (pmu && (!strcmp(pmu->name, "kprobe") ||
|
|
!strcmp(pmu->name, "uprobe"))) {
|
|
evsel->core.attr.config1 = 0;
|
|
evsel->core.attr.config2 = 0;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void aslr_tool__restore_evlist(const struct perf_tool *tool, struct evlist *evlist)
|
|
{
|
|
const struct delegate_tool *del_tool = container_of(tool, const struct delegate_tool, tool);
|
|
const struct aslr_tool *aslr = container_of(del_tool, const struct aslr_tool, tool);
|
|
struct evsel *evsel;
|
|
struct aslr_evsel_priv *priv;
|
|
|
|
evlist__for_each_entry(evlist, evsel) {
|
|
if (hashmap__find(&aslr->evsel_orig_attrs, evsel, &priv)) {
|
|
evsel->core.attr.sample_type = priv->orig_sample_type;
|
|
evsel->core.attr.sample_regs_user = priv->orig_sample_regs_user;
|
|
evsel->core.attr.sample_regs_intr = priv->orig_sample_regs_intr;
|
|
evsel->sample_size = priv->orig_sample_size;
|
|
evsel__calc_id_pos(evsel);
|
|
}
|
|
}
|
|
}
|