From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dl1-f74.google.com (mail-dl1-f74.google.com [74.125.82.74]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C465E374E42 for ; Fri, 5 Jun 2026 20:56:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780693016; cv=none; b=qvghd/cSZZdrPH24rPxtvSShF+nB/svBJhs56kUkLoJt4Q1KO94p7JNI8AKAeL+5d/JKf5A4sBXYTItav6Y5lEGGpPJGRO4JWcF/zqHlYQLq35lm+R/0WBDFwYM/K04LoCHysu4jhpfQIJ6DFCAndAQD6Bwu7J64KIiBxmcBy8I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780693016; c=relaxed/simple; bh=1KDedsWeVV197VLXtsYur8byb0Vfl2zoyZ9WALO003E=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=LrYUm8JAc6SUu9m3WHW/Q5NFBeYkWqLkU/4v+wHZ4Q2k1YakHtDciFmlw1tMsXk5/NWYhzfn8xSpDqshRq3X+7gSU7/PrqLA/Fz2CUP2PidmRFz4A3e6Z5Lom2OKMp/Ox3OtrnSt4lgI9cZ1C2xEK2w57c/3J4FMA8VKFjcPbFk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--irogers.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=n3Q3Hdrz; arc=none smtp.client-ip=74.125.82.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--irogers.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="n3Q3Hdrz" Received: by mail-dl1-f74.google.com with SMTP id a92af1059eb24-137f8f21861so3553397c88.0 for ; Fri, 05 Jun 2026 13:56:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1780693014; x=1781297814; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=De2XyD9fFC10ZREZubyNAz1vn0C0LivUJsJ59i36cQI=; b=n3Q3Hdrz+9DaAQ6UmEN5eunozW7+rojiNfvp76xlJbsvny1TLtzKi5zzB1hcZrCM2O gaVV0pcRAooyhMDtr1khQV++TO7qRN60m2mJb02Pz3XyZf+tNE7Us16lU/ZGCp7+Z8Tc QiGr9RyS1wQxH9M4+tMi6lKuSXxChFk8o04fzOK8XzccSxR+/7aDpMcop6V9nLC406yU W/RekG46u8a7zcMS3jJ4D2e1lod1E4agTzQoJlBoZD7Hn5liH0ezRzAp1r+YL7q/2pyA P47x6O39ppNAqID/iSxFO85Sr/ABkyqFEqWRjMs08p66t7wVLgXClZ2HlbK1UKJxg5ub cqbQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1780693014; x=1781297814; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=De2XyD9fFC10ZREZubyNAz1vn0C0LivUJsJ59i36cQI=; b=F7BeVKTfgDsAnsickUQ9Mno9CzmpQ0cPOqFGRjT6mEGkz1rj1RTZL69L4gmXWccfKM m/XN/icT9YBKPxajmpgBHsBkukOVcmk1X1NIXN39Rd1CTRTbTmHCqf2ZIyY/+ml9+cBU 2hIVBlSMgcCcZ5fl8jixnq2hlE3azMXiV/3SJriyFSE8UeC60q12J4EPO9ndxpPixXkt CrZAyZhyXeClArcllQk31xUPzuC9177CNYx7lSFHeBe8dSq/n8PvaSoMqgmdWpcsYazN 0yoygc5qhqINEle/vDkpkZrs37SGySBZSKU3vf3sKedob7xZRzMshoxE3JsOBMTWfFyi RyFA== X-Forwarded-Encrypted: i=1; AFNElJ8UpCjAABycGu/dLje3YBUH9h0xgmLaOJJJ9yb/XrSFfKWUR1nxm714ZoMWqu9v9UEi/pOZZdpHxqRY954=@vger.kernel.org X-Gm-Message-State: AOJu0Yxi9Sk2GdhcIjAgmAvAcusK1usb1uq3e8dmcBpnw+TMbrqA9FiS MKY0ZPDj8ZVMutjT2W5C9wGzKEI4xU060PXuw7H8gFNAbnp3D8MlIa8yJcIeC9CNR0rrzqfoiDF euOzW2Llg7Q== X-Received: from dlak14.prod.google.com ([2002:a05:701b:290e:b0:138:7f5:cf8b]) (user=irogers job=prod-delivery.src-stubby-dispatcher) by 2002:a05:7022:6b84:b0:137:f532:e345 with SMTP id a92af1059eb24-138067207c1mr2265865c88.26.1780693013540; Fri, 05 Jun 2026 13:56:53 -0700 (PDT) Date: Fri, 5 Jun 2026 13:56:44 -0700 In-Reply-To: <20260605194851.2533568-1-irogers@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260605194851.2533568-1-irogers@google.com> X-Mailer: git-send-email 2.54.0.1032.g2f8565e1d1-goog Message-ID: <20260605205649.2566948-1-irogers@google.com> Subject: [PATCH v14 0/5] perf tools: Add inject --aslr feature, early maps loading, and decoupling fixes From: Ian Rogers To: irogers@google.com, acme@kernel.org, namhyung@kernel.org Cc: adrian.hunter@intel.com, gmx@google.com, james.clark@linaro.org, jolsa@kernel.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, mingo@redhat.com, peterz@infradead.org Content-Type: text/plain; charset="UTF-8" This patch series introduces the new 'perf inject --aslr' feature to remap virtual memory addresses or drop physical memory event leaks when profile record data is shared between machines. Bundled with this feature is a bug fix inside the core map tracking tool that hardens perf session analysis against concurrent lookup data races. Detailed Mechanism of MMAP Mapping and ASLR virtual Address Allocation: The ASLR tool virtualizes the address space of the recorded processes by intercepting MMAP and MMAP2 events to build a consistent translation database, which is subsequently used to rewrite sample addresses. It maintains two primary lookup databases using hash maps: 1. 'remap_addresses': Maps an original mapping key to its new remapped base address. The key uses topological invariant coordinates: (machine, dso, invariant). The invariant is computed as (start - pgoff) for DSO-backed mappings. This invariant remains constant even when perf's internal overlap-resolution splits a VMA into fragmented pieces, ensuring split maps resolve consistently back to the same remapped base. 2. 'top_addresses': Tracks the allocation state per process (machine, pid). It maintains 'remapped_max' (the highest allocated address in the virtualized space) and 'orig_last_end' (the end address of the last processed original mapping). For each MMAP/MMAP2 event: - We look up the DSO and invariant key in 'remap_addresses'. If found, we reuse the translation, preserving the offset within the mapping. - If not found, we allocate a new remapped address space: - If the new mapping is contiguous to the previous one in the original address space (start == orig_last_end), we place it contiguously in the remapped space. This is critical to preserve the contiguity of mappings for downstream merging (e.g. symbols split by HugeTLB, or anonymous .bss segments adjacent to initialized data). - If not contiguous, we insert a 1-page gap (using page_size) from the previous maximum allocated address to prevent accidental merging of unrelated VMAs. - The event's start address (and pgoff for kernel maps) is rewritten, and the event is delegated to the output writer. To remain strictly conservative and guarantee security, the tool scrubs breakpoint addresses (bp_addr) from all synthesized stream headers, completely drops PERF_RECORD_TEXT_POKE events to prevent absolute immediate pointer operands leaks, and drops unsupported complex payloads (such as user register stacks, raw tracepoints, and hardware AUX tracing frames). Verification is reinforced with shell test ('inject_aslr.sh'). Prerequisite Bug Fix (Patch 1). During development, a core map indexing issue was identified and resolved to prevent concurrent lookup data races during session analysis. Changes since v13: - Patch 2: Added a NULL check for env before calling perf_env__kernel_is_64_bit(env) to prevent potential segfaults if the recorded environment has no headers. - Patch 5: Fixed sample_size and id_pos going out of sync during aslr_tool__strip_evlist() and aslr_tool__restore_evlist(). Instead of using evsel__reset_sample_bit(), which was acting as a no-op due to early bit clearing and corrupted sample_size, the tool now directly updates sample_type and recomputes sample_size/id_pos dynamically. Added orig_sample_size to aslr_evsel_priv to correctly restore the state. Changes since v12: - Patch 2: Fixed potential NULL pointer dereference in remap_addresses__hash() when handling unmapped memory events (key->dso is NULL) under REFCNT_CHECKING. - Patch 2: Dynamically detect machine architecture bitness via perf_env__kernel_is_64_bit() to select appropriate kernel_space_start boundaries, avoiding 64-bit address injection on 32-bit platforms. Changes since v11: - Patch 1: Fixed struct dso name accessor in maps.c by using dso__name() instead of ->name. - Patch 2: Fixed hash function in aslr.c to hash the underlying dso pointer using RC_CHK_ACCESS to support reference count checking. Changes since v10: - Patch 1: Added explicit tracking array logic in maps__load_maps() to correctly accumulate valid maps (skipping NULL entries after failures) and safely return the exact populated count, resolving out-of-bounds pointer iteration panics. - Patch 3: Fixed endianness bug during cross-endian sample parsing by passing evsel->needs_swap instead of false to __evsel__parse_sample in aslr.c, ensuring correct 32-bit field byte unswapping for packed fields. Refactored evsel__parse_sample to take a needs_swap argument via __evsel__parse_sample. - Patch 4: Fixed inject_aslr.sh exit code handling in trap functions to capture and propagate the correct pipeline failure status code instead of unconditionally returning success or failing the test. Changes since v9: - Patch 1: Added `-ENOMEM` error check inside `maps__find_symbol_by_name()` and return `NULL` early. Added map sorting state invalidation on early return in `maps__load_maps()`. - Patch 2: Fixed encapsulation by using `thread__maps()` and `thread__pid()` accessors in `aslr_tool__findnew_mapping()`. Added `pr_warning_once` warning when raw auxtrace data is dropped. - Patch 3: Fixed encapsulation by using `thread__maps()` and `thread__pid()` accessors in `aslr_tool__remap_address()`. Wrapped `evsel__parse_sample()` to temporarily disable `needs_swap` to avoid branch stack endianness corruption on cross-endian files. Fixed ISO C90 warning for declaration-after-statement for `orig_needs_swap`. - Patch 4: Fixed duplicate cleanup by explicitly removing trap handlers (`trap - EXIT TERM INT`) inside the `cleanup()` function. - Patch 5: Fixed heap corruption by adding size bounds checking before writing to `sample_regs_user` and `sample_regs_intr` fields. Added missing register mask clearing logic for the `itrace` synthesis path of `perf_event__repipe_attr()`. Ian Rogers (5): perf maps: Add maps__mutate_mapping perf inject/aslr: Add ASLR tool infrastructure and MMAP tracking perf inject/aslr: Implement sample address remapping perf test: Add inject ASLR test perf aslr: Strip sample registers tools/perf/builtin-inject.c | 79 +- tools/perf/tests/shell/inject_aslr.sh | 519 ++++++++++ tools/perf/util/Build | 1 + tools/perf/util/aslr.c | 1272 +++++++++++++++++++++++++ tools/perf/util/aslr.h | 41 + tools/perf/util/evsel.c | 6 +- tools/perf/util/evsel.h | 10 +- tools/perf/util/machine.c | 32 +- tools/perf/util/maps.c | 149 ++- tools/perf/util/maps.h | 3 + tools/perf/util/symbol-elf.c | 41 +- tools/perf/util/symbol.c | 17 +- 12 files changed, 2105 insertions(+), 65 deletions(-) create mode 100755 tools/perf/tests/shell/inject_aslr.sh create mode 100644 tools/perf/util/aslr.c create mode 100644 tools/perf/util/aslr.h -- 2.54.0.1032.g2f8565e1d1-goog