| //===-- options.inc ---------------------------------------------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef GWP_ASAN_OPTION |
| #error "Define GWP_ASAN_OPTION prior to including this file!" |
| #endif |
| |
| #ifndef GWP_ASAN_DEFAULT_ENABLED |
| #define GWP_ASAN_DEFAULT_ENABLED true |
| #endif |
| |
| #ifndef GWP_ASAN_STRINGIFY |
| #define GWP_ASAN_STRINGIFY(S) GWP_ASAN_STRINGIFY_(S) |
| #define GWP_ASAN_STRINGIFY_(S) #S |
| #endif |
| |
| GWP_ASAN_OPTION(bool, Enabled, GWP_ASAN_DEFAULT_ENABLED, |
| "Is GWP-ASan enabled? Defaults to " GWP_ASAN_STRINGIFY( |
| GWP_ASAN_DEFAULT_ENABLED) ".") |
| |
| GWP_ASAN_OPTION(int, MaxSimultaneousAllocations, 16, |
| "Number of simultaneously-guarded allocations available in the " |
| "pool. Defaults to 16.") |
| |
| GWP_ASAN_OPTION(int, SampleRate, 5000, |
| "The probability (1 / SampleRate) that an allocation is " |
| "selected for GWP-ASan sampling. Default is 5000. Sample rates " |
| "up to (2^30 - 1) are supported.") |
| |
| // Developer note - This option is not actually processed by GWP-ASan itself. It |
| // is included here so that a user can specify whether they want signal handlers |
| // or not. The supporting allocator should inspect this value to see whether |
| // signal handlers need to be installed, and then use |
| // crash_handler::installSignalHandlers() in order to install the handlers. Note |
| // that in order to support signal handlers, you will need to link against the |
| // optional crash_handler component. |
| GWP_ASAN_OPTION( |
| bool, InstallSignalHandlers, true, |
| "Install GWP-ASan signal handlers for SIGSEGV during dynamic loading. This " |
| "allows better error reports by providing stack traces for allocation and " |
| "deallocation when reporting a memory error. GWP-ASan's signal handler " |
| "will forward the signal to any previously-installed handler, and user " |
| "programs that install further signal handlers should make sure they do " |
| "the same. Note, if the previously installed SIGSEGV handler is SIG_IGN, " |
| "we terminate the process after dumping the error report.") |
| |
| GWP_ASAN_OPTION( |
| bool, Recoverable, false, |
| "Install GWP-ASan's signal handler in recoverable mode. This means that " |
| "upon GWP-ASan detecting an error, it'll print the error report, but *not* " |
| "crash. Only one crash per sampled allocation will ever be recorded, and " |
| "if a sampled allocation does actually cause a crash, it'll permanently " |
| "occupy a slot in the pool. The recoverable mode also means that " |
| "previously-installed signal handlers will only be triggered for " |
| "non-GWP-ASan errors, as all GWP-ASan errors won't be forwarded.") |
| |
| GWP_ASAN_OPTION(bool, InstallForkHandlers, true, |
| "Install GWP-ASan atfork handlers to acquire internal locks " |
| "before fork and release them after.") |
| |
| GWP_ASAN_OPTION(bool, help, false, "Print a summary of the available options.") |
| |
| // ============================================================================= |
| // ==== WARNING |
| // ============================================================================= |
| // If you are adding flags to GWP-ASan, please note that GWP-ASan flag strings |
| // may be parsed by trusted system components (on Android, GWP-ASan flag strings |
| // are parsed by libc during the dynamic loader). This means that GWP-ASan |
| // should never feature flags like log paths on disk, because this can lead to |
| // arbitrary file write and thus privilege escalation. For an example, see the |
| // setuid ASan log_path exploits: https://www.exploit-db.com/exploits/46241. |
| // |
| // Please place all new flags above this warning, so that the warning always |
| // stays at the bottom. |
