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* Update the file headers across all of the LLVM projects in the monorepoChandler Carruth2019-01-191-4/+3
| | | | | | | | | | | | | | | | | to reflect the new license. We understand that people may be surprised that we're moving the header entirely to discuss the new license. We checked this carefully with the Foundation's lawyer and we believe this is the correct approach. Essentially, all code in the project is now made available by the LLVM project under our new license, so you will see that the license headers include that license only. Some of our contributors have contributed code under our old license, and accordingly, we have retained a copy of our old license notice in the top-level files in each project and repository. llvm-svn: 351636
* [scudo] Add some logs for AndroidKostya Kortchinsky2018-07-061-0/+3
| | | | | | | | | | | | | | | | Summary: Namely, set the abort message, and allow to write the message to syslog if the option is enabled. Reviewers: alekseyshl Reviewed By: alekseyshl Subscribers: delcypher, #sanitizers, llvm-commits Differential Revision: https://reviews.llvm.org/D48902 llvm-svn: 336445
* [scudo] Read ARM feature bits using Fuchsia APIs.Kostya Kortchinsky2018-04-231-1/+12
| | | | | | | | | | | | | | | | | Summary: Fuchsia uses zx_system_get_features in lieu of getauxval. Use this call when checking for CRC32 support. Reviewers: cryptoad Reviewed By: cryptoad Subscribers: delcypher, llvm-commits, #sanitizers, kristof.beyls, chrib Differential Revision: https://reviews.llvm.org/D45896 llvm-svn: 330598
* [scudo] Make logging more consistentKostya Kortchinsky2018-03-071-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: A few changes related to logging: - prepend `Scudo` to the error messages so that users can identify that we reported an error; - replace a couple of `Report` calls in the RSS check code with `dieWithMessage`/`Print`, mark a condition as `UNLIKELY` in the process; - change some messages so that they all look more or less the same. This includes the `CHECK` message; - adapt a couple of tests with the new strings. A couple of side notes: this results in a few 1-line-blocks, for which I left brackets. There doesn't seem to be any style guide for that, I can remove them if need be. I didn't use `SanitizerToolName` in the strings, but directly `Scudo` because we are the only users, I could change that too. Reviewers: alekseyshl, flowerhack Reviewed By: alekseyshl Subscribers: mgorny, delcypher, llvm-commits, #sanitizers Differential Revision: https://reviews.llvm.org/D44171 llvm-svn: 326901
* [scudo] Workaround for uninitialized Bionic globalsKostya Kortchinsky2017-11-271-1/+11
| | | | | | | | | | | | | | | | | | | Summary: Bionic doesn't initialize its globals early enough. This causes issues when trying to access them from a preinit_array (b/25751302) or from another constructor called before the libc one (b/68046352). __progname is initialized after the other globals, so we can check its value to know if calling `getauxval` is safe. Reviewers: alekseyshl Reviewed By: alekseyshl Subscribers: srhines, llvm-commits Differential Revision: https://reviews.llvm.org/D40504 llvm-svn: 319099
* [scudo] Overhaul hardware CRC32 feature detectionKostya Kortchinsky2017-11-221-94/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This patch aims at condensing the hardware CRC32 feature detection and making it slightly more effective on Android. The following changes are included: - remove the `CPUFeature` enum, and get rid of one level of nesting of functions: we only used CRC32, so we just implement and use `hasHardwareCRC32`; - allow for a weak `getauxval`: the Android toolchain is compiled at API level 14 for Android ARM, meaning no `getauxval` at compile time, yet we will run on API level 27+ devices. The `/proc/self/auxv` fallback can work but is worthless for a process like `init` where the proc filesystem doesn't exist yet. If a weak `getauxval` doesn't exist, then fallback. - couple of extra corrections. Reviewers: alekseyshl Reviewed By: alekseyshl Subscribers: kubamracek, aemerson, srhines, kristof.beyls, llvm-commits Differential Revision: https://reviews.llvm.org/D40322 llvm-svn: 318859
* [scudo] Bump the Android API level requirement to 21 for getauxvalKostya Kortchinsky2017-11-101-3/+3
| | | | | | | | | | | | | | | | | | | | Summary: `getauxval` was introduced in 18 & 21 depending on the architecture. Bump the requirement to 21. It also turns out that the NDK is finicky: NDK r13b doesn't include sys/auxv.h when creating a standalone toolchain at API level 19 for ARM. So 18 didn't work well with older NDKs. Reviewers: alekseyshl Reviewed By: alekseyshl Subscribers: aemerson, srhines, llvm-commits, kristof.beyls Differential Revision: https://reviews.llvm.org/D39905 llvm-svn: 317907
* [sanitizer] Add Scudo to the sanitizer lint checks.Kostya Kortchinsky2017-11-081-4/+2
| | | | | | | | | | | | | | | | | | | | Summary: Scudo abides by the coding style enforced by the sanitizer_common linter, but as of right now, it's not linter-enforced. Add Scudo to the list of directories checked by check_lint.sh. Also: fixes some linter errors found after getting this running. Reviewers: cryptoad Reviewed By: cryptoad Subscribers: llvm-commits, kubamracek Differential Revision: https://reviews.llvm.org/D39757 llvm-svn: 317699
* [scudo] Do not include sanitizer_posix.h if not on a Posix platformKostya Kortchinsky2017-10-161-2/+2
| | | | | | | | | | | | | | | | Summary: Move the `sanitizer_posix.h` include within the `SANITIZER_ANDROID` `#if`, otherwise this errors when built on non-Posix platforms (eg: Fuchsia). Reviewers: alekseyshl Reviewed By: alekseyshl Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D38956 llvm-svn: 315917
* [scudo] getauxval alternative for AndroidKostya Kortchinsky2017-09-061-12/+44
| | | | | | | | | | | | | | | | | | Summary: `getauxval` was introduced with API level 18. In order to get things to work at lower API levels (for the toolchain itself which is built at 14 for 32-bit), we introduce an alternative implementation reading directly from `/proc/self/auxv`. Reviewers: alekseyshl Reviewed By: alekseyshl Subscribers: srhines, llvm-commits Differential Revision: https://reviews.llvm.org/D37488 llvm-svn: 312653
* [scudo] PRNG makeoverKostya Kortchinsky2017-07-121-36/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This follows the addition of `GetRandom` with D34412. We remove our `/dev/urandom` code and use the new function. Additionally, change the PRNG for a slightly faster version. One of the issues with the old code is that we have 64 full bits of randomness per "next", using only 8 of those for the Salt and discarding the rest. So we add a cached u64 in the PRNG that can serve up to 8 u8 before having to call the "next" function again. During some integration work, I also realized that some very early processes (like `init`) do not benefit from `/dev/urandom` yet. So if there is no `getrandom` syscall as well, we have to fallback to some sort of initialization of the PRNG. Now a few words on why XoRoShiRo and not something else. I have played a while with various PRNGs on 32 & 64 bit platforms. Some results are below. LCG 32 & 64 are usually faster but produce respectively 15 & 31 bits of entropy, meaning that to get a full 64-bit, you would need to call them several times. The simple XorShift is fast, produces 32 bits but is mediocre with regard to PRNG test suites, PCG is slower overall, and XoRoShiRo is faster than XorShift128+ and produces full 64 bits. %%% root@tulip-chiphd:/data # ./randtest.arm [+] starting xs32... [?] xs32 duration: 22431833053ns [+] starting lcg32... [?] lcg32 duration: 14941402090ns [+] starting pcg32... [?] pcg32 duration: 44941973771ns [+] starting xs128p... [?] xs128p duration: 48889786981ns [+] starting lcg64... [?] lcg64 duration: 33831042391ns [+] starting xos128p... [?] xos128p duration: 44850878605ns root@tulip-chiphd:/data # ./randtest.aarch64 [+] starting xs32... [?] xs32 duration: 22425151678ns [+] starting lcg32... [?] lcg32 duration: 14954255257ns [+] starting pcg32... [?] pcg32 duration: 37346265726ns [+] starting xs128p... [?] xs128p duration: 22523807219ns [+] starting lcg64... [?] lcg64 duration: 26141304679ns [+] starting xos128p... [?] xos128p duration: 14937033215ns %%% Reviewers: alekseyshl Reviewed By: alekseyshl Subscribers: aemerson, kristof.beyls, llvm-commits Differential Revision: https://reviews.llvm.org/D35221 llvm-svn: 307798
* [scudo] Move thread local variables into their own filesKostya Kortchinsky2017-04-271-2/+2
| | | | | | | | | | | | | | | | | | | Summary: This change introduces scudo_tls.h & scudo_tls_linux.cpp, where we move the thread local variables used by the allocator, namely the cache, quarantine cache & prng. `ScudoThreadContext` will hold those. This patch doesn't introduce any new platform support yet, this will be the object of a later patch. This also changes the PRNG so that the structure can be POD. Reviewers: kcc, dvyukov, alekseyshl Reviewed By: dvyukov, alekseyshl Subscribers: llvm-commits, mgorny Differential Revision: https://reviews.llvm.org/D32440 llvm-svn: 301584
* [scudo] Minor changes and refactoringKostya Kortchinsky2017-04-201-54/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This is part of D31947 that is being split into several smaller changes. This one deals with all the minor changes, more specifically: - Rename some variables and functions to make their purpose clearer; - Reorder some code; - Mark the hot termination incurring checks as `UNLIKELY`; if they happen, the program will die anyway; - Add a `getScudoChunk` method; - Add an `eraseHeader` method to ScudoChunk that will clear a header with 0s; - Add a parameter to `allocate` to know if the allocated chunk should be filled with zeros. This allows `calloc` to not have to call `GetActuallyAllocatedSize`; more changes to get rid of this function on the hot paths will follow; - reallocate was missing a check to verify that the pointer is properly aligned on `MinAlignment`; - The `Stats` in the secondary have to be protected by a mutex as the `Add` and `Sub` methods are actually not atomic; - The software CRC32 function was moved to the header to allow for inlining. Reviewers: dvyukov, alekseyshl, kcc Reviewed By: dvyukov Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D32242 llvm-svn: 300846
* [scudo] Refactor of CRC32 and ARM runtime CRC32 detectionKostya Kortchinsky2017-01-181-3/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | Summary: ARM & AArch64 runtime detection for hardware support of CRC32 has been added via check of the AT_HWVAL auxiliary vector. Following Michal's suggestions in D28417, the CRC32 code has been further changed and looks better now. When compiled with full relro (which is strongly suggested to benefit from additional hardening), the weak symbol for computeHardwareCRC32 is read-only and the assembly generated is fairly clean and straight forward. As suggested, an additional optimization is to skip the runtime check if SSE 4.2 has been enabled globally, as opposed to only for scudo_crc32.cpp. scudo_crc32.h has no purpose anymore and was removed. Reviewers: alekseyshl, kcc, rengolin, mgorny, phosek Reviewed By: rengolin, mgorny Subscribers: aemerson, rengolin, llvm-commits Differential Revision: https://reviews.llvm.org/D28574 llvm-svn: 292409
* [scudo] Eliminate the runtime dependency on libc++abiPetr Hosek2017-01-171-1/+1
| | | | | | | | | | | | Making this variable non-static avoids the need for locking to ensure that the initialization is thread-safe which in turns eliminates the runtime dependency on libc++abi library (for __cxa_guard_acquire and __cxa_guard_release) which makes it possible to link scudo against pure C programs. Differential Revision: https://reviews.llvm.org/D28757 llvm-svn: 292253
* [scudo] Separate hardware CRC32 routinesKostya Kortchinsky2017-01-101-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Summary: As raised in D28304, enabling SSE 4.2 for the whole Scudo tree leads to the emission of SSE 4.2 instructions everywhere, while the runtime checks only applied to the CRC32 computing function. This patch separates the CRC32 function taking advantage of the hardware into its own file, and only enabled -msse4.2 for that file, if detected to be supported by the compiler. Another consequence of removing SSE4.2 globally is realizing that memcpy were not being optimized, which turned out to be due to the -fno-builtin in SANITIZER_COMMON_CFLAGS. So we now explicitely enable builtins for Scudo. The resulting assembly looks good, with some CALLs are introduced instead of the CRC32 code being inlined. Reviewers: kcc, mgorny, alekseyshl Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D28417 llvm-svn: 291570
* [sanitizer] Do not use the alignment-rounded-up size when using the secondaryKostya Kortchinsky2016-12-081-1/+3
| | | | | | | | | | | | | | | | | | Summary: The combined allocator rounds up the requested size with regard to the alignment, which makes sense when being serviced by the primary as it comes with alignment guarantees, but not with the secondary. For the rare case of large alignments, it wastes memory, and entices unnecessarily large fields for the Scudo header. With this patch, we pass the non-alignement-rounded-up size to the secondary, and adapt the Scudo code for this change. Reviewers: alekseyshl, kcc Subscribers: llvm-commits, kubabrecka Differential Revision: https://reviews.llvm.org/D27428 llvm-svn: 289088
* [scudo] 32-bit and hardware agnostic supportKostya Kortchinsky2016-11-301-44/+106
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: This update introduces i386 support for the Scudo Hardened Allocator, and offers software alternatives for functions that used to require hardware specific instruction sets. This should make porting to new architectures easier. Among the changes: - The chunk header has been changed to accomodate the size limitations encountered on 32-bit architectures. We now fit everything in 64-bit. This was achieved by storing the amount of unused bytes in an allocation rather than the size itself, as one can be deduced from the other with the help of the GetActuallyAllocatedSize function. As it turns out, this header can be used for both 64 and 32 bit, and as such we dropped the requirement for the 128-bit compare and exchange instruction support (cmpxchg16b). - Add 32-bit support for the checksum and the PRNG functions: if the SSE 4.2 instruction set is supported, use the 32-bit CRC32 instruction, and in the XorShift128, use a 32-bit based state instead of 64-bit. - Add software support for CRC32: if SSE 4.2 is not supported, fallback on a software implementation. - Modify tests that were not 32-bit compliant, and expand them to cover more allocation and alignment sizes. The random shuffle test has been deactivated for linux-i386 & linux-i686 as the 32-bit sanitizer allocator doesn't currently randomize chunks. Reviewers: alekseyshl, kcc Subscribers: filcab, llvm-commits, tberghammer, danalbert, srhines, mgorny, modocache Differential Revision: https://reviews.llvm.org/D26358 llvm-svn: 288255
* [scudo] Fix an edge case in the secondary allocatorKostya Kortchinsky2016-09-301-2/+2
| | | | | | | | | | | | | | | Summary: s/CHECK_LT/CHECK_LE/ in the secondary allocator, as under certain circumstances Ptr + Size can be equal to MapEnd. This edge case was not found by the current tests, so those were extended to be able to catch that. Reviewers: kcc Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D25101 llvm-svn: 282913
* [sanitizer] Implement a __asan_default_options() equivalent for ScudoKostya Serebryany2016-08-021-1/+1
| | | | | | | | | | | | | | Summary: Currently, the Scudo Hardened Allocator only gets its flags via the SCUDO_OPTIONS environment variable. With this patch, we offer the opportunity for programs to define their own options via __scudo_default_options() which behaves like __asan_default_options() (weak symbol). A relevant test has been added as well, and the documentation updated accordingly. I also used this patch as an opportunity to rename a few variables to comply with the LLVM naming scheme, and replaced a use of Report with dieWithMessage for consistency (and to avoid a callback). Reviewers: llvm-commits, kcc Differential Revision: https://reviews.llvm.org/D23018 llvm-svn: 277536
* [sanitizer] Initial implementation of a Hardened AllocatorKostya Serebryany2016-06-071-0/+133
Summary: This is an initial implementation of a Hardened Allocator based on Sanitizer Common's CombinedAllocator. It aims at mitigating heap based vulnerabilities by adding several features to the base allocator, while staying relatively fast. The following were implemented: - additional consistency checks on the allocation function parameters and on the heap chunks; - use of checksum protected chunk header, to detect corruption; - randomness to the allocator base; - delayed freelist (quarantine), to mitigate use after free and overall determinism. Additional mitigations are in the works. Reviewers: eugenis, aizatsky, pcc, krasin, vitalybuka, glider, dvyukov, kcc Subscribers: kubabrecka, filcab, llvm-commits Differential Revision: http://reviews.llvm.org/D20084 llvm-svn: 271968
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