Fixes the ASan RISC-V memory mapping (originally introduced by D87580 and
D87581). This should be an improvement both in terms of first principles
soundness and observed test failures --- test failures would occur
non-deterministically depending on the ASLR random offset.
On RISC-V Linux (64-bit), `TASK_UNMAPPED_BASE` is currently defined as
`PAGE_ALIGN(TASK_SIZE / 3)`. The non-power-of-two divisor makes the result
be the not very round number 0x1555556000. That address had to be further
rounded to ensure page alignment after the shadow scale shifting is applied.
Still, that value explains why the mapping table may look less regular than
expected.
Further cleanups:
- Moved the mapping table comment, to ensure that the two Linux/AArch64
tables stayed together;
- Removed mention of Sv48. Neither the original mapping nor this one are
compatible with an actual Linux Sv48 address space (mainline Linux still
operates Sv48 in Sv39 mode). A future patch can improve this;
- Removed the additional comments, for consistency.
Differential Revision: https://reviews.llvm.org/D97646
This is needed because macOS on Apple Silicon has some reserved pages inside the "regular" shadow memory location, and mapping over that location fails.
Differential Revision: https://reviews.llvm.org/D82912
Summary:
This refactors some common support related to shadow memory setup from
asan and hwasan into sanitizer_common. This should not only reduce code
duplication but also make these facilities available for new compiler-rt
uses (e.g. heap profiling).
In most cases the separate copies of the code were either identical, or
at least functionally identical. A few notes:
In ProtectGap, the asan version checked the address against an upper
bound (kZeroBaseMaxShadowStart, which is (2^18). I have created a copy
of kZeroBaseMaxShadowStart in hwasan_mapping.h, with the same value, as
it isn't clear why that code should not do the same check. If it
shouldn't, I can remove this and guard this check so that it only
happens for asan.
In asan's InitializeShadowMemory, in the dynamic shadow case it was
setting __asan_shadow_memory_dynamic_address to 0 (which then sets both
macro SHADOW_OFFSET as well as macro kLowShadowBeg to 0) before calling
FindDynamicShadowStart(). AFAICT this is only needed because
FindDynamicShadowStart utilizes kHighShadowEnd to
get the shadow size, and kHighShadowEnd is a macro invoking
MEM_TO_SHADOW(kHighMemEnd) which in turn invokes:
(((kHighMemEnd) >> SHADOW_SCALE) + (SHADOW_OFFSET))
I.e. it computes the shadow space needed by kHighMemEnd (the shift), and
adds the offset. Since we only want the shadow space here, the earlier
setting of SHADOW_OFFSET to 0 via __asan_shadow_memory_dynamic_address
accomplishes this. In the hwasan version, it simply gets the shadow
space via "MemToShadowSize(kHighMemEnd)", where MemToShadowSize just
does the shift. I've simplified the asan handling to do the same
thing, and therefore was able to remove the setting of the SHADOW_OFFSET
via __asan_shadow_memory_dynamic_address to 0.
Reviewers: vitalybuka, kcc, eugenis
Subscribers: dberris, #sanitizers, llvm-commits, davidxl
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D83247
The VM layout on iOS is not stable between releases. On 64-bit iOS and
its derivatives we use a dynamic shadow offset that enables ASan to
search for a valid location for the shadow heap on process launch rather
than hardcode it.
This commit extends that approach for 32-bit iOS plus derivatives and
their simulators.
rdar://50645192
rdar://51200372
rdar://51767702
Reviewed By: delcypher
Differential Revision: https://reviews.llvm.org/D63586
llvm-svn: 364105
Summary:
This patch contains the bits required to make the AddressSanitizer work on SPARC64/Linux (SPARC-T4 and later).
Patch by Eric Botcazou.
Reviewers: #sanitizers, vitalybuka, krytarowski
Reviewed By: #sanitizers, vitalybuka
Subscribers: brad, vitalybuka, ro, jyknight, kubamracek, fedor.sergeev, jdoerfert, llvm-commits, #sanitizers
Tags: #sanitizers, #llvm
Differential Revision: https://reviews.llvm.org/D58434
llvm-svn: 355980
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
This is not needed after we've forked the Myriad version. Not to
mention it produces a compiler warning.
Differential Revision: https://reviews.llvm.org/D47054
llvm-svn: 332744
The Myriad RTEMS memory system has a few unique aspects that
require support in the ASan run-time.
- A limited amount of memory (currently 512M).
- No virtual memory, no memory protection.
- DRAM starts at address 0x80000000. Other parts of memory may be
used for MMIO, etc.
- The second highest address bit is the "cache" bit, and 0x80000000
and 0x84000000 alias to the same memory.
To support the above, we make the following changes:
- Use a ShadowScale of 5, to reduce shadow memory overhead.
- Adjust some existing macros to remove assumption that the lowest
memory address is 0.
- add a RawAddr macro that on Myriad strips the cache bit from the
input address, before using the address for shadow memory (for other
archs this does nothing).
- We must check that an address is in DRAM range before using it to
index into shadow memory.
Differential Revision: https://reviews.llvm.org/D46456
llvm-svn: 332690
This appears to be a copy/paste artifact from `AddrIsInHighMem`. It was caught by Firefox's jit-tests on Win64.
Differential Revision: https://reviews.llvm.org/D46291
llvm-svn: 332092
In more recent Linux kernels with 47 bit VMAs the layout of virtual memory
for powerpc64 changed causing the address sanitizer to not work properly. This
patch adds support for 47 bit VMA kernels for powerpc64 and fixes up test
cases.
https://reviews.llvm.org/D40908
There is an associated patch for trunk.
Tested on several 4.x and 3.x kernel releases.
llvm-svn: 320110
Summary:
This change reverts r318575 and changes FindDynamicShadowStart() to
keep the memory range it found mapped PROT_NONE to make sure it is
not reused. We also skip MemoryRangeIsAvailable() check, because it
is (a) unnecessary, and (b) would fail anyway.
Reviewers: pcc, vitalybuka, kcc
Subscribers: srhines, kubamracek, mgorny, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D40203
llvm-svn: 318666
Revert the following commits:
r318369 [asan] Fallback to non-ifunc dynamic shadow on android<22.
r318235 [asan] Prevent rematerialization of &__asan_shadow.
r317948 [sanitizer] Remove unnecessary attribute hidden.
r317943 [asan] Use dynamic shadow on 32-bit Android.
MemoryRangeIsAvailable() reads /proc/$PID/maps into an mmap-ed buffer
that may overlap with the address range that we plan to use for the
dynamic shadow mapping. This is causing random startup crashes.
llvm-svn: 318575
The requirement is that shadow memory must be aligned to page
boundaries (4k in this case). Use a closed form equation that always
satisfies this requirement.
Differential Revision: https://reviews.llvm.org/D39471
llvm-svn: 318421
Allow user to override shadow scale in compiler_rt by passing
-DCOMPILER_RT_ASAN_SHADOW_SCALE=n to CMake. Propagate the override
shadow scale value via a compiler define to compiler-rt and asan
tests. Tests will use the define to partially disable unsupported
tests. Set "-mllvm -asan-mapping-scale=<n>" for compiler_rt tests.
Differential Revision: https://reviews.llvm.org/D39469
llvm-svn: 318038
Summary:
The following kernel change has moved ET_DYN base to 0x4000000 on arm32:
https://marc.info/?l=linux-kernel&m=149825162606848&w=2
Switch to dynamic shadow base to avoid such conflicts in the future.
Reserve shadow memory in an ifunc resolver, but don't use it in the instrumentation
until PR35221 is fixed. This will eventually let use save one load per function.
Reviewers: kcc
Subscribers: aemerson, srhines, kubamracek, kristof.beyls, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D39393
llvm-svn: 317943
The VM layout is not stable between iOS version releases, so switch to dynamic shadow offset.
Differential Revision: https://reviews.llvm.org/D25218
llvm-svn: 283375
The VM layout is not stable between iOS version releases, so switch to dynamic shadow offset.
Differential Revision: https://reviews.llvm.org/D25218
llvm-svn: 283240
Summary:
This patch is adding support for dynamic shadow allocation.
This is a merge and re-commit of the following patches.
```
[compiler-rt] Fix Asan build on Android
https://reviews.llvm.org/D24768
[compiler-rt] Add support for the dynamic shadow allocation
https://reviews.llvm.org/D23363
```
This patch needed to re-land at the same time:
```
[asan] Support dynamic shadow address instrumentation
https://reviews.llvm.org/D23354
```
Reviewers: rnk, zaks.anna
Subscribers: tberghammer, danalbert, kubabrecka, dberris, chrisha, llvm-commits
Differential Revision: https://reviews.llvm.org/D25104
llvm-svn: 282882
Summary:
The dynamic shadow code is not detected correctly on Android.
The android shadow seems to start at address zero.
The bug is introduced here:
https://reviews.llvm.org/D23363
Started here: https://build.chromium.org/p/chromium.fyi/builders/ClangToTAndroidASan/builds/4029
Likely due to an asan runtime change, filed https://llvm.org/bugs/show_bug.cgi?id=30462
From asan_mapping.h:
```
#if SANITIZER_WORDSIZE == 32
# if SANITIZER_ANDROID
# define SHADOW_OFFSET (0) <<---- HERE
# elif defined(__mips__)
```
Shadow address on android is 0.
From asan_rtl.c:
```
if (shadow_start == 0) {
[...]
shadow_start = FindAvailableMemoryRange(space_size, alignment, granularity);
}
```
We assumed that 0 is dynamic address.
On windows, the address was determined with:
```
# elif SANITIZER_WINDOWS64
# define SHADOW_OFFSET __asan_shadow_memory_dynamic_address
# else
```
and __asan_shadow_memory_dynamic_address is initially zero.
Reviewers: rnk, eugenis, vitalybuka
Subscribers: kcc, tberghammer, danalbert, kubabrecka, dberris, llvm-commits, chrisha
Differential Revision: https://reviews.llvm.org/D24768
llvm-svn: 282085
Summary:
This patch is adding the needed code to compiler-rt to support
dynamic shadow.
This is to support this patch:
https://reviews.llvm.org/D23354
It's adding support for using a shadow placed at a dynamic address determined
at runtime.
The dynamic shadow is required to work on windows 64-bits.
Reviewers: rnk, kcc, vitalybuka
Subscribers: kubabrecka, dberris, llvm-commits, chrisha
Differential Revision: https://reviews.llvm.org/D23363
llvm-svn: 281909
This is part of the effort for asan to support Windows 64 bit.
Patch by Wei Wang
Differential Revision: http://reviews.llvm.org/D21525
llvm-svn: 273270
This patch makes ASAN for aarch64 use the same shadow offset for all
currently supported VMAs (39 and 42 bits). The shadow offset is the
same for 39-bit (36).
llvm-svn: 252497
This patch adds support for asan on aarch64-linux with 42-bit VMA
(current default config for 64K pagesize kernels). The support is
enabled by defining the SANITIZER_AARCH64_VMA to 42 at build time
for both clang/llvm and compiler-rt. The default VMA is 39 bits.
For 42-bit VMA aarch64 uses SANITIZIER_CAN_USER_ALLOCATOR64.
llvm-svn: 245596
The number of unaccessible pages at the beginning of the address
space can differ between processes on the same machine. Try different
values at runtime to protect as much memory as possible.
llvm-svn: 244364
This patch enables asan for aarch64/linux. It marks it as 'unstable-release',
since some tests are failing due either kernel missing support of non-executable
pages in mmap or environment instability (infinite loop in juno reference
boards).
It sets decorate_proc_maps test to require stable-release, since the test expects
the shadow memory to not be executable and the support for aarch64 is only
added recently by Linux (da141706aea52c1a9 - 4.0).
It also XFAIL static_tls test for aarch64 linker may omit the __tls_get_addr call
as a TLS optimization.
llvm-svn: 244054
ASan shadow on Android starts at address 0 for both historic and
performance reasons. This is possible because the platform mandates
-pie, which makes lower memory region always available.
This is not such a good idea on 64-bit platforms because of MAP_32BIT
incompatibility.
This patch changes Android/AArch64 mapping to be the same as that of
Linux/AAarch64.
llvm-svn: 243548
Summary:
This is one of many changes needed for compiler-rt to get it building on iOS.
This change ifdefs out headers and functionality that aren't available on iOS, and adds support for iOS and the iOS simulator to as an.
Note: this change does not enable building for iOS, as there are more changes to come.
Reviewers: glider, kubabrecka, bogner, samsonov
Reviewed By: samsonov
Subscribers: samsonov, zaks.anna, llvm-commits
Differential Revision: http://reviews.llvm.org/D10515
llvm-svn: 240469
for both PPC64 Big and Little endian modes, so also eliminates the need for
the BIG_ENDIAN/LITTLE_ENDIAN #ifdeffery.
By trial and error, it also looks like the kPPC64_ShadowOffset64 value is
valid using (1ULL << 41) for both BE and LE, so that #if/#elif/#endif block
has also been simplified.
Differential Revision: http://reviews.llvm.org/D6044
llvm-svn: 221457
Vitaly Buka