Allowing overriding the default ASAN shadow mapping offset with the
-asan-shadow-offset option, and allow zero to be specified for both offset and
scale.
Patch by Aaron Carroll <aaronc@apple.com>.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268724 91177308-0d34-0410-b5e6-96231b3b80d8
Allowing overriding the default ASAN shadow mapping offset with the
-asan-shadow-offset option, and allow zero to be specified for both offset and
scale.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268586 91177308-0d34-0410-b5e6-96231b3b80d8
SystemZ on Linux currently has 53-bit address space. In theory, the hardware
could support a full 64-bit address space, but that's not supported due to
kernel limitations (it'd require 5-level page tables), and there are no plans
for that. The default process layout stays within first 4TB of address space
(to avoid creating 4-level page tables), so any offset >= (1 << 42) is fine.
Let's use 1 << 52 here, ie. exactly half the address space.
I've originally used 7 << 50 (uses top 1/8th of the address space), but ASan
runtime assumes there's some space after the shadow area. While this is
fixable, it's simpler to avoid the issue entirely.
Also, I've originally wanted to have the shadow aligned to 1/8th the address
space, so that we can use OR like X86 to assemble the offset. I no longer
think it's a good idea, since using ADD enables us to load the constant just
once and use it with register + register indexed addressing.
Differential Revision: http://reviews.llvm.org/D19650
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@268161 91177308-0d34-0410-b5e6-96231b3b80d8
On OS X El Capitan and iOS 9, the linker supports a new section
attribute, live_support, which allows dead stripping to remove dead
globals along with the ASAN metadata about them.
With this change __asan_global structures are emitted in a new
__DATA,__asan_globals section on Darwin.
Additionally, there is a __DATA,__asan_liveness section with the
live_support attribute. Each entry in this section is simply a tuple
that binds together the liveness of a global variable and its ASAN
metadata structure. Thus the metadata structure will be alive if and
only if the global it references is also alive.
Review: http://reviews.llvm.org/D16737
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@264645 91177308-0d34-0410-b5e6-96231b3b80d8
llvm::getDISubprogram walks the instructions in a function, looking for one in the scope of the current function, so that it can find the !dbg entry for the subprogram itself.
Now that !dbg is attached to functions, this should not be necessary. This patch changes all uses to just query the subprogram directly on the function.
Ideally this should be NFC, but in reality its possible that a function:
has no !dbg (in which case there's likely a bug somewhere in an opt pass), or
that none of the instructions had a scope referencing the function, so we used to not find the !dbg on the function but now we will
Reviewed by Duncan Exon Smith.
Differential Revision: http://reviews.llvm.org/D18074
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@263184 91177308-0d34-0410-b5e6-96231b3b80d8
As discussed in https://github.com/google/sanitizers/issues/398, with current
implementation of poisoning globals we can have some CHECK failures or false
positives in case of mixing instrumented and non-instrumented code due to ASan
poisons innocent globals from non-sanitized binary/library. We can use private
aliases to avoid such errors. In addition, to preserve ODR violation detection,
we introduce new __odr_asan_gen_XXX symbol for each instrumented global that
indicates if this global was already registered. To detect ODR violation in
runtime, we should only check the value of indicator and report an error if it
isn't equal to zero.
Differential Revision: http://reviews.llvm.org/D15642
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260075 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: If the same pass manager is used for multiple modules ASAN
complains about GlobalsMD being initialized twice. Fix this by
resetting GlobalsMD in a new doFinalization method to allow this
use case.
Reviewers: kcc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D14962
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254851 91177308-0d34-0410-b5e6-96231b3b80d8
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). Similar to ppc64 port, aarch64 transformation
also requires to use an add instead of 'or' for 42-bit VMA.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252495 91177308-0d34-0410-b5e6-96231b3b80d8
inalloca variables were not treated as static allocas, therefore didn't
participate in regular stack instrumentation. We don't want them to
participate in dynamic alloca instrumentation as well.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@252213 91177308-0d34-0410-b5e6-96231b3b80d8
* Don't instrument promotable dynamic allocas:
We already have a test that checks that promotable dynamic allocas are
ignored, as well as static promotable allocas. Make sure this test will
still pass if/when we enable dynamic alloca instrumentation by default.
* Handle lifetime intrinsics before handling dynamic allocas:
lifetime intrinsics may refer to dynamic allocas, so we need to emit
instrumentation before these dynamic allocas would be replaced.
Differential Revision: http://reviews.llvm.org/D12704
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251045 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: In r231241, TargetLibraryInfoWrapperPass was added to
`getAnalysisUsage` for `AddressSanitizer`, but the corresponding
`INITIALIZE_PASS_DEPENDENCY` was not added.
Reviewers: dvyukov, chandlerc, kcc
Subscribers: kcc, llvm-commits
Differential Revision: http://reviews.llvm.org/D13629
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250813 91177308-0d34-0410-b5e6-96231b3b80d8
This is a simple refactoring that replaces Triple.getEnvironment()
checks for Android with Triple.isAndroid().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@249750 91177308-0d34-0410-b5e6-96231b3b80d8
These sections contain pointers to function that should be invoked
during startup/shutdown by __libc_csu_init and __libc_csu_fini.
Instrumenting these globals will append redzone to them, which will be
filled with zeroes. This will cause null pointer dereference at runtime.
Merge ASan regression tests for globals that should be ignored by
instrumentation pass.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247734 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@245594 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
returns_twice (most importantly, setjmp) functions are
optimization-hostile: if local variable is promoted to register, and is
changed between setjmp() and longjmp() calls, this update will be
undone. This is the reason why "man setjmp" advises to mark all these
locals as "volatile".
This can not be enough for ASan, though: when it replaces static alloca
with dynamic one, optionally called if UAR mode is enabled, it adds a
whole lot of SSA values, and computations of local variable addresses,
that can involve virtual registers, and cause unexpected behavior, when
these registers are restored from buffer saved in setjmp.
To fix this, just disable dynamic alloca and UAR tricks whenever we see
a returns_twice call in the function.
Reviewers: rnk
Subscribers: llvm-commits, kcc
Differential Revision: http://reviews.llvm.org/D11495
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243561 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243548 91177308-0d34-0410-b5e6-96231b3b80d8
We currently version `__asan_init` and when the ABI version doesn't match, the linker gives a `undefined reference to '__asan_init_v5'` message. From this, it might not be obvious that it's actually a version mismatch error. This patch makes the error message much clearer by changing the name of the undefined symbol to be `__asan_version_mismatch_check_xxx` (followed by the version string). We obviously don't want the initializer to be named like that, so it's a separate symbol that is used only for the purpose of version checking.
Reviewed at http://reviews.llvm.org/D11004
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@243003 91177308-0d34-0410-b5e6-96231b3b80d8
In r242510, non-instrumented allocas are now moved into the first basic block. This patch limits that to only move allocas that are present *after* the first instrumented one (i.e. only move allocas up). A testcase was updated to show behavior in these two cases. Without the patch, an alloca could be moved down, and could cause an invalid IR.
Differential Revision: http://reviews.llvm.org/D11339
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242883 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Arguments to llvm.localescape must be static allocas. They must be at
some statically known offset from the frame or stack pointer so that
other functions can access them with localrecover.
If we ever want to instrument these, we can use more indirection to
recover the addresses of these local variables. We can do it during
clang irgen or with the asan module pass.
Reviewers: eugenis
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11307
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242726 91177308-0d34-0410-b5e6-96231b3b80d8
Instrumentation and the runtime library were in disagreement about
ASan shadow offset on Android/AArch64.
This fixes a large number of existing tests on Android/AArch64.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242595 91177308-0d34-0410-b5e6-96231b3b80d8
Since r230724 ("Skip promotable allocas to improve performance at -O0"), there is a regression in the generated debug info for those non-instrumented variables. When inspecting such a variable's value in LLDB, you often get garbage instead of the actual value. ASan instrumentation is inserted before the creation of the non-instrumented alloca. The only allocas that are considered standard stack variables are the ones declared in the first basic-block, but the initial instrumentation setup in the function breaks that invariant.
This patch makes sure uninstrumented allocas stay in the first BB.
Differential Revision: http://reviews.llvm.org/D11179
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@242510 91177308-0d34-0410-b5e6-96231b3b80d8
It can be more robust than copying debug info from first non-alloca
instruction in the entry basic block. We use the same strategy in
coverage instrumentation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240738 91177308-0d34-0410-b5e6-96231b3b80d8
Do not instrument globals that are placed in sections containing "__llvm"
in their name.
This fixes a bug in ASan / PGO interoperability. ASan interferes with LLVM's
PGO, which places its globals into a special section, which is memcpy-ed by
the linker as a whole. When those goals are instrumented, ASan's memcpy wrapper
reports an issue.
http://reviews.llvm.org/D10541
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240723 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds initial support for the -fsanitize=kernel-address flag to Clang.
Right now it's quite restricted: only out-of-line instrumentation is supported, globals are not instrumented, some GCC kasan flags are not supported.
Using this patch I am able to build and boot the KASan tree with LLVMLinux patches from github.com/ramosian-glider/kasan/tree/kasan_llvmlinux.
To disable KASan instrumentation for a certain function attribute((no_sanitize("kernel-address"))) can be used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240131 91177308-0d34-0410-b5e6-96231b3b80d8