Commit Graph

275 Commits

Author SHA1 Message Date
bernhardu
b8d857efac [win/asan] Populate test for function GetInstructionSize. (#118204)
This puts the content of GetInstructionSize into a test.
There are 5 cases missing, which I have already or would like to propose
a fix later.
2024-12-04 18:47:13 +01:00
bernhardu
a943922c0d [win/asan] GetInstructionSize: Remove duplicate instruction FF 25 .... (#116894)
It appears already some lines above with this comment:
  "Cannot overwrite control-instruction. Return 0 to indicate failure.".

Replacing just the comment in the first appearance.

Found after creating the test in #113085.
2024-11-29 09:17:37 +01:00
bernhardu
36b1811da4 [win/asan] Add a test skeleton for function GetInstructionSize. (#116948)
Was first part of PR #113085.
2024-11-26 11:02:48 +01:00
Hans
55f5d68c2d [win/asan] Recognize mov QWORD PTR [rip + X], reg (#117335)
This comes up when intercepting clang-built `__sanitizer_cov` functions.
2024-11-25 09:50:08 +01:00
bernhardu
6c52a18a1d [win/asan] GetInstructionSize: Fix 8A 05 ... to return 6 again. (#116889)
This was already the case before 3bd8f4e,
which probably accidentally inserted
a few new instructions and a return 4 in between.
2024-11-21 23:17:11 +02:00
bernhardu
b89e774672 [win/asan] Avoid warnings in compiling interception_win_test.cpp. (#116887)
Example:
  warning: unused variable 'kPatchableCode12' [-Wunused-const-variable]
2024-11-21 22:11:49 +02:00
Hans
cdfd4cff55 [win/asan] Search both higher and lower in AllocateTrampolineRegion (#114212)
There may not always be available virtual memory at higher addresses
than the target function. Therefore, search also lower addresses while
ensuring that we stay within the accessible memory range.

Additionally, add more ReportError calls to make the reasons for
interception failure more clear.
2024-11-05 10:06:39 +01:00
Hans Wennborg
8417f6af54 [win/asan] Fix instruction size for 44 0f b6 1a
movzx  r11d,BYTE PTR [rdx]

is four bytes long.

Follow-up to #111638
2024-10-21 17:55:47 +02:00
Mike Hommey
ce4618a9c4 [ASan][windows] Recognize movzx r11d, BYTE PTR [rdx] in interception_win (#111638)
The instruction is present in some library in the 24H2 update for
Windows 11:

==8508==interception_win: unhandled instruction at 0x7ff83e193a40: 44 0f
b6 1a 4c 8b d2 48

This could be generalized, but getting all the ModR/M byte combinations
right is tricky. Many other classes of instructions handled in this file
could use some generalization too.
2024-10-18 12:42:03 +00:00
Charlie Barto
3bd8f4e0a0 [sanitizer][asan][msvc] Teach GetInstructionSize about many instructions that appear in MSVC generated code. (#69490)
MSVC can sometimes generate instructions in function prologues that asan
previously didn't know the size of. This teaches asan those sizes. This isn't
super useful for using ASAN with non-msvc compilers, but it does stand alone.

From https://reviews.llvm.org/D151008
2024-09-19 15:44:08 +02:00
Hans Wennborg
04ccbe6e70 Fix typos in interception_win.cpp 2024-09-19 13:11:10 +02:00
Hans
3d2925b9de [win/asan] AllocateMemoryForTrampoline within 2 GB of the module's base address (#108822)
Since we may copy code (see CopyInstructions) to the trampoline which
could reference data inside the original module, we really want the
trampoline to be within 2 GB of not just the original function, but
within anything that function may have rip-relative accesses to, i.e.
within 2 GB of that function's whole module.

This fixes interception failures like the following scenario:

1. Intercept `CreateProcess` in kernel32.dll, allocating a trampoline
region right after
2. Start intercepting `memcpy` in the main executable, which is loaded
at a lower address than kernel32.dll, but still within 2 GB of the
trampoline region so we keep using it.
3. Try to copy instructions from `memcpy` to the trampoline. Turns out
one instruction references data that is more than 2GB away from the
trampoline, so it can't be relocated.
4. The process exits due to a CHECK failure

(Full story at https://crbug.com/341936875#comment45 and following.)
2024-09-18 08:58:14 +02:00
Charlie Barto
53a81d4d26 Reland [asan][windows] Eliminate the static asan runtime on windows (#107899)
This reapplies 8fa66c6ca7 ([asan][windows]
Eliminate the static asan runtime on windows) for a second time.

That PR bounced off the tests because it caused failures in the other
sanitizer runtimes, these have been fixed by only building interception,
sanitizer_common, and asan with /MD, and continuing to build the rest of
the runtimes with /MT. This does mean that any usage of the static
ubsan/fuzzer/etc runtimes will mean you're mixing different runtime
library linkages in the same app, the interception, sanitizer_common,
and asan runtimes are designed for this, however it does result in some
linker warnings.

Additionally, it turns out when building in release-mode with
LLVM_ENABLE_PDBs the build system forced /OPT:ICF. This totally breaks
asan's "new" method of doing "weak" functions on windows, and so
/OPT:NOICF was explicitly added to asan's link flags.

---------

Co-authored-by: Amy Wishnousky <amyw@microsoft.com>
2024-09-09 13:41:08 -07:00
Alex Richardson
46fe36a429 Revert "[compiler-rt] Remove duplicates of sanitizer_common functions"
This works for MinGW, but the MSVC linker apparently doens't pull in
those symbols. Reverting for now since I won't be able to reproduce it today.

https://lab.llvm.org/buildbot/#/builders/107/builds/2337

This reverts commit 9df92cbd1a.
2024-08-29 17:29:01 -07:00
Alexander Richardson
9df92cbd1a [compiler-rt] Remove duplicates of sanitizer_common functions
These functions in interception_win.cpp already exist in
sanitizer_common. Use those instead.

Reviewed By: mstorsjo

Pull Request: https://github.com/llvm/llvm-project/pull/106488
2024-08-29 16:00:44 -07:00
Alexander Richardson
ec68dc1ca4 [compiler-rt] Work around incompatible Windows definitions of (S)SIZE_T
The interceptor types are supposed to match size_t (and the non-Windows
ssize_t) exactly, but on 32-bit Windows `size_t` uses `unsigned int`
whereas `SIZE_T` is `unsigned long`. The current definition results in
`uptr` not matching `uintptr_t` since we otherwise get typedef
redefinition errors. Work around this by using a #define instead of
a typedef when defining SIZE_T.

It would probably be cleaner to stop using these uppercase types, but
that is a rather invasive change and this one is the minimal change to
allow uptr to match uintptr_t on Windows.

To ensure this compiles on Windows, we also remove the interceptor.h
defines of uptr (that do not always match __sanitizer::uptr) and rely
on __sanitizer::uptr instead. The interceptor types most likely predate
those other types so clean up the unnecessary definition while here.

This also reverts commit 18e06e3e2f and
commit bb27dd853a.

Reviewed By: mstorsjo, vitalybuka

Pull Request: https://github.com/llvm/llvm-project/pull/106311
2024-08-29 15:59:26 -07:00
Nikita Popov
155b7a1282 [Sanitizers] Avoid overload ambiguity for interceptors (#100986)
Since glibc 2.40 some functions like openat make use of overloads when
built with `-D_FORTIFY_SOURCE=2`, see:
https://github.com/bminor/glibc/blob/master/io/bits/fcntl2.h

This means that doing something like `(uintptr_t) openat` or `(void *)
openat` is now ambiguous, breaking the compiler-rt build on new glibc
versions.

Fix this by explicitly casting the symbol to the expected function type
before casting it to an intptr. The expected type is obtained as
`decltype(REAL(func))` so we don't have to repeat the signature from
INTERCEPTOR in the INTERCEPT_FUNTION macro.

Fixes https://github.com/llvm/llvm-project/issues/100754.
2024-07-30 09:25:03 +02:00
Michael Kruse
a35ac42fac [compiler-rt] Revise IDE folder structure (#89753)
Update the folder titles for targets in the monorepository that have not
seen taken care of for some time. These are the folders that targets are
organized in Visual Studio and XCode
(`set_property(TARGET <target> PROPERTY FOLDER "<title>")`)
when using the respective CMake's IDE generator.

 * Ensure that every target is in a folder
 * Use a folder hierarchy with each LLVM subproject as a top-level folder
 * Use consistent folder names between subprojects
 * When using target-creating functions from AddLLVM.cmake, automatically
deduce the folder. This reduces the number of
`set_property`/`set_target_property`, but are still necessary when
`add_custom_target`, `add_executable`, `add_library`, etc. are used. A
LLVM_SUBPROJECT_TITLE definition is used for that in each subproject's
root CMakeLists.txt.
2024-06-04 09:26:45 +02:00
Charlie Barto
423832421b [asan][windows] Weak function interception support in instruction size decoder. (#86570)
This makes it so we'll be able to decode the instructions used in the
weak function stubs from
https://github.com/llvm/llvm-project/pull/81677. This code doesn't
technically require those changes.

Co-authored-by: Amy Wishnousky <amyw@microsoft.com>
2024-03-28 09:52:25 -07:00
Zack Johnson
4b10d1fdd3 [compiler-rt] Fixing UB on Windows for trampoline allocations (#85639)
Fixing the type of the constant to avoid undefined behavior with respect
to overflow.
2024-03-19 15:16:18 +02:00
Alexander Richardson
55b90b5140 [compiler-rt] Remove llvm_gtest dependency from unit tests
All these unit tests already include ${COMPILER_RT_GTEST_SOURCE} as an
input source file and the target llvm_gtest does not exist for
standalone builds. Currently the DEPS argument is ignored for standalone
builds so the missing target is not a problem, but as part of fixing a
build race for standalone builds I am planning to include those
dependencies in COMPILER_RT_TEST_STANDALONE_BUILD_LIBS configurations.

Reviewed By: vitalybuka

Pull Request: https://github.com/llvm/llvm-project/pull/83649
2024-03-13 11:28:44 -07:00
Marco Elver
1c792d24e0 [compiler-rt] Fix interceptors with AArch64 BTI (#84061)
On AArch64 with BTI, we have to start functions with the appropriate
BTI hint to indicate that the function is a valid call target.

To support interceptors with AArch64 BTI, add "BTI c".
2024-03-13 09:01:00 +01:00
Fangrui Song
8443ce563b [sanitizer] Lift AsanDoesNotSupportStaticLinkage to sanitizer_common.h. NFC (#80948)
The `_DYNAMIC` reference from `AsanDoesNotSupportStaticLinkage` ensures
that `clang++ -fsanitize=address -static` gets a linker error.
`MemprofDoesNotSupportStaticLinkage` is similar for `-fmemory-profile`.
Move the functions to sanitizer_common.h to be used by more sanitizers
on ELF platforms.

Fuchsia does not use interposition and opts out the check (its
`AsanDoesNotSupportStaticLinkage` is a no-op).
2024-02-16 19:36:39 -08:00
YunQiang Su
0a64367a72 Sanitizer/MIPS: Use $t9 for preemptible function call (#76894)
Currently, almost all of the shared libraries of MIPS, rely on $t9
to get the address of current function, instead of PCREL instructions,
even on MIPSr6. So we have to set $t9 properly.

To get the address of preemptible function, we need the help of GOT.
MIPS/O32 has .cpload, which can help to generate 3 instructions to get GOT.
For __mips64, we can get GOT by:

lui $t8, %hi(%neg(%gp_rel(SANITIZER_STRINGIFY(TRAMPOLINE(func)))))
daddu $t8, $t8, $t9
daddiu $t8, $t8, %hi(%neg(%gp_rel(SANITIZER_STRINGIFY(TRAMPOLINE(func)))))

And then get the address of __interceptor_func, and jump to it

ld $t9, %got_disp(_interceptor" SANITIZER_STRINGIFY(func) ")($t8)
jr $t9

Fixes #74047

Co-authored-by: YunQiang Su <yunqiang.su@cipunited.com>
2024-01-16 23:11:50 -05:00
Charlie Barto
41b09bbe98 [ASAN][sanitizers][win] Allow windows-asan to be built with /MDd and intercept functions from the debug runtimes. (#77840)
It turns out this works _mostly_ fine, even when mixing debug versions
of asan with programs built with the release runtime. Using /MT (or
/MTd) with a dynamically linked asan has never really worked that well,
and I am planning on opening a PR that will completely remove the
static-asan configuration for windows and make programs linked with the
static CRT/runtime work with the DLL version of asan. This is better
than the current situation because the static linked version of asan
doesn't work well on windows if there are multiple DLLs in the process
using it.

The check for building asan with only /MD or /MT has been removed. It
was in AsanDoesNotSupportStaticLinkage, but was checking for debug CRTs,
not static linkage. The kind of static linkage this function is supposed
to check for (on linux for example) doesn't really exist on windows.

Note: There is one outstanding issue with this approach, if you mix a
/MDd DLLs and /MD dlls in the same process then the "real" function
called by asan interceptors will be the same for calls from both
contexts, potentially screwing up things like errno. This only happens
if you mix /MD and /MDd in the same process, because otherwise asan
won't find functions from both runtimes to intercept. We are working on
a fix for this, and it mainly hits with the CRT functions exported from
both ucrtbase and ntdll.


This change is being upstreamed from Microsoft's fork.
2024-01-16 13:19:03 -08:00
Zack Johnson
cbe27c45cd [ASan][Windows] Interception fix for 'mov al, byte ptr []' sequences (#72531) 2023-12-07 10:17:58 -05:00
Farzon Lotfi
d79aee9f73 Changes to support running tests for Windows arm64 asan (#66973)
1. Differentiate SANITIZER_WINDOWS64 for x64 and arm64
2. turn off interception tests that expect x86 assembly

---------

Co-authored-by: Farzon Lotfi <farzon@farzon.com>
2023-11-27 12:28:44 -05:00
Marco Elver
a855a16a02 [compiler-rt] Fix interceptors with Solaris as (#72973)
Jakub Jelínek reports:

As mentioned in https://gcc.gnu.org/PR112563, the new DECLARE_WRAPPER
macro
added in 37445e9 and ammended in 85d3873 doesn't work on SPARC/Solaris
with
  Solaris as.

While clang and GNU as when used from GCC seems to be forgiving on most
architectures and allow both %function and @function (with the latter
not being
allowed on ARM/AArch64 I believe because @ is assembler comment start
there),
  Solaris as doesn't allow the %function form.

Fix it by using %function only for ARM.

Co-developed-by: Jakub Jelínek <jakub@redhat.com>
Reported-by: Jakub Jelínek <jakub@redhat.com>
Closes: https://github.com/llvm/llvm-project/issues/72970
2023-11-21 20:48:01 +01:00
nicole mazzuca
160e8eb449 [ASan] Recognize lea r10, [rip + XX] (#68910)
This instruction is present in memcpy in the latest vcruntime

This PR has been opened for @AndrewDeanMS (a teammate inside Microsoft)
who made the PR to our internal branch.

Co-authored-by: Andrew Dean <Andrew.Dean@microsoft.com>
2023-10-13 08:47:23 -07:00
nicole mazzuca
bc34a83380 [ASan][Windows] Fix rip-relative instruction replacement (#68432)
The old code incorrectly checked what relative offsets were allowed.

The correct check is that the offset from the target to the instruction
pointer should be within $[-2^{31}, 2^{31})$; however, the check that
was originally written was that the offset was within $[0, 2^{31})$.
Negative offsets are certainly allowable (as long as they fit in 32
bits), and this change fixes that.
2023-10-09 14:53:07 -07:00
Alexandre Ganea
2385cf66e2 [compiler-rt] Fix "interception" file name 2023-10-02 12:29:29 -04:00
Alexandre Ganea
262e2886b8 [compiler-rt] Fix MSVC /external detection in cmake scripts
As suggested by https://reviews.llvm.org/D116872#4650507

Differential Revision: https://reviews.llvm.org/D116872
2023-10-02 12:29:28 -04:00
Farzon Lotfi
5a48a824aa [compiler-rt] Fix interception_win.cpp arm64 instruction lengths
Updates GetInstructionSize to account for arm64 instruction sizes.

ARM64 instruction are always 4 bytes long but GetInstructionSize in
interception_win.cpp assumes x86_64 which has mixed sizes.

Fix is for: https://github.com/llvm/llvm-project/issues/64319

Before the changeclang_rt.asan_dynamic-aarch64.dll would crash at:
OverrideFunction -> OverrideFunctionWithHotPatch -> GetInstructionSize:825

After the change:
dllthunkintercept -> dllthunkgetrealaddressordie -> InternalGetProcAddress
2023-09-12 22:43:51 -04:00
Shoaib Meenai
dcafbd0c67 [compiler-rt] Remove explicit Android libatomic linking
The comments date back to NDK r10, which is ancient. libatomic isn't
always needed anymore, and even when it is, it's bundled into
compiler-rt in the NDK so we'll get it automatically. Remove the
unnecessary explicit links.

Reviewed By: srhines

Differential Revision: https://reviews.llvm.org/D158793
2023-08-28 17:34:48 -07:00
Jessica Clarke
7e1afab1b1 [compiler-rt] Use .globl for FreeBSD/NetBSD interceptor wrappers
On FreeBSD and NetBSD we don't use .weak due to differing semantics.
Currently we end up using no directive, which gives a local symbol,
whereas the closer thing to a weak symbol would be a global one. In
particular, both GNU and LLVM toolchains cannot handle a GOT-indirect
reference to a local symbol at a non-zero offset within a section on
AArch64 (see https://github.com/ARM-software/abi-aa/issues/217), and so
interceptors do not work on FreeBSD/arm64, failing to link with LLD.
Switching to .globl both works around this bug and more closely aligns
such non-weak platforms with weak ones.

Fixes https://github.com/llvm/llvm-project/issues/63418

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D158552
2023-08-22 23:38:24 +01:00
Gabor Horvath
8330116ebd Revert "ASan: Add additional wcs* interceptors on Windows" to unbreak build bot
This reverts commit c0c83668f8.
2023-08-21 15:45:51 -07:00
Nicole Mazzuca
c0c83668f8 ASan: Add additional wcs* interceptors on Windows
This adds wcs[n]cat, wcs[n]cmp, wcs[n]cpy, and wcschr functions to the
interception code on Windows; wcs[n]cat was already intercepted, but only on
POSIX.

Differential Revision: https://reviews.llvm.org/D157038
2023-08-21 14:17:42 -07:00
Marco Elver
85d3873a45 Fix "[compiler-rt] Allow 3 simultaneous interceptors on Linux"
Fix inline asm trampoline type. Some architectures will complain:

<inline asm>:8:41: error: expected STT_<TYPE_IN_UPPER_CASE>, '#<type>', '%<type>' or "<type>"
    8 | .type  __interceptor_trampoline_malloc, @function

Just use %function instead, which is what is also used in
sanitizer_asm.h
2023-06-09 12:14:45 +02:00
Marco Elver
37445e96d8 [compiler-rt] Allow 3 simultaneous interceptors on Linux
Rework Linux (and *BSD) interceptors to allow for up to 3 (2 for *BSD)
simultaneous interceptors. See code comments for details.

The main motivation is to support new sampling sanitizers (in the spirit
of GWP-ASan), that have to intercept few functions. Unfortunately, the
reality is that there are user interceptors that exist in the wild.

To support foreign user interceptors, foreign dynamic analysis
interceptors, and compiler-rt interceptors all at the same time,
including any combination of them, this change enables up to 3
interceptors on Linux (2 on *BSD).

v2:
* Revert to to the simpler "weak wrapper -(alias)-> __interceptor"
  scheme on architectures that cannot implement a trampoline efficiently
  due to complexities of resolving a preemptible symbol (PowerPC64
  ELFv2 global entry, and i386 PIC).
* Avoid duplicate intercepted functions in gen_dynamic_list.py, due to
  matching __interceptor_X and ___interceptor_X.
* Fix s390 __tls_get_offset.

Reviewed By: dvyukov, MaskRay, vitalybuka

Differential Revision: https://reviews.llvm.org/D151085
2023-06-09 11:30:41 +02:00
Marco Elver
4d927fc035 [compiler-rt] Reformat interception macros
Reformat interception macros to be more readable.

NFC.
2023-06-09 10:43:37 +02:00
Marco Elver
33388d8c0b Revert "[compiler-rt] Allow 3 simultaneous interceptors on Linux"
This reverts commit 57882fe76e.
This reverts commit 74b0ac571b.

Breaks various build bots.
2023-06-07 10:16:24 +02:00
Marco Elver
74b0ac571b [compiler-rt] Allow 3 simultaneous interceptors on Linux
Rework Linux (and *BSD) interceptors to allow for up to 3 (2 for *BSD)
simultaneous interceptors. See code comments for details.

The main motivation is to support new sampling sanitizers (in the spirit
of GWP-ASan), that have to intercept few functions. Unfortunately, the
reality is that there are user interceptors that exist in the wild.

To support foreign user interceptors, foreign dynamic analysis
interceptors, and compiler-rt interceptors all at the same time,
including any combination of them, this change enables up to 3
interceptors on Linux (2 on *BSD).

Reviewed By: dvyukov, MaskRay, vitalybuka

Differential Revision: https://reviews.llvm.org/D151085
2023-06-07 09:06:31 +02:00
Marco Elver
0a71e25e24 [compiler-rt] Avoid memintrinsic calls inserted by the compiler
D135716 introduced -ftrivial-auto-var-init=pattern where supported.
Unfortunately this introduces unwanted memset() for large stack arrays,
as shown by the new tests added for asan and msan (tsan already had this
test).

In general, the problem of compiler-inserted memintrinsic calls
(memset/memcpy/memmove) is not new to compiler-rt, and has been a
problem before.

To avoid introducing unwanted memintrinsic calls, we redefine
memintrinsics as __sanitizer_internal_mem* at the assembly level for
most source files automatically (where sanitizer_common_internal_defs.h
is included).

In few cases, redefining a symbol in this way causes issues for
interceptors, namely the memintrinsic interceptor themselves. For such
source files we have to selectively disable the redefinition.

Other alternatives have been considered, but simply do not work well in
the context of compiler-rt:

	1. Linker --wrap:  this does not work because --wrap only
	   applies to the final link, and would not apply when building
	   sanitizer static libraries.

	2. Changing references to memset() via objcopy:  this may work,
	   but due to the complexities of the build system, introducing
	   such a post-processing step for the right object files (in
	   particular object files defining memset cannot be touched)
	   seems infeasible.

The chosen solution works well (as shown by the tests). Other libraries
have chosen the same solution where nothing else works (see e.g. glibc's
"symbol-hacks.h").

v4:
- Add interface attribute to __sanitizer_internal_mem* declarations as
  well, as otherwise some compilers (MSVC) will complain.
- Add SANITIZER_COMMON_NO_REDEFINE_BUILTINS to source files using
  C++STL, since this could lead to ODR violations (see added comment).

v3:
- Don't use ALIAS() to alias internal_mem*() functions to
  __sanitizer_internal_mem*() functions, but just define them as
  ALWAYS_INLINE functions instead. This will work on darwin and windows.

v2:
- Fix ubsan_minimal build where compiler decides to insert
  memset/memcpy: ubsan_minimal has work without RTSanitizerCommonLibc,
  therefore do not redefine the builtins.
- Fix definition of internal_mem* functions with compilers that want the
  aliased function to already be defined before.
- Fix definition of __sanitizer_internal_mem* functions with compilers
  more pedantic about attribute placement around extern "C".

Reviewed By: vitalybuka, dvyukov

Differential Revision: https://reviews.llvm.org/D151152
2023-06-06 16:10:45 +02:00
Marco Elver
8e54794867 Revert "[compiler-rt] Avoid memintrinsic calls inserted by the compiler"
This reverts commit fc011a7288.
This reverts commit 4ad6a0c9a4.
This reverts commit 4b1eb4cf0e.

Still causes Windows build bots to fail.
2023-06-02 16:37:38 +02:00
Marco Elver
4b1eb4cf0e [compiler-rt] Avoid memintrinsic calls inserted by the compiler
D135716 introduced -ftrivial-auto-var-init=pattern where supported.
Unfortunately this introduces unwanted memset() for large stack arrays,
as shown by the new tests added for asan and msan (tsan already had this
test).

In general, the problem of compiler-inserted memintrinsic calls
(memset/memcpy/memmove) is not new to compiler-rt, and has been a
problem before.

To avoid introducing unwanted memintrinsic calls, we redefine
memintrinsics as __sanitizer_internal_mem* at the assembly level for
most source files automatically (where sanitizer_common_internal_defs.h
is included).

In few cases, redefining a symbol in this way causes issues for
interceptors, namely the memintrinsic interceptor themselves. For such
source files we have to selectively disable the redefinition.

Other alternatives have been considered, but simply do not work well in
the context of compiler-rt:

	1. Linker --wrap:  this does not work because --wrap only
	   applies to the final link, and would not apply when building
	   sanitizer static libraries.

	2. Changing references to memset() via objcopy:  this may work,
	   but due to the complexities of the build system, introducing
	   such a post-processing step for the right object files (in
	   particular object files defining memset cannot be touched)
	   seems infeasible.

The chosen solution works well (as shown by the tests). Other libraries
have chosen the same solution where nothing else works (see e.g. glibc's
"symbol-hacks.h").

v3:
- Don't use ALIAS() to alias internal_mem*() functions to
  __sanitizer_internal_mem*() functions, but just define them as
  ALWAYS_INLINE functions instead. This will work on darwin and windows.

v2:
- Fix ubsan_minimal build where compiler decides to insert
  memset/memcpy: ubsan_minimal has work without RTSanitizerCommonLibc,
  therefore do not redefine the builtins.
- Fix definition of internal_mem* functions with compilers that want the
  aliased function to already be defined before.
- Fix definition of __sanitizer_internal_mem* functions with compilers
  more pedantic about attribute placement around extern "C".

Reviewed By: vitalybuka, dvyukov

Differential Revision: https://reviews.llvm.org/D151152
2023-06-02 15:39:00 +02:00
Marco Elver
8e728adcfe Revert "[compiler-rt] Avoid memintrinsic calls inserted by the compiler"
This reverts commit 4369de7af4.

Fails on Mac OS with "sanitizer_libc.cpp:109:5: error: aliases are not
supported on darwin".
2023-05-31 17:59:11 +02:00
Marco Elver
4369de7af4 [compiler-rt] Avoid memintrinsic calls inserted by the compiler
D135716 introduced -ftrivial-auto-var-init=pattern where supported.
Unfortunately this introduces unwanted memset() for large stack arrays,
as shown by the new tests added for asan and msan (tsan already had this
test).

In general, the problem of compiler-inserted memintrinsic calls
(memset/memcpy/memmove) is not new to compiler-rt, and has been a
problem before.

To avoid introducing unwanted memintrinsic calls, we redefine
memintrinsics as __sanitizer_internal_mem* at the assembly level for
most source files automatically (where sanitizer_common_internal_defs.h
is included).

In few cases, redefining a symbol in this way causes issues for
interceptors, namely the memintrinsic interceptor themselves. For such
source files we have to selectively disable the redefinition.

Other alternatives have been considered, but simply do not work well in
the context of compiler-rt:

	1. Linker --wrap:  this does not work because --wrap only
	   applies to the final link, and would not apply when building
	   sanitizer static libraries.

	2. Changing references to memset() via objcopy:  this may work,
	   but due to the complexities of the build system, introducing
	   such a post-processing step for the right object files (in
	   particular object files defining memset cannot be touched)
	   seems infeasible.

The chosen solution works well (as shown by the tests). Other libraries
have chosen the same solution where nothing else works (see e.g. glibc's
"symbol-hacks.h").

v2:
- Fix ubsan_minimal build where compiler decides to insert
  memset/memcpy: ubsan_minimal has work without RTSanitizerCommonLibc,
  therefore do not redefine the builtins.
- Fix definition of internal_mem* functions with compilers that want the
  aliased function to already be defined before.
- Fix definition of __sanitizer_internal_mem* functions with compilers
  more pedantic about attribute placement around extern "C".

Reviewed By: vitalybuka, dvyukov

Differential Revision: https://reviews.llvm.org/D151152
2023-05-31 16:58:53 +02:00
Marco Elver
26bda9e95a Revert "[compiler-rt] Avoid memintrinsic calls inserted by the compiler"
This reverts commit e614d5667f.

Build bot failures:

| FAILED: lib/clang/17/lib/linux/libclang_rt.ubsan_minimal-i386.so
| : && /usr/bin/clang++ -fPIC -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -Wall -Wno-unused-parameter -O3 -DNDEBUG  -Wl,-z,defs -Wl,-z,nodelete   -m32 -nodefaultlibs -Wl,-z,text -nostdlib++ -shared -Wl,-soname,libclang_rt.ubsan_minimal-i386.so -o lib/clang/17/lib/linux/libclang_rt.ubsan_minimal-i386.so projects/compiler-rt/lib/ubsan_minimal/CMakeFiles/RTUbsan_minimal.i386.dir/ubsan_minimal_handlers.cpp.o  -lgcc_s  -lc && :
| /usr/bin/ld: projects/compiler-rt/lib/ubsan_minimal/CMakeFiles/RTUbsan_minimal.i386.dir/ubsan_minimal_handlers.cpp.o: in function `__ubsan_handle_type_mismatch_minimal':
| /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/compiler-rt/lib/ubsan_minimal/ubsan_minimal_handlers.cpp:120: undefined reference to `__sanitizer_internal_memcpy'
| /usr/bin/ld: projects/compiler-rt/lib/ubsan_minimal/CMakeFiles/RTUbsan_minimal.i386.dir/ubsan_minimal_handlers.cpp.o: in function `__ubsan_handle_type_mismatch_minimal_abort':
| /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/compiler-rt/lib/ubsan_minimal/ubsan_minimal_handlers.cpp:120: undefined reference to `__sanitizer_internal_memcpy'
| /usr/bin/ld: projects/compiler-rt/lib/ubsan_minimal/CMakeFiles/RTUbsan_minimal.i386.dir/ubsan_minimal_handlers.cpp.o: in function `__ubsan_handle_alignment_assumption_minimal':
| /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/compiler-rt/lib/ubsan_minimal/ubsan_minimal_handlers.cpp:121: undefined reference to `__sanitizer_internal_memcpy'
| /usr/bin/ld: projects/compiler-rt/lib/ubsan_minimal/CMakeFiles/RTUbsan_minimal.i386.dir/ubsan_minimal_handlers.cpp.o: in function `__ubsan_handle_alignment_assumption_minimal_abort':
| /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/compiler-rt/lib/ubsan_minimal/ubsan_minimal_handlers.cpp:121: undefined reference to `__sanitizer_internal_memcpy'
| /usr/bin/ld: projects/compiler-rt/lib/ubsan_minimal/CMakeFiles/RTUbsan_minimal.i386.dir/ubsan_minimal_handlers.cpp.o: in function `__ubsan_handle_add_overflow_minimal':
| /b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/compiler-rt/lib/ubsan_minimal/ubsan_minimal_handlers.cpp:122: undefined reference to `__sanitizer_internal_memcpy'
| /usr/bin/ld: projects/compiler-rt/lib/ubsan_minimal/CMakeFiles/RTUbsan_minimal.i386.dir/ubsan_minimal_handlers.cpp.o:/b/sanitizer-x86_64-linux-bootstrap-msan/build/llvm-project/compiler-rt/lib/ubsan_minimal/ubsan_minimal_handlers.cpp:122: more undefined references to `__sanitizer_internal_memcpy' follow

Link: https://lab.llvm.org/buildbot#builders/74/builds/19569
2023-05-31 12:20:19 +02:00
Marco Elver
e614d5667f [compiler-rt] Avoid memintrinsic calls inserted by the compiler
D135716 introduced -ftrivial-auto-var-init=pattern where supported.
Unfortunately this introduces unwanted memset() for large stack arrays,
as shown by the new tests added for asan and msan (tsan already had this
test).

In general, the problem of compiler-inserted memintrinsic calls
(memset/memcpy/memmove) is not new to compiler-rt, and has been a
problem before.

To avoid introducing unwanted memintrinsic calls, we redefine
memintrinsics as __sanitizer_internal_mem* at the assembly level for
most source files automatically (where sanitizer_common_internal_defs.h
is included).

In few cases, redefining a symbol in this way causes issues for
interceptors, namely the memintrinsic interceptor themselves. For such
source files we have to selectively disable the redefinition.

Other alternatives have been considered, but simply do not work well in
the context of compiler-rt:

	1. Linker --wrap:  this does not work because --wrap only
	   applies to the final link, and would not apply when building
	   sanitizer static libraries.

	2. Changing references to memset() via objcopy:  this may work,
	   but due to the complexities of the build system, introducing
	   such a post-processing step for the right object files (in
	   particular object files defining memset cannot be touched)
	   seems infeasible.

The chosen solution works well (as shown by the tests). Other libraries
have chosen the same solution where nothing else works (see e.g. glibc's
"symbol-hacks.h").

Reviewed By: vitalybuka, dvyukov

Differential Revision: https://reviews.llvm.org/D151152
2023-05-31 11:50:13 +02:00
Marco Elver
19b137f0c2 [compiler-rt] Unify Linux and *BSD interceptors more
The Linux and *BSD interceptors are almost identical, except for *BSD,
where the overridden intercepted function is not defined weak due to
some incompliant linker behaviour.

Since most of the interception machinery is shared between Linux and
*BSD (see INTERCEPT_FUNCTION macro), it makes sense to unify interceptor
definition and declarations as much as possible to ease future changes.

NFC.

Reviewed By: dvyukov, vitalybuka

Differential Revision: https://reviews.llvm.org/D151318
2023-05-25 12:01:10 +02:00