The bytecode compiler has a bug that was observed to cause a crash
with a specific signature when testing on FreeBSD.
This PR adds an index size check when looking up a constant to
prevent this crash in case a bugged signature gets through QA.
An additional NULL check is added just to be safe.
Also fixed a number of conditions where magic_scan() critical errors may
be ignored.
To ensure that the scan truly aborts for signature matches (not in
allmatch mode) and for timeouts, the `ctx->abort` option is now set in
these two conditions, and checked in several spots in magic_scan().
Additionally, I've consolidated some of the "scan must halt" type of
checks (mostly large switch statements) into a function so that we can
use the exact same logic in a few places in magic_scan().
I've also fixed a few minor warnings and code format issues.
The bytecode source files largely use `int` instead of the appropriate
`cl_errot_t` for clamav status codes, as well for boolean variables.
This hides warnings that would indicate bugs, and makes it harder to
read the code.
I haven't gone as in depth as with some other code cleanups. This
largely just replaces function interfactes and ret variables that use
`int` with `cl_error_t`. I also swapped a couple of `int`s to `bool`s.
While doing so I found that the `cli_bytecode_context_setpdf()` function
was incorrectly placed in the `bytecode_api.c` file instead of the next
to similar functions (`cli_bytecode_context_setpe`, etc.) in bytecode.c.
It's not an API function, so I moved it to the correct location.
I also eliminated a couple of compiler warnings:
- LLVM's CFG.h header emits a warning about a multi-line comment, so
that crops up with using LLVM for the bytecode runtime.
I disabled the warning through CMake.
- C doesn't like using the `inline` keyword on cli_dbgmsg in the
declaration in `bytecode2llvm.c` because we're compiling the bytecode
runtimes as a separate object file from the rest of libclamav.
It doesn't appear to be a functional issue, but I swapped that file
over to use `cli_dbgmsg_no_inline()` instead, just in case.
I would hope link-time-optimization will inline it anyways.
Refactored the clamscan code that determines 'what to scan' in order
to clean up some very messy logic and also to get around a difference in
how vscode and clang-format handle formatting #ifdef blocks in the
middle of an else/if.
In addition to refactoring, there is a slight behavior improvement. With
this change, doing `clamscan blah -` will now scan `blah` and then also
scan `stdin`. You can even do `clamscan - blah` to now scan `stdin` and
then scan `blah`. Before, The `-` had to be the only "filename" argument
in order to scan from stdin.
In addition, added a bunch of extra empty lines or changing multi-line
function calls to single-line function calls in order to get around a
bug in clang-format with these two options do not playing nice together:
- AlignConsecutiveAssignments: true
- AlignAfterOpenBracket: true
AlignAfterOpenBracket is not taking account the spaces inserted by
AlignConsecutiveAssignments, so you end up with stuff like this:
```c
bleeblah = 1;
blah = function(arg1,
arg2,
arg3);
// ^--- these args 4-left from where they should be.
```
VSCode, meanwhile, somehow fixes this whitespace issue so code that is
correctly formatted by VSCode doesn't have this bug, meaning that:
1. The clang-format check in GH Actions fails.
2. We'd all have to stop using format-on-save in VSCode and accept the
bug if we wanted those GH Actions tests to pass.
Adding an empty line before variable assignments from multi-line
function calls evades the buggy behavior.
This commit should resolve the clang-format github action test failures,
for now.
The `have_clamjit` global is used in the unit tests but doesn't appear
to be exported when I was testing the external LLVM runtime support PR,
resulting in an undefined symbol issue. Converting this to a function
that returns 0 or 1 instead of a global variable resolved the issue.
Modified bytecode JIT code to support llvm versions 8, 9, 10, 11, 12.
Additionally updated FindLLVM.cmake to the current version, found at
https://github.com/ldc-developers/ldc/blob/master/cmake/Modules/FindLLVM.cmake,
as well as making modifications suggested by Micah Snyder to check VERSION_LESS
in CMakeLists.txt to avoid having modifications to FindLLVM.cmake.
* Added loglevel parameter to logg()
* Fix logg and mprintf internals with new loglevels
* Update all logg calls to set loglevel
* Update all mprintf calls to set loglevel
* Fix hidden logg calls
* Executed clam-format
Previously we'd not clang-formatted the c++ bytecode files because:
A) It's a massive difference in format
B) I wasn't sure, at the time, which code was "ours"
Reformatting now that the LLVM source is all removed and before it gets
updated to support modern LLVM versions.
Have to manually link libtinfo (`-ltinfo`) because our FindLLVM
didn't add it to the LLVM_LIBRARIES variable for us. See:
- https://stackoverflow.com/questions/21477407/llvm-3-5-fails-to-link
Have to remove the CXX_STANDARD setting at the top of CMakeLists.txt
because of c++90 / c++11 ABI compatibility issues w/ LLVM. See:
- https://maleadt.github.io/LLVM.jl/dev/man/troubleshooting/
Rename "llvm/Config/config.h" "llvm/Config/llvm-config.h" because
LLVM renamed it in 2.8.
Have to link LLVM manually with the test binaries that use the
clamav object library instead of libclamav shared library.
CMake does not propagate library dependencies from object files.
I tested on ubuntu:16.04 with LLVM 3.6 built from source using:
```
/usr/local/bin/cmake .. -D CMAKE_INSTALL_PREFIX=/opt/llvm/3.6 \
-D LLVM_ENABLE_RTTI=ON
```
Then built clamav w/:
```
/usr/local/bin/cmake .. -D CMAKE_INSTALL_PREFIX=`pwd`/install \
-D BYTECODE_RUNTIME="llvm" \
-D LLVM_ROOT_DIR="/opt/llvm/3.6" \
-D LLVM_FIND_VERSION="3.6.0" && make && make install
```
This patch adds experimental-quality CMake build tooling.
The libmspack build required a modification to use "" instead of <> for
header #includes. This will hopefully be included in the libmspack
upstream project when adding CMake build tooling to libmspack.
Removed use of libltdl when using CMake.
Flex & Bison are now required to build.
If -DMAINTAINER_MODE, then GPERF is also required, though it currently
doesn't actually do anything. TODO!
I found that the autotools build system was generating the lexer output
but not actually compiling it, instead using previously generated (and
manually renamed) lexer c source. As a consequence, changes to the .l
and .y files weren't making it into the build. To resolve this, I
removed generated flex/bison files and fixed the tooling to use the
freshly generated files. Flex and bison are now required build tools.
On Windows, this adds a dependency on the winflexbison package,
which can be obtained using Chocolatey or may be manually installed.
CMake tooling only has partial support for building with external LLVM
library, and no support for the internal LLVM (to be removed in the
future). I.e. The CMake build currently only supports the bytecode
interpreter.
Many files used include paths relative to the top source directory or
relative to the current project, rather than relative to each build
target. Modern CMake support requires including internal dependency
headers the same way you would external dependency headers (albeit
with "" instead of <>). This meant correcting all header includes to
be relative to the build targets and not relative to the workspace.
For example, ...
```c
include "../libclamav/clamav.h"
include "clamd/clamd_others.h"
```
... becomes:
```c
// libclamav
include "clamav.h"
// clamd
include "clamd_others.h"
```
Fixes header name conflicts by renaming a few of the files.
Converted the "shared" code into a static library, which depends on
libclamav. The ironically named "shared" static library provides
features common to the ClamAV apps which are not required in
libclamav itself and are not intended for use by downstream projects.
This change was required for correct modern CMake practices but was
also required to use the automake "subdir-objects" option.
This eliminates warnings when running autoreconf which, in the next
version of autoconf & automake are likely to break the build.
libclamav used to build in multiple stages where an earlier stage is
a static library containing utils required by the "shared" code.
Linking clamdscan and clamdtop with this libclamav utils static lib
allowed these two apps to function without libclamav. While this is
nice in theory, the practical gains are minimal and it complicates
the build system. As such, the autotools and CMake tooling was
simplified for improved maintainability and this feature was thrown
out. clamdtop and clamdscan now require libclamav to function.
Removed the nopthreads version of the autotools
libclamav_internal_utils static library and added pthread linking to
a couple apps that may have issues building on some platforms without
it, with the intention of removing needless complexity from the
source. Kept the regular version of libclamav_internal_utils.la
though it is no longer used anywhere but in libclamav.
Added an experimental doxygen build option which attempts to build
clamav.h and libfreshclam doxygen html docs.
The CMake build tooling also may build the example program(s), which
isn't a feature in the Autotools build system.
Changed C standard to C90+ due to inline linking issues with socket.h
when linking libfreshclam.so on Linux.
Generate common.rc for win32.
Fix tabs/spaces in shared Makefile.am, and remove vestigial ifndef
from misc.c.
Add CMake files to the automake dist, so users can try the new
CMake tooling w/out having to build from a git clone.
clamonacc changes:
- Renamed FANOTIFY macro to HAVE_SYS_FANOTIFY_H to better match other
similar macros.
- Added a new clamav-clamonacc.service systemd unit file, based on
the work of ChadDevOps & Aaron Brighton.
- Added missing clamonacc man page.
Updates to clamdscan man page, add missing options.
Remove vestigial CL_NOLIBCLAMAV definitions (all apps now use
libclamav).
Rename Windows mspack.dll to libmspack.dll so all ClamAV-built
libraries have the lib-prefix with Visual Studio as with CMake.
If the watchdog thread is sleeping on a watchdog_item and
vm_execute_jit calls watchdog_disarm and returns before the watchdog wakes up,
then the watchdog thread will wake up and try to use the now uninitialized
item->abs_timeout.
Fix this by adding an in_use flag, and another condition variable.
watchdog_disarm now wakes the watchdog thread,
and waits till it releases the item.
Thanks to Michael Scheidell for providing feedback on this bug.
If the watchdog thread is sleeping on a watchdog_item and
vm_execute_jit calls watchdog_disarm and returns before the watchdog wakes up,
then the watchdog thread will wake up and try to use the now uninitialized
item->abs_timeout.
Fix this by adding an in_use flag, and another condition variable.
watchdog_disarm now wakes the watchdog thread,
and waits till it releases the item.
Thanks to Michael Scheidell for providing feedback on this bug.
Internal version is an LLVM 2.8 with 2 patches backported from LLVM 2.9 to fix a
crash on AVX chips.
So drop support for building with external LLVM 2.8, and add support for
building with external LLVM 2.9 instead.
Caveat:
stack smashing protection is broken on LLVM 2.9 so it is disabled
Example on Debian:
apt-get install llvm-2.9-dev
./configure --enable-llvm --with-system-llvm=/usr/bin/llvm-config-2.9
Don't create a new watchdog thread everytime a bytecode is run.
Instead try to reuse a previously create watchdog thread.
Watchdog thread will idle for a max of 10s, and then exit, and new watchdog being
created as needed.
Micah Snyder