As we have repplaced fork-based fuzzing, with reboots - we can no longer
use a timeout+exit() to avoid slow inputs. Libfuzzer has its own timer
that it uses to catch slow inputs, however these timeouts are usually
seconds-minutes long: more than enough to bog-down the fuzzing process.
However, I found that slow inputs often attempt to fill overly large DMA
requests. Thus, we can mitigate most timeouts by setting a cap on the
total number of DMA bytes written by an input.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
As we are converting most fuzzers to rely on reboots to reset state,
introduce an API to make sure reboots are invoked in a consistent
manner.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
PCIDeviceClass and PCIDevice are defined in pci.h. Many users of the
header don't actually need them. Similar structs live in their own
headers: PCIBusClass and PCIBus in pci_bus.h, PCIBridge in
pci_bridge.h, PCIHostBridgeClass and PCIHostState in pci_host.h,
PCIExpressHost in pcie_host.h, and PCIERootPortClass, PCIEPort, and
PCIESlot in pcie_port.h.
Move PCIDeviceClass and PCIDeviceClass to new pci_device.h, along with
the code that needs them. Adjust include directives.
This also enables the next commit.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221222100330.380143-6-armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The has_FOO for pointer-valued FOO are redundant, except for arrays.
They are also a nuisance to work with. Recent commit "qapi: Start to
elide redundant has_FOO in generated C" provided the means to elide
them step by step. This is the step for qapi/qdev.json and
qapi/qom.json.
Said commit explains the transformation in more detail. The invariant
violations mentioned there do not occur here.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Daniel P. Berrangé <berrange@redhat.com>
Cc: Eduardo Habkost <eduardo@habkost.net>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221104160712.3005652-21-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
This case was written to use hardcoded /tmp directory for temporary
files. Update to use g_file_open_tmp() for a portable implementation.
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220925113032.1949844-12-bmeng.cn@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
This case was written to use hardcoded /tmp directory for temporary
files. Update to use g_dir_make_tmp() for a portable implementation.
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220925113032.1949844-11-bmeng.cn@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
This work is based on:
https://patchew.org/QEMU/20220317125534.38706-1-philippe.mathieu.daude@gmail.com/
Simplify the initialization dance by running qemu_init() in the main
thread before the Cocoa event loop starts. The secondary thread only
runs only qemu_main_loop() and qemu_cleanup().
This fixes a case where addRemovableDevicesMenuItems() calls
qmp_query_block() while expecting the main thread to still hold
the BQL.
Overriding the code after calling qemu_init() is done by dynamically
replacing a function pointer variable, qemu_main when initializing
ui/cocoa, which unifies the static implementation of main() for
builds with ui/cocoa and ones without ui/cocoa.
Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <20220819132756.74641-2-akihiko.odaki@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The qtest/libqos directory is included via the "-I" option to search
for header files when building qtest. Unfortunately the malloc.h has
a name conflict with the standard libc header, leading to a build
failure on the Windows host, due to the MinGW libc stdlib.h header
file includes malloc.h and it now gets wrongly pointed to the one
in the qtest/libqos directory.
Rename "qtest/libqos/malloc.h" to "qtest/libqos/libqos-malloc.h" to
avoid the namespace pollution.
Signed-off-by: Xuzhou Cheng <xuzhou.cheng@windriver.com>
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20220824094029.1634519-26-bmeng.cn@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Windows does not provide a mkdtemp() API, but glib does.
Replace mkdtemp() call with the glib version.
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20220824094029.1634519-3-bmeng.cn@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Windows does not provide a setenv() API, but glib does.
Replace setenv() call with the glib version.
Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20220824094029.1634519-2-bmeng.cn@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
softmmu/datadir.c had its own implementation to find files in the
build tree, but now bundle mechanism provides the unified
implementation which works for datadir and the other files.
Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <20220624145039.49929-4-akihiko.odaki@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Determine the BARs used by the PCI device and register handlers to
manage the access to the same.
Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Signed-off-by: John G Johnson <john.g.johnson@oracle.com>
Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 3373e10b5be5f42846f0632d4382466e1698c505.1655151679.git.jag.raman@oracle.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The function is required by get_relocated_path() (already in cutils),
and used by qemu-ga and may be generally useful.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20220525144140.591926-2-marcandre.lureau@redhat.com>
Header guard symbols should match their file name to make guard
collisions less likely.
Cleaned up with scripts/clean-header-guards.pl, followed by some
renaming of new guard symbols picked by the script to better ones.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20220506134911.2856099-2-armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[Change to generated file ebpf/rss.bpf.skeleton.h backed out]
Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Since commit a2ce7dbd91 ("meson: convert tests/qtest to meson"),
libqtest.h is under libqos/ directory, while libqtest.c is still in
qtest/. Move back to its original location to avoid mixing with libqos/.
Suggested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
../tests/qtest/fuzz/generic_fuzz.c:746:17: warning: variable 'name' set but not used [-Wunused-but-set-variable]
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20220420132624.2439741-42-marcandre.lureau@redhat.com>
Cc: Alexander Oleinik <alxndr@bu.edu>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20211007130829.632254-2-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The timeout mechanism won't work if SIGALRM is blocked. This changes
unmasks SIGALRM when the timer is installed. This doesn't completely
solve the problem, as the fuzzer could trigger some device activity that
re-masks SIGALRM. However, there are currently no inputs on OSS-Fuzz
that re-mask SIGALRM and timeout. If that turns out to be a real issue,
we could try to hook sigmask-type calls, or use a separate timer thread.
Based-on: <20210713150037.9297-1-alxndr@bu.edu>
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Using ITIMER_VIRTUAL is a bad idea, if the fuzzer hits a blocking
syscall - e.g. ppoll with a NULL timespec. This causes timeout issues
while fuzzing some block-device code. Fix that by using wall-clock time.
This might cause inputs to timeout sometimes due to scheduling
effects/ambient load, but it is better than bringing the entire fuzzing
process to a halt.
Based-on: <20210713150037.9297-1-alxndr@bu.edu>
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
We have some configs for devices such as the AC97 and ES1370 that were
not matching memory-regions correctly, because the configs provided
lowercase names. To resolve these problems and prevent them from
occurring again in the future, convert both the pattern and names to
lower-case, prior to checking for a match.
Suggested-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Using a custom timeout is useful to continue fuzzing complex devices,
even after we run into some slow code-path. However, simply adding a
fixed timeout to each input effectively caps the maximum input
length/number of operations at some artificial value. There are two
major problems with this:
1. Some code might only be reachable through long IO sequences.
2. Longer inputs can actually be _better_ for performance. While the
raw number of fuzzer executions decreases with larger inputs, the
number of MMIO/PIO/DMA operation/second actually increases, since
were are speding proportionately less time fork()ing.
With this change, we keep the custom-timeout, but we renew it, prior to
each MMIO/PIO/DMA operation. Thus, we time-out only when a specific
operation takes a long time.
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
The code mistakenly relied on address_space_translate to store the
length remaining until the next memory-region. We care about this
because when there is RAM or sparse-memory neighboring on an MMIO
region, we should only write up to the border, to prevent inadvertently
invoking MMIO handlers within the DMA callback.
However address_space_translate_internal only stores the length until
the end of the MemoryRegion if memory_region_is_ram(mr). Otherwise
the *len is left unmodified. This caused some false-positive issues,
where the fuzzer found a way to perform a nested MMIO write through a
DMA callback on an [address, length] that started within sparse memory
and spanned some device MMIO regions.
To fix this, write to sparse memory in small chunks of
memory_access_size (similar to the underlying address_space_write code),
which will prevent accidentally hitting MMIO handlers through large
writes.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Use memory_region_size() to get the MemoryRegion size,
and display it with the '0x' prefix.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210612195842.1595999-1-f4bug@amsat.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Leading underscores followed by a capital letter or underscore are
reserved by the C standard.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/369
Signed-off-by: Ahmed Abouzied <email@aabouzied.com>
Message-Id: <20210605174938.13782-1-email@aabouzied.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
On Fedora 32, using clang (version 10.0.1-3.fc32) we get:
tests/qtest/fuzz/fuzz.c:237:5: error: implicit declaration of function 'qemu_init' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
qemu_init(result.we_wordc, result.we_wordv, NULL);
^
qemu_init() is declared in "sysemu/sysemu.h", include this
header to fix.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210513162008.3922223-1-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Stop including exec/address-spaces.h in files that don't need it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-5-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Stop including sysemu/sysemu.h in files that don't need it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-2-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The function flatview_for_each_range() calls a callback for each
range in a FlatView. Currently the callback gets the start and
length of the range and the MemoryRegion involved, but not the offset
within the MemoryRegion. Add this to the callback's arguments; we're
going to want it for a new use in the next commit.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210318174823.18066-4-peter.maydell@linaro.org
The return value of the flatview_cb callback passed to the
flatview_for_each_range() function is zero if the iteration through
the ranges should continue, or non-zero to break out of it. Use a
bool for this rather than int.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210318174823.18066-2-peter.maydell@linaro.org
qemu-fuzz-i386-target-generic-fuzz-sdhci-v3 uses -drive=sd where it
should use -drive if=none instead. This prints a deprecation warning:
$ ./build-oss-fuzz/DEST_DIR/qemu-fuzz-i386-target-generic-fuzz-sdhci-v3 -runs=1 -seed=1
[ASan warnings snipped...]
--> i386: -drive if=sd,index=0,file=null-co://,format=raw,id=mydrive: warning: bogus if=sd is deprecated, use if=none
INFO: Seed: 1
[More normal output snipped...]
Support for this usage will be gone soon. Adjust the test.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210319132008.1830950-1-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
The generic-fuzzer often provides randomized DMA addresses to
virtual-devices. For a 64-bit address-space, the chance of these
randomized addresses coinciding with RAM regions, is fairly small. Even
though the fuzzer's instrumentation eventually finds valid addresses,
this can take some-time, and slows-down fuzzing progress (especially,
when multiple DMA buffers are involved). To work around this, create
"fake" sparse-memory that spans all of the 64-bit address-space. Adjust
the DMA call-back to populate this sparse memory, correspondingly
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
I noticed that with a sufficiently small timeout, the fuzzer fork-server
sometimes locks up. On closer inspection, the issue appeared to be
caused by entering our SIGALRM handler, while libfuzzer is in it's crash
handlers. Because libfuzzer relies on pipe communication with an
external child process to print out stack-traces, we shouldn't exit
early, and leave an orphan child. Check for children in the SIGALRM
handler to avoid this issue.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Acked-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The device-type names for the pro100 network cards, are i8255.. We were
matching "eepro", which catches the PCI PIO/MMIO regions for those
devices, however misses the actual PCI device, which we use to map the
BARs, before fuzzing. Fix that
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
virtio-9p devices are often used to expose a virtual-filesystem to the
guest. There have been some bugs reported in this device, such as
CVE-2018-19364, and CVE-2021-20181. We should fuzz this device
This patch adds two virtio-9p configurations:
* One with the widely used -fsdev local driver. This driver leaks some
state in the form of files/directories created in the shared dir.
* One with the synth driver. While it is not used in the real world, this
driver won't leak leak state between fuzz inputs.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20210117230924.449676-4-alxndr@bu.edu>
For some device configurations, it is useful to configure some
resources, and adjust QEMU arguments at runtime, prior to fuzzing. This
patch adds an "argfunc" to generic the generic_fuzz_config. When
specified, it is responsible for configuring the resources and returning
a string containing the corresponding QEMU arguments. This can be useful
for targets that rely on e.g.:
* a temporary qcow2 image
* a temporary directory
* an unused TCP port used to bind the VNC server
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210117230924.449676-2-alxndr@bu.edu>
This is useful for building reproducers. Instead checking the code or
the QEMU_FUZZ_ARGS, the arguments are at the top of the crash log.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210117201014.271610-3-alxndr@bu.edu>
Disks work differently depending on the x86 machine type (SATA vs PATA).
Additionally, we should fuzz the atapi code paths, which might contain
vulnerabilities such as CVE-2020-29443. This patch adds hard-disk and
cdrom generic-fuzzer configs for both the pc (PATA) and q35 (SATA)
machine types.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Acked-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20210120152211.109782-1-alxndr@bu.edu>
We passed an is_write flag to the fuzz_dma_read_cb function to
differentiate between the mapped DMA regions that need to be populated
with fuzzed data, and those that don't. We simply passed through the
address_space_map is_write parameter. The goal was to cut down on
unnecessarily populating mapped DMA regions, when they are not read
from.
Unfortunately, nothing precludes code from reading from regions mapped
with is_write=true. For example, see:
https://lists.gnu.org/archive/html/qemu-devel/2021-01/msg04729.html
This patch removes the is_write parameter to fuzz_dma_read_cb. As a
result, we will fill all mapped DMA regions with fuzzed data, ignoring
the specified transfer direction.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20210120060255.558535-1-alxndr@bu.edu>
Prior to this patch, the fuzzer found inputs to map PCI device BARs and
enable the device. While it is nice that the fuzzer can do this, it
added significant overhead, since the fuzzer needs to map all the
BARs (regenerating the memory topology), at the start of each input.
With this patch, we do this once, before fuzzing, mitigating some of
this overhead.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201221181203.1853-1-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
On the pc-i440fx machine, the floppy drive relies on the i8257 DMA
controller. Add this device to the floppy fuzzer config, and silence the
warning about a missing format specifier for the null-co:// drive.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20201216203328.41112-1-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
