Commit Graph

10 Commits

Author SHA1 Message Date
Alexander Bulekov
53e1a50d6b scripts/oss-fuzz: ignore the generic-fuzz target
generic-fuzz is not a standalone fuzzer - it requires some env variables
to be set. On oss-fuzz, we set these with some predefined
generic-fuzz-{...} targets, that are thin wrappers around generic-fuzz.
Do not make a link for the generic-fuzz from the oss-fuzz build, so
oss-fuzz does not treat it as a standalone fuzzer.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20201023150746.107063-18-alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
[thuth: Reformatted one comment to stay within the 80 columns limit]
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-26 09:53:54 +01:00
Alexander Bulekov
a942f64cc4 scripts/oss-fuzz: use hardlinks instead of copying
Prior to this, fuzzers in the output oss-fuzz directory were exactly
the same executable, with a different name to do argv[0]-based
fuzz-target selection. This is a waste of space, especially since these
binaries can weigh many MB.

Instead of copying, use hard links, to cut down on wasted space. We need
to place the primary copy of the executable into DEST_DIR, since this is
a separate file-system on oss-fuzz. We should not place it directly into
$DEST_DIR, since oss-fuzz will treat it as an independent fuzzer and try
to run it for fuzzing. Instead, we create a DEST_DIR/bin directory to
store the primary copy.

Suggested-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20201023150746.107063-17-alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-26 09:53:54 +01:00
Alexander Bulekov
cd3f0686dd scripts/oss-fuzz: Add crash trace minimization script
Once we find a crash, we can convert it into a QTest trace. Usually this
trace will contain many operations that are unneeded to reproduce the
crash. This script tries to minimize the crashing trace, by removing
operations and trimming QTest bufwrite(write addr len data...) commands.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20201023150746.107063-12-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-26 09:53:53 +01:00
Alexander Bulekov
7c9b64ade9 scripts/oss-fuzz: Add script to reorder a generic-fuzzer trace
The generic-fuzzer uses hooks to fulfill DMA requests just-in-time.
This means that if we try to use QTEST_LOG=1 to build a reproducer, the
DMA writes will be logged _after_ the in/out/read/write that triggered
the DMA read. To work work around this, the generic-fuzzer annotates
these just-in time DMA fulfilments with a tag that we can use to
discern them. This script simply iterates over a raw qtest
trace (including log messages, errors, timestamps etc), filters it and
re-orders it so that DMA fulfillments are placed directly _before_ the
qtest command that will cause the DMA access.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20201023150746.107063-11-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-10-26 09:53:53 +01:00
zhaolichang
65fdb3cc2e scripts/: fix some comment spelling errors
I found that there are many spelling errors in the comments of qemu,
so I used the spellcheck tool to check the spelling errors
and finally found some spelling errors in the scripts folder.

Signed-off-by: zhaolichang <zhaolichang@huawei.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200917075029.313-5-zhaolichang@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-09-17 20:37:55 +02:00
Alexander Bulekov
789035f123 oss-fuzz: fix rpath
Prior to this change,
readelf -d build/out/qemu/qemu-fuzz-i386-target-virtio-net-slirp
...
0x000000000000000f (RPATH)  Library rpath: ['$$ORIGIN/lib':$ORIGIN/migration:$ORIGIN/]

As of 1a4db552d8 ("ninjatool: quote dollars in variables"), we don't
need to manually double the dollars. Also, remove the single-quotes as
they are copied into the rpath.

After this change:
0x000000000000000f (RPATH)  Library rpath: [$ORIGIN/lib:$ORIGIN/migration:$ORIGIN/]

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20200902142657.112879-3-alxndr@bu.edu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-09-08 11:43:16 +02:00
Paolo Bonzini
64ed6f92ff meson: link emulators without Makefile.target
The binaries move to the root directory, e.g. qemu-system-i386 or
qemu-arm.  This requires changes to qtests, CI, etc.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-08-21 06:30:40 -04:00
Paolo Bonzini
77afc75f69 oss-fuzz/build: remove LIB_FUZZING_ENGINE
Meson build scripts will only include qemu-fuzz-TARGET rules if configured
with --enable-fuzzing, and that takes care of adding -fsanitize=fuzzer.
Therefore we can just specify the configure option and stop modifying
the CFLAGS and CONFIG_FUZZ options in the "make" invocation.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-08-21 06:18:22 -04:00
Thomas Huth
7cee363bc2 scripts/oss-fuzz: Limit target list to i386-softmmu
The build.sh script only copies qemu-fuzz-i386 to the destination folder,
so we can speed up the compilation step quite a bit by not compiling the
other targets here.

Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-21 07:21:54 +02:00
Alexander Bulekov
211635b3a2 fuzz: add oss-fuzz build-script
It is neater to keep this in the QEMU repo, since any change that
requires an update to the oss-fuzz build configuration, can make the
necessary changes in the same series.

Suggested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20200612055145.12101-1-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-06-15 18:26:46 +02:00