On Friday, 2020-10-23 at 11:07:45 -04, Alexander Bulekov wrote:
> 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
> $DEST_DIR, since oss-fuzz will treat it as an independent fuzzer and try
> to run it for fuzzing. Instead, we create a DEST_DIR/bin directory to
> store the primary copy.
>
> Suggested-by: Darren Kenny <darren.ke...@oracle.com>
> Signed-off-by: Alexander Bulekov <alx...@bu.edu>
Reviewed-by: Darren Kenny <darren.ke...@oracle.com>
> ---
> scripts/oss-fuzz/build.sh | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/scripts/oss-fuzz/build.sh b/scripts/oss-fuzz/build.sh
> index 0c3ca9e06f..0ce2867732 100755
> --- a/scripts/oss-fuzz/build.sh
> +++ b/scripts/oss-fuzz/build.sh
> @@ -62,6 +62,9 @@ fi
>
> mkdir -p "$DEST_DIR/lib/" # Copy the shared libraries here
>
> +mkdir -p "$DEST_DIR/bin/" # Copy executables that shouldn't
> + # be treated as fuzzers by oss-fuzz here
> +
> # Build once to get the list of dynamic lib paths, and copy them over
> ../configure --disable-werror --cc="$CC" --cxx="$CXX" --enable-fuzzing \
> --prefix="$DEST_DIR" --bindir="$DEST_DIR" --datadir="$DEST_DIR/data/" \
> @@ -88,13 +91,16 @@ make "-j$(nproc)" qemu-fuzz-i386 V=1
> # Copy over the datadir
> cp -r ../pc-bios/ "$DEST_DIR/pc-bios"
>
> +cp "./qemu-fuzz-i386" "$DEST_DIR/bin/"
> +
> # Run the fuzzer with no arguments, to print the help-string and get the list
> # of available fuzz-targets. Copy over the qemu-fuzz-i386, naming it
> according
> # to each available fuzz target (See 05509c8e6d fuzz: select fuzz target
> using
> # executable name)
> for target in $(./qemu-fuzz-i386 | awk '$1 ~ /\*/ {print $2}');
> do
> - cp qemu-fuzz-i386 "$DEST_DIR/qemu-fuzz-i386-target-$target"
> + ln "$DEST_DIR/bin/qemu-fuzz-i386" \
> + "$DEST_DIR/qemu-fuzz-i386-target-$target"
> done
>
> echo "Done. The fuzzers are located in $DEST_DIR"
> --
> 2.28.0
