diff mbox series

[v6,16/16] scripts/oss-fuzz: remove the generic-fuzz target

Message ID 20201021210922.572955-17-alxndr@bu.edu
State Superseded
Headers show
Series Add a Generic Virtual Device Fuzzer | expand

Commit Message

Alexander Bulekov Oct. 21, 2020, 9:09 p.m. UTC
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.
Remove 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>
---
 scripts/oss-fuzz/build.sh | 6 ++++++
 1 file changed, 6 insertions(+)

Comments

Darren Kenny Oct. 22, 2020, 9:32 a.m. UTC | #1
Hi Alex,

On Wednesday, 2020-10-21 at 17:09:22 -04, Alexander Bulekov wrote:
> 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.
> Remove 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>
> ---
>  scripts/oss-fuzz/build.sh | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/scripts/oss-fuzz/build.sh b/scripts/oss-fuzz/build.sh
> index 0c3ca9e06f..37cd7f9e25 100755
> --- a/scripts/oss-fuzz/build.sh
> +++ b/scripts/oss-fuzz/build.sh
> @@ -97,5 +97,11 @@ do

I'm presuming that the target that you're removing is being created by
this line, maybe we should just specifically skip it here instead?

The comment below on the removal probably would still apply though.

>      cp qemu-fuzz-i386 "$DEST_DIR/qemu-fuzz-i386-target-$target"

Also, did you look into using hard-links, or even sym-links - they would
require less duplication of the binaries, which may be important, or may
not, and quicker creation too, e.g.

      ln qemu-fuzz-i386 "$DEST_DIR/qemu-fuzz-i386-target-$target"

It's something that has been done for years, for example if you do:

      ls -il /sbin/{e2fsck,fsck.ext*}

you will see they share the same inode. Similarly for vi and ex, they
use symlinks (hardlinks on some OSes, but seems not Linux):

      ls -il /bin/{vi,ex}

The main point is that argv[0] will be the name of link itself, not the
thing pointed to.

Thanks,

Darren.

>  done
>  
> +# Remove the generic-fuzz target, as it requires some environment variables to
> +# be configured. We have some generic-fuzz-{pc-q35, floppy, ...} targets that
> +# are thin wrappers around this target that set the required environment
> +# variables according to predefined configs.
> +rm "$DEST_DIR/qemu-fuzz-i386-target-generic-fuzz"
> +
>  echo "Done. The fuzzers are located in $DEST_DIR"
>  exit 0
> -- 
> 2.28.0
Alexander Bulekov Oct. 22, 2020, 1:01 p.m. UTC | #2
On 201022 1032, Darren Kenny wrote:
> Hi Alex,

> 

> On Wednesday, 2020-10-21 at 17:09:22 -04, Alexander Bulekov wrote:

> > 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.

> > Remove 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>

> > ---

> >  scripts/oss-fuzz/build.sh | 6 ++++++

> >  1 file changed, 6 insertions(+)

> >

> > diff --git a/scripts/oss-fuzz/build.sh b/scripts/oss-fuzz/build.sh

> > index 0c3ca9e06f..37cd7f9e25 100755

> > --- a/scripts/oss-fuzz/build.sh

> > +++ b/scripts/oss-fuzz/build.sh

> > @@ -97,5 +97,11 @@ do

> 


Hi Darren,

> I'm presuming that the target that you're removing is being created by

> this line, maybe we should just specifically skip it here instead?


Sounds good.

> The comment below on the removal probably would still apply though.

> 

> >      cp qemu-fuzz-i386 "$DEST_DIR/qemu-fuzz-i386-target-$target"

> 

> Also, did you look into using hard-links, or even sym-links - they would

> require less duplication of the binaries, which may be important, or may

> not, and quicker creation too, e.g.

> 

>       ln qemu-fuzz-i386 "$DEST_DIR/qemu-fuzz-i386-target-$target"


This is what I tried, when I was putting together the patch-series, and
it raised an error when I was testing it in the oss-fuzz
docker-containers. I blamed it on Docker, originally, but I just took a
closer look, and the problem was that "qemu-fuzz-i386" isn't on the same
file-system as $DEST_DIR in the oss-fuzz Docker. If I copy
qemu-fuzz-i386 to $DEST_DIR/lib, and do 
    ln "$DEST_DIR/lib/qemu-fuzz-i386" \
       "$DEST_DIR/qemu-fuzz-i386-target-$target"
everything works :)
Thanks
-Alex

> 

> It's something that has been done for years, for example if you do:

> 

>       ls -il /sbin/{e2fsck,fsck.ext*}

> 

> you will see they share the same inode. Similarly for vi and ex, they

> use symlinks (hardlinks on some OSes, but seems not Linux):

> 

>       ls -il /bin/{vi,ex}

> 

> The main point is that argv[0] will be the name of link itself, not the

> thing pointed to.

> 

> Thanks,

> 

> Darren.

> 

> >  done

> >  

> > +# Remove the generic-fuzz target, as it requires some environment variables to

> > +# be configured. We have some generic-fuzz-{pc-q35, floppy, ...} targets that

> > +# are thin wrappers around this target that set the required environment

> > +# variables according to predefined configs.

> > +rm "$DEST_DIR/qemu-fuzz-i386-target-generic-fuzz"

> > +

> >  echo "Done. The fuzzers are located in $DEST_DIR"

> >  exit 0

> > -- 

> > 2.28.0
Darren Kenny Oct. 22, 2020, 1:13 p.m. UTC | #3
On Thursday, 2020-10-22 at 09:01:23 -04, Alexander Bulekov wrote:
> On 201022 1032, Darren Kenny wrote:
>> Hi Alex,
>> 
>> On Wednesday, 2020-10-21 at 17:09:22 -04, Alexander Bulekov wrote:
>> > 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.
>> > Remove 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>
>> > ---
>> >  scripts/oss-fuzz/build.sh | 6 ++++++
>> >  1 file changed, 6 insertions(+)
>> >
>> > diff --git a/scripts/oss-fuzz/build.sh b/scripts/oss-fuzz/build.sh
>> > index 0c3ca9e06f..37cd7f9e25 100755
>> > --- a/scripts/oss-fuzz/build.sh
>> > +++ b/scripts/oss-fuzz/build.sh
>> > @@ -97,5 +97,11 @@ do
>> 
>
> Hi Darren,
>
>> I'm presuming that the target that you're removing is being created by
>> this line, maybe we should just specifically skip it here instead?
>
> Sounds good.
>
>> The comment below on the removal probably would still apply though.
>> 
>> >      cp qemu-fuzz-i386 "$DEST_DIR/qemu-fuzz-i386-target-$target"
>> 
>> Also, did you look into using hard-links, or even sym-links - they would
>> require less duplication of the binaries, which may be important, or may
>> not, and quicker creation too, e.g.
>> 
>>       ln qemu-fuzz-i386 "$DEST_DIR/qemu-fuzz-i386-target-$target"
>
> This is what I tried, when I was putting together the patch-series, and
> it raised an error when I was testing it in the oss-fuzz
> docker-containers. I blamed it on Docker, originally, but I just took a
> closer look, and the problem was that "qemu-fuzz-i386" isn't on the same
> file-system as $DEST_DIR in the oss-fuzz Docker. If I copy
> qemu-fuzz-i386 to $DEST_DIR/lib, and do 
>     ln "$DEST_DIR/lib/qemu-fuzz-i386" \
>        "$DEST_DIR/qemu-fuzz-i386-target-$target"
> everything works :)

Fair enough then!

Thanks,

Darren.

> Thanks
> -Alex
>
>> 
>> It's something that has been done for years, for example if you do:
>> 
>>       ls -il /sbin/{e2fsck,fsck.ext*}
>> 
>> you will see they share the same inode. Similarly for vi and ex, they
>> use symlinks (hardlinks on some OSes, but seems not Linux):
>> 
>>       ls -il /bin/{vi,ex}
>> 
>> The main point is that argv[0] will be the name of link itself, not the
>> thing pointed to.
>> 
>> Thanks,
>> 
>> Darren.
>> 
>> >  done
>> >  
>> > +# Remove the generic-fuzz target, as it requires some environment variables to
>> > +# be configured. We have some generic-fuzz-{pc-q35, floppy, ...} targets that
>> > +# are thin wrappers around this target that set the required environment
>> > +# variables according to predefined configs.
>> > +rm "$DEST_DIR/qemu-fuzz-i386-target-generic-fuzz"
>> > +
>> >  echo "Done. The fuzzers are located in $DEST_DIR"
>> >  exit 0
>> > -- 
>> > 2.28.0
diff mbox series

Patch

diff --git a/scripts/oss-fuzz/build.sh b/scripts/oss-fuzz/build.sh
index 0c3ca9e06f..37cd7f9e25 100755
--- a/scripts/oss-fuzz/build.sh
+++ b/scripts/oss-fuzz/build.sh
@@ -97,5 +97,11 @@  do
     cp qemu-fuzz-i386 "$DEST_DIR/qemu-fuzz-i386-target-$target"
 done
 
+# Remove the generic-fuzz target, as it requires some environment variables to
+# be configured. We have some generic-fuzz-{pc-q35, floppy, ...} targets that
+# are thin wrappers around this target that set the required environment
+# variables according to predefined configs.
+rm "$DEST_DIR/qemu-fuzz-i386-target-generic-fuzz"
+
 echo "Done. The fuzzers are located in $DEST_DIR"
 exit 0