samba.git/lib/fuzzing, branch talloc-2.3.2

oss-fuzz: Add very verbose explaination for RPATH vs RUNPATH

2020-10-23T00:33:57+00:00

Signed-off-by: Andrew Bartlett 
Reviewed-by: Douglas Bagnall 

Autobuild-User(master): Douglas Bagnall 
Autobuild-Date(master): Fri Oct 23 00:33:57 UTC 2020 on sn-devel-184

oss-fuzz: Always run the check, even on the oss-fuzz platform

2020-10-22T23:08:31+00:00

It is much harder to determine why we get messages like
    Step #6: Error occured while running fuzz_reg_parse:
    Step #6: /workspace/out/coverage/fuzz_reg_parse: error while loading shared libraries: libavahi-common.so.3: cannot open shared object file: No such file or directory
instead this detects the failure to use RPATH (which is
strictly required instead of the modern RUNPATH)
otherwise.

We do this by creating a new build_samba.sh after renaming
build_samba.sh to do_build.sh because this is what oss-fuzz
runs, meaning we don't need to coordinate a MR there as well.

Signed-off-by: Andrew Bartlett 
Reviewed-by: Douglas Bagnall

oss-fuzz: update comment to reference RPATH for the static-ish binaries

2020-10-22T23:08:31+00:00

We strictly require RPATH, so fix the comment to avoid mentioning
the modern RUNPATH which is almost but not entirely similar.

Signed-off-by: Andrew Bartlett 
Reviewed-by: Douglas Bagnall

oss-fuzz: standardise on RPATH for the static-ish binaries

2020-10-22T14:10:04+00:00

This includes a revert of commit e60df214998afc145ca482cab184691b3ddc3bb2.

We strictly require RPATH, not the modern RUNPATH for the behaviour
we need in oss-fuzz, which is that not just the first line of dependencies
but the full set of libraries used by the program are looked for in the
'$ORIGIN/lib' directory.

Signed-off-by: Andrew Bartlett 
Reviewed-by: Douglas Bagnall 

Autobuild-User(master): Douglas Bagnall 
Autobuild-Date(master): Thu Oct 22 14:10:04 UTC 2020 on sn-devel-184

fuzzing: Improve robustness and documentation of the ldd-base library copy

2020-10-22T12:47:37+00:00

This tries to make progress towards understanding why we sometime see errors like
Step #6: Error occured while running fuzz_reg_parse:
Step #6: /workspace/out/coverage/fuzz_reg_parse: error while loading shared libraries: libavahi-common.so.3: cannot open shared object file: No such file or directory

in the previously failing coverage builds.

Signed-off-by: Andrew Bartlett 
Reviewed-by: Douglas Bagnall

fuzzing: Fix the oss-fuzz coverage build

2020-10-21T23:07:37+00:00

It was long thought that the issue here was that no seed corpus was
provided, but actually the issue is that to obtain coverage output
just as we already know for gcc gcov, you must provide fuzzing flags
to both the compile and link phase.

Thankfully clang as a linker does not mind the strange non-linker options
from $COVERAGE_FLAGS.

REF: https://stackoverflow.com/questions/56112019/clang-does-not-generate-profraw-file-when-linking-manually
REF: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=19495#c48

Reviewed-by: Douglas Bagnall 
Signed-off-by: Andrew Bartlett 

Autobuild-User(master): Andrew Bartlett 
Autobuild-Date(master): Wed Oct 21 23:07:37 UTC 2020 on sn-devel-184

fuzz/oss-fuzz/build_samba: fetch fuzz seeds

2020-10-21T03:47:35+00:00

There is a git repository at
https://gitlab.com/samba-team/samba-fuzz-seeds that contains the
seeds. When the master branch of that repository is updated, a CI job
runs that creates a zip file of all the seeds as an artifact. That zip
file is downloaded and unpacked by oss_fuzz/build_samba. The contents
of that zip are further zips that contain the seeds for each fuzzing
binary; these are placed next to the binaries in the manner that
oss-fuzz expects.

That is, beside 'fuzz_foo', we put 'fuzz_foo_seed_corpus.zip' which
contains a pile of fuzz_foo seeds.

There may be times when a new fuzz target does not have a seed corpus,
and times when a removed fuzz target leaves behind a seed corpus.
This is OK, so we don't insist on an exact match between the target
names and the zip names, only that there is some overlap.

Signed-off-by: Douglas Bagnall 
Reviewed-by: Andrew Bartlett 

Autobuild-User(master): Andrew Bartlett 
Autobuild-Date(master): Wed Oct 21 03:47:35 UTC 2020 on sn-devel-184

fuzz/oss-fuzz/build-samba: note the calling site

2020-10-21T02:28:38+00:00

Signed-off-by: Douglas Bagnall 
Reviewed-by: Andrew Bartlett

fuzzing/README: link to wiki

2020-10-21T02:28:38+00:00

Signed-off-by: Douglas Bagnall 
Reviewed-by: Andrew Bartlett

fuzz_dcerpc_parse_binding: don't leak

2020-10-20T02:26:40+00:00

Also, by not tallocing at all in the too-long case, we can short
circuit quicker.

Signed-off-by: Douglas Bagnall 
Reviewed-by: Jeremy Allison 

Autobuild-User(master): Jeremy Allison 
Autobuild-Date(master): Tue Oct 20 02:26:40 UTC 2020 on sn-devel-184