libubox/tests/cram/test_blob_parse.t
Juraj Vijtiuk 43a103ff17 blobmsg: blobmsg_parse and blobmsg_parse_array oob read fixes
Fix out of bounds read in blobmsg_parse and blobmsg_check_name. The
out of bounds read happens because blob_attr and blobmsg_hdr have
flexible array members, whose size is 0 in the corresponding sizeofs.
For example the __blob_for_each_attr macro checks whether rem >=
sizeof(struct blob_attr). However, what LibFuzzer discovered was,
if the input data was only 4 bytes, the data would be casted to blob_attr,
and later on blob_data(attr) would be called even though attr->data was empty.
The same issue could appear with data larger than 4 bytes, where data
wasn't empty, but contained only the start of the blobmsg_hdr struct,
and blobmsg_hdr name was empty. The bugs were discovered by fuzzing
blobmsg_parse and blobmsg_array_parse with LibFuzzer.

CC: Luka Perkov <luka.perkov@sartura.hr>
Reviewed-by: Jo-Philipp Wich <jo@mein.io>
Signed-off-by: Juraj Vijtiuk <juraj.vijtiuk@sartura.hr>
[refactored some checks, added fuzz inputs, adjusted unit test results]
Signed-off-by: Petr Štetiar <ynezz@true.cz>
2020-01-20 16:54:10 +01:00

82 lines
3.6 KiB
Perl

check that blob_parse is producing expected results:
$ [ -n "$TEST_BIN_DIR" ] && export PATH="$TEST_BIN_DIR:$PATH"
$ export TEST_INPUTS="$TESTDIR/inputs"
$ export FUZZ_CORPUS="$TESTDIR/../fuzz/corpus"
$ valgrind --quiet --leak-check=full test-blob-parse $TEST_INPUTS/key-build.ucert
=== CHAIN ELEMENT 01 ===
signature:
---
untrusted comment: signed by key 84bfc88a17166577
RWSEv8iKFxZld+bQ+NTqCdDlHOuVYNw5Qw7Q8shjfMgFJcTqrzaqO0bysjIQhTadmcwvWiWvHlyMcwAXSix2BYdfghz/zhDjvgU=
---
payload:
---
"ucert": {
\t"certtype": 1, (esc)
\t"validfrom": 1546188410, (esc)
\t"expiresat": 1577724410, (esc)
\t"pubkey": "untrusted comment: Local build key\\nRWSEv8iKFxZld6vicE1icWhYNfEV9PM7C9MKUKl+YNEKB+PdAWGDF5Z9\\n" (esc)
}
---
$ valgrind --quiet --leak-check=full test-blob-parse $TEST_INPUTS/invalid.ucert
cannot parse cert invalid.ucert
$ test-blob-parse-san $TEST_INPUTS/key-build.ucert
=== CHAIN ELEMENT 01 ===
signature:
---
untrusted comment: signed by key 84bfc88a17166577
RWSEv8iKFxZld+bQ+NTqCdDlHOuVYNw5Qw7Q8shjfMgFJcTqrzaqO0bysjIQhTadmcwvWiWvHlyMcwAXSix2BYdfghz/zhDjvgU=
---
payload:
---
"ucert": {
\t"certtype": 1, (esc)
\t"validfrom": 1546188410, (esc)
\t"expiresat": 1577724410, (esc)
\t"pubkey": "untrusted comment: Local build key\\nRWSEv8iKFxZld6vicE1icWhYNfEV9PM7C9MKUKl+YNEKB+PdAWGDF5Z9\\n" (esc)
}
---
$ test-blob-parse-san $TEST_INPUTS/invalid.ucert
cannot parse cert invalid.ucert
$ for blob in $(LC_ALL=C find $FUZZ_CORPUS -type f | sort ); do
> valgrind --quiet --leak-check=full test-blob-parse $blob; \
> test-blob-parse-san $blob; \
> done
cannot parse cert 71520a5c4b5ca73903216857abbad54a8002d44a
cannot parse cert 71520a5c4b5ca73903216857abbad54a8002d44a
cannot parse cert c1dfd96eea8cc2b62785275bca38ac261256e278
cannot parse cert c1dfd96eea8cc2b62785275bca38ac261256e278
cannot parse cert c42ac1c46f1d4e211c735cc7dfad4ff8391110e9
cannot parse cert c42ac1c46f1d4e211c735cc7dfad4ff8391110e9
cannot parse cert crash-1b8fb1be45db3aff7699100f497fb74138f3df4f
cannot parse cert crash-1b8fb1be45db3aff7699100f497fb74138f3df4f
cannot parse cert crash-333757b203a44751d3535f24b05f467183a96d09
cannot parse cert crash-333757b203a44751d3535f24b05f467183a96d09
cannot parse cert crash-4c4d2c3c9ade5da9347534e290305c3b9760f627
cannot parse cert crash-4c4d2c3c9ade5da9347534e290305c3b9760f627
cannot parse cert crash-5e9937b197c88bf4e7b7ee2612456cad4cb83f5b
cannot parse cert crash-5e9937b197c88bf4e7b7ee2612456cad4cb83f5b
cannot parse cert crash-75b146c4e6fac64d3e62236b27c64b50657bab2a
cannot parse cert crash-75b146c4e6fac64d3e62236b27c64b50657bab2a
cannot parse cert crash-813f3e68661da09c26d4a87dbb9d5099e92be50f
cannot parse cert crash-813f3e68661da09c26d4a87dbb9d5099e92be50f
cannot parse cert crash-98595faa58ba01d85ba4fd0b109cd3d490b45795
cannot parse cert crash-98595faa58ba01d85ba4fd0b109cd3d490b45795
cannot parse cert crash-a3585b70f1c7ffbdec10f6dadc964336118485c4
cannot parse cert crash-a3585b70f1c7ffbdec10f6dadc964336118485c4
cannot parse cert crash-b3585b70f1c7ffbdec10f6dadc964336118485c4
cannot parse cert crash-b3585b70f1c7ffbdec10f6dadc964336118485c4
cannot parse cert crash-d0f3aa7d60a094b021f635d4edb7807c055a4ea1
cannot parse cert crash-d0f3aa7d60a094b021f635d4edb7807c055a4ea1
cannot parse cert crash-df9d1243057b27bbad6211e5a23d1cb699028aa2
cannot parse cert crash-df9d1243057b27bbad6211e5a23d1cb699028aa2
cannot parse cert crash-e2fd5ecb3b37926743256f1083f47a07c39e10c2
cannot parse cert crash-e2fd5ecb3b37926743256f1083f47a07c39e10c2
cannot parse cert valid-blobmsg.bin
cannot parse cert valid-blobmsg.bin