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>
Help detecting Valgrind OOB reads and other issues.
Conditional jump or move depends on uninitialised value(s)
at 0x5452886: blobmsg_parse (blobmsg.c:203)
by 0x400A8E: test_blobmsg (tests/test-blobmsg-parse.c:66)
by 0x400A8E: main (tests/test-blobmsg-parse.c:82)
Conditional jump or move depends on uninitialised value(s)
at 0x545247F: blobmsg_check_name (blobmsg.c:39)
by 0x545247F: blobmsg_check_attr_len (blobmsg.c:79)
by 0x5452710: blobmsg_parse_array (blobmsg.c:159)
by 0x400AB8: test_blobmsg (tests/test-blobmsg-parse.c:69)
by 0x400AB8: main (tests/test-blobmsg-parse.c:82)
Conditional jump or move depends on uninitialised value(s)
at 0x54524A0: blobmsg_check_name (blobmsg.c:42)
by 0x54524A0: blobmsg_check_attr_len (blobmsg.c:79)
by 0x5452710: blobmsg_parse_array (blobmsg.c:159)
by 0x400AB8: test_blobmsg (tests/test-blobmsg-parse.c:69)
by 0x400AB8: main (tests/test-blobmsg-parse.c:82)
Ref: http://lists.infradead.org/pipermail/openwrt-devel/2020-January/021204.html
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Better safe than sorry and while at it prefer use of PRId16 and PRId32
formatting constants as well.
Reviewed-by: Jo-Philipp Wich <jo@mein.io>
Signed-off-by: Petr Štetiar <ynezz@true.cz>
libjson-c json_type_int values are stored as int64_t. Use
json_object_get_int64() instead of json_object_get_int()
to avoid clamping to INT32_MAX.
Reviewed-by: Jo-Philipp Wich <jo@mein.io>
Signed-off-by: Dainis Jonitis <dainis.jonitis@ubnt.com>
[fixed author to match SoB, added unit test results]
Signed-off-by: Petr Štetiar <ynezz@true.cz>
int16 blobmsg type is currently being serialized as uint16_t due to
missing cast during JSON output.
Following blobmsg content:
bar-min: -32768 (i16)
bar-max: 32767 (i16)
Produces following JSON:
{ "bar-min":32768,"bar-max":32767 }
Whereas one would expect:
{ "bar-min":-32768,"bar-max":32767 }
Reviewed-by: Jo-Philipp Wich <jo@mein.io>
Signed-off-by: Petr Štetiar <ynezz@true.cz>
* add missing test with sanitizers
* add test case for blobmsg_add_json_from_string
* add test cases for all numeric types
* print types for each variable
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Include shunit2 based tests into unit testing pipeline until
(eventually) it's converted to cram based unit tests.
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Fix incorrect use of blob_raw_len() on passed blobmsg to
blobmsg_check_array_len() introduced in commit b0e21553ae ("blobmsg:
add _len variants for all attribute checking methods") by using correct
blobmsg_len().
This wrong (higher) length was then for example causing issues in
procd's instance_config_parse_command() where blobmsg_check_attr_list()
was failing sanity checking of service command, thus resulting in the
startup failures of some services like collectd, nlbwmon and samba4.
Ref: http://lists.infradead.org/pipermail/openwrt-devel/2019-December/020840.html
Fixes: b0e21553ae ("blobmsg: add _len variants for all attribute checking methods")
Reported-by: Hannu Nyman <hannu.nyman@welho.com>
Tested-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
Signed-off-by: Petr Štetiar <ynezz@true.cz>
==31775==ERROR: AddressSanitizer: SEGV on unknown address 0x604000a7c715
==31775==The signal is caused by a READ memory access.
#0 blobmsg_check_attr blobmsg.c:48:6
#1 blobmsg_parse_array blobmsg.c:118:8
#2 fuzz_blobmsg_parse test-blobmsg-parse-fuzzer.c:35:2
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Found by fuzzer:
ERROR: AddressSanitizer: SEGV on unknown address 0x602100000455
The signal is caused by a READ memory access.
#0 in blob_check_type blob.c:214:43
#1 in blob_parse_attr blob.c:234:9
#2 in blob_parse_untrusted blob.c:272:12
#3 in fuzz_blob_parse tests/fuzzer/test-blob-parse-fuzzer.c:34:2
#4 in LLVMFuzzerTestOneInput tests/fuzzer/test-blob-parse-fuzzer.c:39:2
Caused by following line:
if (type == BLOB_ATTR_STRING && data[len - 1] != 0)
where len was pointing outside of the data buffer.
Signed-off-by: Petr Štetiar <ynezz@true.cz>
==5872==ERROR: AddressSanitizer: SEGV on unknown address 0x6020004100b4
==5872==The signal is caused by a READ memory access.
#0 blob_data blob.h
#1 blob_parse blob.c:228:2
Signed-off-by: Petr Štetiar <ynezz@true.cz>
LibFuzzer is in-process, coverage-guided, evolutionary fuzzing engine.
LibFuzzer is linked with the library under test, and feeds fuzzed inputs
to the library via a specific fuzzing entrypoint (aka "target
function"); the fuzzer then tracks which areas of the code are reached,
and generates mutations on the corpus of input data in order to maximize
the code coverage.
Lets use libFuzzer to fuzz blob and blobmsg parsing for the start.
Ref: https://llvm.org/docs/LibFuzzer.html
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Currently we run all tests via Valgrind. This patch adds 2nd batch of
tests which are compiled with Clang AddressSanitizer[1],
LeakSanitizer[2] and UndefinedBehaviorSanitizer[3] in order to catch
more issues during QA on CI.
AddressSanitizer is a fast memory error detector. The tool can detect
the following types of bugs:
* Out-of-bounds accesses to heap, stack and globals
* Use-after-free, use-after-return, use-after-scope
* Double-free, invalid free
LeakSanitizer is a run-time memory leak detector. It can be combined
with AddressSanitizer to get both memory error and leak detection, or
used in a stand-alone mode.
UndefinedBehaviorSanitizer (UBSan) is a fast undefined behavior
detector. UBSan modifies the program at compile-time to catch various
kinds of undefined behavior during program execution, for example:
* Using misaligned or null pointer
* Signed integer overflow
* Conversion to, from, or between floating-point types which would
overflow the destination
1. http://clang.llvm.org/docs/AddressSanitizer.html
2. http://http://clang.llvm.org/docs/LeakSanitizer.html
3. http://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html
Signed-off-by: Petr Štetiar <ynezz@true.cz>
Add missing usage hints for -p and -o arguments.
Fixes: e16fa068a5 ("jshn: add support for namespaces")
Fixes: eb30a03048 ("libubox, jshn: add option to write output to a file")
Signed-off-by: Petr Štetiar <ynezz@true.cz>
clang-10 analyzer reports following:
base64.c:325:20: warning: Array access (from variable 'target') results in a null pointer dereference
target[tarindex] = 0;
~~~~~~ ^
and prepared test case confirms it:
Invalid write of size 1
at 0x4E4463F: b64_decode (base64.c:325)
by 0x40088C: test_invalid_inputs (tests/test-base64.c:26)
by 0x40088C: main (tests/test-base64.c:32)
Address 0x1 is not stack'd, malloc'd or (recently) free'd
Process terminating with default action of signal 11 (SIGSEGV)
Access not within mapped region at address 0x1
at 0x4E4463F: b64_decode (base64.c:325)
by 0x40088C: test_invalid_inputs (tests/test-base64.c:26)
by 0x40088C: main (tests/test-base64.c:32)
Signed-off-by: Petr Štetiar <ynezz@true.cz>
For improved QA etc. For the start with initial test cases for avl,
base64, jshn and list components. Moved runqueue and blobmsg from
examples to tests. Converted just a few first test cases from
json-script example into the new cram based unit test, more to come.
Signed-off-by: Petr Štetiar <ynezz@true.cz>
