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3 commits

Author SHA1 Message Date
Alban Bedel
89fb6136ad libubox: runqueue: fix use-after-free bug
Fixes a use-after-free bug in runqueue_task_kill():

 Invalid read of size 8
    at runqueue_task_kill (runqueue.c:200)
    by uloop_process_timeouts (uloop.c:505)
    by uloop_run_timeout (uloop.c:542)
    by uloop_run (uloop.h:111)
    by main (tests/test-runqueue.c:126)
  Address 0x5a4b058 is 24 bytes inside a block of size 208 free'd
    at free
    by runqueue_task_complete (runqueue.c:234)
    by runqueue_task_kill (runqueue.c:199)
    by uloop_process_timeouts (uloop.c:505)
    by uloop_run_timeout (uloop.c:542)
    by uloop_run (uloop.h:111)
    by main (tests/test-runqueue.c:126)
  Block was alloc'd at
    at calloc
    by add_sleeper (tests/test-runqueue.c:101)
    by main (tests/test-runqueue.c:123)

Since commit 11e8afea (runqueue should call the complete handler from
more places) the call to the complete() callback has been moved to
runqueue_task_complete().  However in runqueue_task_kill()
runqueue_task_complete() is called before the kill() callback.  This
will result in a use after free if the complete() callback frees the
task struct.

Furthermore runqueue_start_next() is already called at the end of
runqueue_task_complete(), so there is no need to call it again in
runqueue_task_kill().

The issue was that the _complete() callback frees the memory used by the
task struct, which is then read after the _complete() callback returns.

Ref: FS#3016
Signed-off-by: Alban Bedel <albeu@free.fr>
[initial test case, kill cb comment fix]
Signed-off-by: Chris Nisbet <nischris@gmail.com>
[testcase improvements and commit subject/description tweaks]
Signed-off-by: Petr Štetiar <ynezz@true.cz>
2020-05-21 15:58:46 +02:00
Petr Štetiar
bf680707ac tests: add unit tests covered with Clang sanitizers
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>
2019-12-25 10:31:58 +01:00
Petr Štetiar
b0a5cd8a28 add cram based unit tests
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>
2019-11-24 13:26:58 +01:00