Using ITIMER_VIRTUAL is a bad idea, if the fuzzer hits a blocking
syscall - e.g. ppoll with a NULL timespec. This causes timeout issues
while fuzzing some block-device code. Fix that by using wall-clock time.
This might cause inputs to timeout sometimes due to scheduling
effects/ambient load, but it is better than bringing the entire fuzzing
process to a halt.
Based-on: <20210713150037.9297-1-alx...@bu.edu>
Signed-off-by: Alexander Bulekov <alx...@bu.edu>
Reviewed-by: Darren Kenny <darren.ke...@oracle.com>
---
tests/qtest/fuzz/generic_fuzz.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tests/qtest/fuzz/generic_fuzz.c b/tests/qtest/fuzz/generic_fuzz.c
index 3e8ce29227..de427a3727 100644
--- a/tests/qtest/fuzz/generic_fuzz.c
+++ b/tests/qtest/fuzz/generic_fuzz.c
@@ -695,7 +695,7 @@ static void generic_fuzz(QTestState *s, const unsigned char
*Data, size_t Size)
while (cmd && Size) {
/* Reset the timeout, each time we run a new command */
if (timeout) {
- setitimer(ITIMER_VIRTUAL, &timer, NULL);
+ setitimer(ITIMER_REAL, &timer, NULL);
}
/* Get the length until the next command or end of input */
--
2.30.2
