aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMark Johnston <markj@FreeBSD.org>2021-07-16 02:38:46 +0000
committerMark Johnston <markj@FreeBSD.org>2021-07-30 00:32:58 +0000
commit9ac0aec3a32c84599cfbcc9f70ca2e035a3ddc0b (patch)
treeeda7cc6dcd5423800854c823e2cf98b5a5d8d925
parent24c558ca3c04e23681ddefe13d0cd5f98bba9fac (diff)
downloadsrc-9ac0aec3a32c84599cfbcc9f70ca2e035a3ddc0b.tar.gz
src-9ac0aec3a32c84599cfbcc9f70ca2e035a3ddc0b.zip
lio_listio: Don't post a completion notification if none was requested
One is allowed to use LIO_NOWAIT without specifying a sigevent. In this case, lj->lioj_signal is left uninitialized, but several code paths examine liov_signal.sigev_notify to figure out which notification to post. Unconditionally initialize that field to SIGEV_NONE. Add a dumb test case which triggers the bug. Reported by: KMSAN+syzkaller Reviewed by: asomers Sponsored by: The FreeBSD Foundation (cherry picked from commit 2e5f6152952e4cfbaab3d96368c3dc4218786632)
-rw-r--r--sys/kern/vfs_aio.c1
-rw-r--r--tests/sys/aio/lio_test.c10
2 files changed, 11 insertions, 0 deletions
diff --git a/sys/kern/vfs_aio.c b/sys/kern/vfs_aio.c
index 640e82b6f0ff..7d4d9ac3e94b 100644
--- a/sys/kern/vfs_aio.c
+++ b/sys/kern/vfs_aio.c
@@ -2246,6 +2246,7 @@ kern_lio_listio(struct thread *td, int mode, struct aiocb * const *uacb_list,
lj->lioj_flags = 0;
lj->lioj_count = 0;
lj->lioj_finished_count = 0;
+ lj->lioj_signal.sigev_notify = SIGEV_NONE;
knlist_init_mtx(&lj->klist, AIO_MTX(ki));
ksiginfo_init(&lj->lioj_ksi);
diff --git a/tests/sys/aio/lio_test.c b/tests/sys/aio/lio_test.c
index fb519aac978d..a4f5a6a38632 100644
--- a/tests/sys/aio/lio_test.c
+++ b/tests/sys/aio/lio_test.c
@@ -133,6 +133,15 @@ ATF_TC_BODY(lio_listio_empty_wait, tc)
ATF_REQUIRE_EQ(0, lio_listio(LIO_WAIT, &list, 0, NULL));
}
+/* With LIO_NOWAIT, an empty lio_listio should return immediately */
+ATF_TC_WITHOUT_HEAD(lio_listio_empty_nowait);
+ATF_TC_BODY(lio_listio_empty_nowait, tc)
+{
+ struct aiocb *list = NULL;
+
+ ATF_REQUIRE_EQ(0, lio_listio(LIO_NOWAIT, &list, 0, NULL));
+}
+
/*
* With LIO_NOWAIT, an empty lio_listio should send completion notification
* immediately
@@ -253,6 +262,7 @@ ATF_TP_ADD_TCS(tp)
{
ATF_TP_ADD_TC(tp, lio_listio_eagain_kevent);
+ ATF_TP_ADD_TC(tp, lio_listio_empty_nowait);
ATF_TP_ADD_TC(tp, lio_listio_empty_nowait_kevent);
ATF_TP_ADD_TC(tp, lio_listio_empty_nowait_signal);
ATF_TP_ADD_TC(tp, lio_listio_empty_nowait_thread);