Merge tag 'io_uring-5.12-2021-03-21' of git://git.kernel.dk/linux-block
Pull io_uring followup fixes from Jens Axboe:
- The SIGSTOP change from Eric, so we properly ignore that for
PF_IO_WORKER threads.
- Disallow sending signals to PF_IO_WORKER threads in general, we're
not interested in having them funnel back to the io_uring owning
task.
- Stable fix from Stefan, ensuring we properly break links for short
send/sendmsg recv/recvmsg if MSG_WAITALL is set.
- Catch and loop when needing to run task_work before a PF_IO_WORKER
threads goes to sleep.
* tag 'io_uring-5.12-2021-03-21' of git://git.kernel.dk/linux-block:
io_uring: call req_set_fail_links() on short send[msg]()/recv[msg]() with MSG_WAITALL
io-wq: ensure task is running before processing task_work
signal: don't allow STOP on PF_IO_WORKER threads
signal: don't allow sending any signals to PF_IO_WORKER threads
diff --git a/fs/io-wq.c b/fs/io-wq.c
index e05f996..3dc10bf 100644
--- a/fs/io-wq.c
+++ b/fs/io-wq.c
@@ -386,13 +386,16 @@
return NULL;
}
-static void io_flush_signals(void)
+static bool io_flush_signals(void)
{
if (unlikely(test_tsk_thread_flag(current, TIF_NOTIFY_SIGNAL))) {
+ __set_current_state(TASK_RUNNING);
if (current->task_works)
task_work_run();
clear_tsk_thread_flag(current, TIF_NOTIFY_SIGNAL);
+ return true;
}
+ return false;
}
static void io_assign_current_work(struct io_worker *worker,
@@ -499,7 +502,8 @@
}
__io_worker_idle(wqe, worker);
raw_spin_unlock_irq(&wqe->lock);
- io_flush_signals();
+ if (io_flush_signals())
+ continue;
ret = schedule_timeout(WORKER_IDLE_TIMEOUT);
if (try_to_freeze() || ret)
continue;
diff --git a/fs/io_uring.c b/fs/io_uring.c
index ea2d3e1..543551d 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -4386,6 +4386,7 @@
struct io_async_msghdr iomsg, *kmsg;
struct socket *sock;
unsigned flags;
+ int min_ret = 0;
int ret;
sock = sock_from_file(req->file);
@@ -4406,6 +4407,9 @@
else if (issue_flags & IO_URING_F_NONBLOCK)
flags |= MSG_DONTWAIT;
+ if (flags & MSG_WAITALL)
+ min_ret = iov_iter_count(&kmsg->msg.msg_iter);
+
ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
return io_setup_async_msg(req, kmsg);
@@ -4416,7 +4420,7 @@
if (kmsg->free_iov)
kfree(kmsg->free_iov);
req->flags &= ~REQ_F_NEED_CLEANUP;
- if (ret < 0)
+ if (ret < min_ret)
req_set_fail_links(req);
__io_req_complete(req, issue_flags, ret, 0);
return 0;
@@ -4429,6 +4433,7 @@
struct iovec iov;
struct socket *sock;
unsigned flags;
+ int min_ret = 0;
int ret;
sock = sock_from_file(req->file);
@@ -4450,6 +4455,9 @@
else if (issue_flags & IO_URING_F_NONBLOCK)
flags |= MSG_DONTWAIT;
+ if (flags & MSG_WAITALL)
+ min_ret = iov_iter_count(&msg.msg_iter);
+
msg.msg_flags = flags;
ret = sock_sendmsg(sock, &msg);
if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
@@ -4457,7 +4465,7 @@
if (ret == -ERESTARTSYS)
ret = -EINTR;
- if (ret < 0)
+ if (ret < min_ret)
req_set_fail_links(req);
__io_req_complete(req, issue_flags, ret, 0);
return 0;
@@ -4609,6 +4617,7 @@
struct socket *sock;
struct io_buffer *kbuf;
unsigned flags;
+ int min_ret = 0;
int ret, cflags = 0;
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
@@ -4640,6 +4649,9 @@
else if (force_nonblock)
flags |= MSG_DONTWAIT;
+ if (flags & MSG_WAITALL)
+ min_ret = iov_iter_count(&kmsg->msg.msg_iter);
+
ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg,
kmsg->uaddr, flags);
if (force_nonblock && ret == -EAGAIN)
@@ -4653,7 +4665,7 @@
if (kmsg->free_iov)
kfree(kmsg->free_iov);
req->flags &= ~REQ_F_NEED_CLEANUP;
- if (ret < 0)
+ if (ret < min_ret || ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
req_set_fail_links(req);
__io_req_complete(req, issue_flags, ret, cflags);
return 0;
@@ -4668,6 +4680,7 @@
struct socket *sock;
struct iovec iov;
unsigned flags;
+ int min_ret = 0;
int ret, cflags = 0;
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
@@ -4699,6 +4712,9 @@
else if (force_nonblock)
flags |= MSG_DONTWAIT;
+ if (flags & MSG_WAITALL)
+ min_ret = iov_iter_count(&msg.msg_iter);
+
ret = sock_recvmsg(sock, &msg, flags);
if (force_nonblock && ret == -EAGAIN)
return -EAGAIN;
@@ -4707,7 +4723,7 @@
out_free:
if (req->flags & REQ_F_BUFFER_SELECTED)
cflags = io_put_recv_kbuf(req);
- if (ret < 0)
+ if (ret < min_ret || ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
req_set_fail_links(req);
__io_req_complete(req, issue_flags, ret, cflags);
return 0;
diff --git a/kernel/signal.c b/kernel/signal.c
index ba4d1ef..f2a1b89 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -288,7 +288,8 @@
JOBCTL_STOP_SIGMASK | JOBCTL_TRAPPING));
BUG_ON((mask & JOBCTL_TRAPPING) && !(mask & JOBCTL_PENDING_MASK));
- if (unlikely(fatal_signal_pending(task) || (task->flags & PF_EXITING)))
+ if (unlikely(fatal_signal_pending(task) ||
+ (task->flags & (PF_EXITING | PF_IO_WORKER))))
return false;
if (mask & JOBCTL_STOP_SIGMASK)
@@ -833,6 +834,9 @@
if (!valid_signal(sig))
return -EINVAL;
+ /* PF_IO_WORKER threads don't take any signals */
+ if (t->flags & PF_IO_WORKER)
+ return -ESRCH;
if (!si_fromuser(info))
return 0;
