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-rw-r--r--io_uring/eventfd.c10
-rw-r--r--io_uring/io_uring.c26
-rw-r--r--io_uring/kbuf.c13
-rw-r--r--io_uring/net.c2
-rw-r--r--io_uring/register.c12
-rw-r--r--io_uring/zcrx.c5
6 files changed, 58 insertions, 10 deletions
diff --git a/io_uring/eventfd.c b/io_uring/eventfd.c
index 78f8ab7db104..ab789e1ebe91 100644
--- a/io_uring/eventfd.c
+++ b/io_uring/eventfd.c
@@ -76,11 +76,15 @@ void io_eventfd_signal(struct io_ring_ctx *ctx, bool cqe_event)
{
bool skip = false;
struct io_ev_fd *ev_fd;
-
- if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
- return;
+ struct io_rings *rings;
guard(rcu)();
+
+ rings = rcu_dereference(ctx->rings_rcu);
+ if (!rings)
+ return;
+ if (READ_ONCE(rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
+ return;
ev_fd = rcu_dereference(ctx->io_ev_fd);
/*
* Check again if ev_fd exists in case an io_eventfd_unregister call
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 63efd60829f3..ac1a5cf10287 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -1202,6 +1202,21 @@ void tctx_task_work(struct callback_head *cb)
WARN_ON_ONCE(ret);
}
+/*
+ * Sets IORING_SQ_TASKRUN in the sq_flags shared with userspace, using the
+ * RCU protected rings pointer to be safe against concurrent ring resizing.
+ */
+static void io_ctx_mark_taskrun(struct io_ring_ctx *ctx)
+{
+ lockdep_assert_in_rcu_read_lock();
+
+ if (ctx->flags & IORING_SETUP_TASKRUN_FLAG) {
+ struct io_rings *rings = rcu_dereference(ctx->rings_rcu);
+
+ atomic_or(IORING_SQ_TASKRUN, &rings->sq_flags);
+ }
+}
+
static void io_req_local_work_add(struct io_kiocb *req, unsigned flags)
{
struct io_ring_ctx *ctx = req->ctx;
@@ -1256,8 +1271,7 @@ static void io_req_local_work_add(struct io_kiocb *req, unsigned flags)
*/
if (!head) {
- if (ctx->flags & IORING_SETUP_TASKRUN_FLAG)
- atomic_or(IORING_SQ_TASKRUN, &ctx->rings->sq_flags);
+ io_ctx_mark_taskrun(ctx);
if (ctx->has_evfd)
io_eventfd_signal(ctx, false);
}
@@ -1281,6 +1295,10 @@ static void io_req_normal_work_add(struct io_kiocb *req)
if (!llist_add(&req->io_task_work.node, &tctx->task_list))
return;
+ /*
+ * Doesn't need to use ->rings_rcu, as resizing isn't supported for
+ * !DEFER_TASKRUN.
+ */
if (ctx->flags & IORING_SETUP_TASKRUN_FLAG)
atomic_or(IORING_SQ_TASKRUN, &ctx->rings->sq_flags);
@@ -2152,7 +2170,7 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
* well as 2 contiguous entries.
*/
if (!(ctx->flags & IORING_SETUP_SQE_MIXED) || *left < 2 ||
- !(ctx->cached_sq_head & (ctx->sq_entries - 1)))
+ (unsigned)(sqe - ctx->sq_sqes) >= ctx->sq_entries - 1)
return io_init_fail_req(req, -EINVAL);
/*
* A 128b operation on a mixed SQ uses two entries, so we have
@@ -2760,6 +2778,7 @@ static void io_rings_free(struct io_ring_ctx *ctx)
io_free_region(ctx->user, &ctx->sq_region);
io_free_region(ctx->user, &ctx->ring_region);
ctx->rings = NULL;
+ RCU_INIT_POINTER(ctx->rings_rcu, NULL);
ctx->sq_sqes = NULL;
}
@@ -3389,6 +3408,7 @@ static __cold int io_allocate_scq_urings(struct io_ring_ctx *ctx,
if (ret)
return ret;
ctx->rings = rings = io_region_get_ptr(&ctx->ring_region);
+ rcu_assign_pointer(ctx->rings_rcu, rings);
if (!(ctx->flags & IORING_SETUP_NO_SQARRAY))
ctx->sq_array = (u32 *)((char *)rings + rl->sq_array_offset);
diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c
index dae5b4ab3819..e7f444953dfb 100644
--- a/io_uring/kbuf.c
+++ b/io_uring/kbuf.c
@@ -111,9 +111,18 @@ bool io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags)
buf = req->kbuf;
bl = io_buffer_get_list(ctx, buf->bgid);
- list_add(&buf->list, &bl->buf_list);
- bl->nbufs++;
+ /*
+ * If the buffer list was upgraded to a ring-based one, or removed,
+ * while the request was in-flight in io-wq, drop it.
+ */
+ if (bl && !(bl->flags & IOBL_BUF_RING)) {
+ list_add(&buf->list, &bl->buf_list);
+ bl->nbufs++;
+ } else {
+ kfree(buf);
+ }
req->flags &= ~REQ_F_BUFFER_SELECTED;
+ req->kbuf = NULL;
io_ring_submit_unlock(ctx, issue_flags);
return true;
diff --git a/io_uring/net.c b/io_uring/net.c
index d9a4b83804a2..cfcd49f0cecf 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -375,6 +375,8 @@ static int io_send_setup(struct io_kiocb *req, const struct io_uring_sqe *sqe)
kmsg->msg.msg_namelen = addr_len;
}
if (sr->flags & IORING_RECVSEND_FIXED_BUF) {
+ if (sr->flags & IORING_SEND_VECTORIZED)
+ return -EINVAL;
req->flags |= REQ_F_IMPORT_BUFFER;
return 0;
}
diff --git a/io_uring/register.c b/io_uring/register.c
index 12318c276068..ff9d75ffbd15 100644
--- a/io_uring/register.c
+++ b/io_uring/register.c
@@ -545,7 +545,15 @@ overflow:
ctx->sq_entries = p->sq_entries;
ctx->cq_entries = p->cq_entries;
+ /*
+ * Just mark any flag we may have missed and that the application
+ * should act on unconditionally. Worst case it'll be an extra
+ * syscall.
+ */
+ atomic_or(IORING_SQ_TASKRUN | IORING_SQ_NEED_WAKEUP, &n.rings->sq_flags);
ctx->rings = n.rings;
+ rcu_assign_pointer(ctx->rings_rcu, n.rings);
+
ctx->sq_sqes = n.sq_sqes;
swap_old(ctx, o, n, ring_region);
swap_old(ctx, o, n, sq_region);
@@ -554,6 +562,10 @@ overflow:
out:
spin_unlock(&ctx->completion_lock);
mutex_unlock(&ctx->mmap_lock);
+
+ /* Wait for concurrent io_ctx_mark_taskrun() */
+ if (to_free == &o)
+ synchronize_rcu_expedited();
io_register_free_rings(ctx, to_free);
if (ctx->sq_data)
diff --git a/io_uring/zcrx.c b/io_uring/zcrx.c
index 93da8933a91f..262ac732cf96 100644
--- a/io_uring/zcrx.c
+++ b/io_uring/zcrx.c
@@ -898,11 +898,12 @@ static inline bool io_parse_rqe(struct io_uring_zcrx_rqe *rqe,
struct io_zcrx_ifq *ifq,
struct net_iov **ret_niov)
{
+ __u64 off = READ_ONCE(rqe->off);
unsigned niov_idx, area_idx;
struct io_zcrx_area *area;
- area_idx = rqe->off >> IORING_ZCRX_AREA_SHIFT;
- niov_idx = (rqe->off & ~IORING_ZCRX_AREA_MASK) >> ifq->niov_shift;
+ area_idx = off >> IORING_ZCRX_AREA_SHIFT;
+ niov_idx = (off & ~IORING_ZCRX_AREA_MASK) >> ifq->niov_shift;
if (unlikely(rqe->__pad || area_idx))
return false;