diff options
| author | Jens Axboe <axboe@kernel.dk> | 2025-01-22 17:03:28 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-01-22 17:10:45 -0700 |
| commit | 69a62e03f896a7382671877b6ad6aab87c53e9c3 (patch) | |
| tree | 8a030a6c624adca1c0d68c2bca9524f0fd777709 /io_uring/msg_ring.c | |
| parent | 2839ab71ac9009884fe41a7422a167a64716c0a7 (diff) | |
io_uring/msg_ring: don't leave potentially dangling ->tctx pointer
For remote posting of messages, req->tctx is assigned even though it
is never used. Rather than leave a dangling pointer, just clear it to
NULL and use the previous check for a valid submitter_task to gate on
whether or not the request should be terminated.
Reported-by: Jann Horn <jannh@google.com>
Fixes: b6f58a3f4aa8 ("io_uring: move struct io_kiocb from task_struct to io_uring_task")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring/msg_ring.c')
| -rw-r--r-- | io_uring/msg_ring.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/io_uring/msg_ring.c b/io_uring/msg_ring.c index bd3cd78d2dba..7e6f68e911f1 100644 --- a/io_uring/msg_ring.c +++ b/io_uring/msg_ring.c @@ -89,8 +89,7 @@ static void io_msg_tw_complete(struct io_kiocb *req, struct io_tw_state *ts) static int io_msg_remote_post(struct io_ring_ctx *ctx, struct io_kiocb *req, int res, u32 cflags, u64 user_data) { - req->tctx = READ_ONCE(ctx->submitter_task->io_uring); - if (!req->tctx) { + if (!READ_ONCE(ctx->submitter_task)) { kmem_cache_free(req_cachep, req); return -EOWNERDEAD; } @@ -98,6 +97,7 @@ static int io_msg_remote_post(struct io_ring_ctx *ctx, struct io_kiocb *req, io_req_set_res(req, res, cflags); percpu_ref_get(&ctx->refs); req->ctx = ctx; + req->tctx = NULL; req->io_task_work.func = io_msg_tw_complete; io_req_task_work_add_remote(req, ctx, IOU_F_TWQ_LAZY_WAKE); return 0; |