diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2021-07-26 14:14:31 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2021-07-26 08:58:04 -0600 |
| commit | 44eff40a32e8f5228ae041006352e32638ad2368 (patch) | |
| tree | 4cf9efc5d01517033f807345b27674e137fba238 /fs | |
| parent | 991468dcf198bb87f24da330676724a704912b47 (diff) | |
| download | linux-44eff40a32e8f5228ae041006352e32638ad2368.tar.bz2 | |
io_uring: fix io_prep_async_link locking
io_prep_async_link() may be called after arming a linked timeout,
automatically making it unsafe to traverse the linked list. Guard
with completion_lock if there was a linked timeout.
Cc: stable@vger.kernel.org # 5.9+
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/93f7c617e2b4f012a2a175b3dab6bc2f27cebc48.1627304436.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/io_uring.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index 5a0fd6bcd318..c4d2b320cdd4 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1279,8 +1279,17 @@ static void io_prep_async_link(struct io_kiocb *req) { struct io_kiocb *cur; - io_for_each_link(cur, req) - io_prep_async_work(cur); + if (req->flags & REQ_F_LINK_TIMEOUT) { + struct io_ring_ctx *ctx = req->ctx; + + spin_lock_irq(&ctx->completion_lock); + io_for_each_link(cur, req) + io_prep_async_work(cur); + spin_unlock_irq(&ctx->completion_lock); + } else { + io_for_each_link(cur, req) + io_prep_async_work(cur); + } } static void io_queue_async_work(struct io_kiocb *req) |