diff options
| author | Jens Axboe <axboe@kernel.dk> | 2020-01-31 22:06:52 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2020-02-04 03:27:47 +0300 |
| commit | 5d204bcfa09330972ad3428a8f81c23f371d3e6d (patch) | |
| tree | 35fdbe2c6b198f4a07fc44f09ef3c306f238e699 /fs/io_uring.c | |
| parent | 0b7b21e42ba2d6ac9595a4358a9354249605a3af (diff) | |
| download | linux-5d204bcfa09330972ad3428a8f81c23f371d3e6d.tar.xz | |
io_uring: don't map read/write iovec potentially twice
If we have a read/write that is deferred, we already setup the async IO
context for that request, and mapped it. When we later try and execute
the request and we get -EAGAIN, we don't want to attempt to re-map it.
If we do, we end up with garbage in the iovec, which typically leads
to an -EFAULT or -EINVAL completion.
Cc: stable@vger.kernel.org # 5.5
Reported-by: Dan Melnic <dmm@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'fs/io_uring.c')
| -rw-r--r-- | fs/io_uring.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/fs/io_uring.c b/fs/io_uring.c index cd07df2afe61..678a1b245e10 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2171,10 +2171,12 @@ static int io_setup_async_rw(struct io_kiocb *req, ssize_t io_size, { if (!io_op_defs[req->opcode].async_ctx) return 0; - if (!req->io && io_alloc_async_ctx(req)) - return -ENOMEM; + if (!req->io) { + if (io_alloc_async_ctx(req)) + return -ENOMEM; - io_req_map_rw(req, io_size, iovec, fast_iov, iter); + io_req_map_rw(req, io_size, iovec, fast_iov, iter); + } req->work.func = io_rw_async; return 0; } |