[PATCH 5.10 519/717] io_uring: fix ignoring xa_store errors

Greg Kroah-Hartman
2020-12-28T14:46:42Z

From: Pavel Begunkov <asml.silence@gmail.com>

commit a528b04ea40690ff40501f50d618a62a02b19620 upstream.

xa_store() may fail, check the result.

Cc: stable@vger.kernel.org # 5.10
Fixes: 0f2122045b946 ("io_uring: don't rely on weak ->files references")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/io_uring.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -8708,10 +8708,9 @@ static void io_uring_cancel_task_request
static int io_uring_add_task_file(struct io_ring_ctx *ctx, struct file *file)
{
struct io_uring_task *tctx = current->io_uring;
+ int ret;

if (unlikely(!tctx)) {
- int ret;
-
ret = io_uring_alloc_task_context(current);
if (unlikely(ret))
return ret;
@@ -8722,7 +8721,12 @@ static int io_uring_add_task_file(struct

if (!old) {
get_file(file);
- xa_store(&tctx->xa, (unsigned long)file, file, GFP_KERNEL);
+ ret = xa_err(xa_store(&tctx->xa, (unsigned long)file,
+ file, GFP_KERNEL));
+ if (ret) {
+ fput(file);
+ return ret;
+ }
}
tctx->last = file;
}