This is a note to let you know that I've just added the patch titled
io_uring: Fix use of XArray in __io_uring_files_cancel
to the 5.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
io_uring-fix-use-of-xarray-in-__io_uring_files_cancel.patch
and it can be found in the queue-5.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Thu Oct 29 01:16:54 PM CET 2020
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Date: Fri, 9 Oct 2020 13:49:51 +0100
Subject: io_uring: Fix use of XArray in __io_uring_files_cancel
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
commit ce765372bc443573d1d339a2bf4995de385dea3a upstream.
We have to drop the lock during each iteration, so there's no advantage
to using the advanced API. Convert this to a standard xa_for_each() loop.
Reported-by: syzbot+27c12725d8ff0bfe1a13@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/io_uring.c | 19 +++++--------------
1 file changed, 5 insertions(+), 14 deletions(-)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -8008,28 +8008,19 @@ static void io_uring_attempt_task_drop(s
void __io_uring_files_cancel(struct files_struct *files)
{
struct io_uring_task *tctx = current->io_uring;
- XA_STATE(xas, &tctx->xa, 0);
+ struct file *file;
+ unsigned long index;
/* make sure overflow events are dropped */
tctx->in_idle = true;
- do {
- struct io_ring_ctx *ctx;
- struct file *file;
-
- xas_lock(&xas);
- file = xas_next_entry(&xas, ULONG_MAX);
- xas_unlock(&xas);
-
- if (!file)
- break;
-
- ctx = file->private_data;
+ xa_for_each(&tctx->xa, index, file) {
+ struct io_ring_ctx *ctx = file->private_data;
io_uring_cancel_task_requests(ctx, files);
if (files)
io_uring_del_task_file(file);
- } while (1);
+ }
}
static inline bool io_uring_task_idle(struct io_uring_task *tctx)
Patches currently in stable-queue which might be from willy@xxxxxxxxxxxxx are
queue-5.8/io_uring-convert-advanced-xarray-uses-to-the-normal-api.patch
queue-5.8/io_uring-fix-xarray-usage-in-io_uring_add_task_file.patch
queue-5.8/io_uring-fix-use-of-xarray-in-__io_uring_files_cancel.patch
