The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 81b6d05ccad4f3d8a9dfb091fb46ad6978ee40e4 Mon Sep 17 00:00:00 2001
From: Pavel Begunkov <asml.silence(a)gmail.com>
Date: Mon, 4 Jan 2021 20:36:35 +0000
Subject: [PATCH] io_uring: synchronise IOPOLL on task_submit fail
io_req_task_submit() might be called for IOPOLL, do the fail path under
uring_lock to comply with IOPOLL synchronisation based solely on it.
Cc: stable(a)vger.kernel.org # 5.5+
Signed-off-by: Pavel Begunkov <asml.silence(a)gmail.com>
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
diff --git a/fs/io_uring.c b/fs/io_uring.c
index ca46f314640b..5be33fd8b6bc 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2126,15 +2126,16 @@ static void io_req_task_cancel(struct callback_head *cb)
static void __io_req_task_submit(struct io_kiocb *req)
{
struct io_ring_ctx *ctx = req->ctx;
+ bool fail;
- if (!__io_sq_thread_acquire_mm(ctx) &&
- !__io_sq_thread_acquire_files(ctx)) {
- mutex_lock(&ctx->uring_lock);
+ fail = __io_sq_thread_acquire_mm(ctx) ||
+ __io_sq_thread_acquire_files(ctx);
+ mutex_lock(&ctx->uring_lock);
+ if (!fail)
__io_queue_sqe(req, NULL);
- mutex_unlock(&ctx->uring_lock);
- } else {
+ else
__io_req_task_cancel(req, -EFAULT);
- }
+ mutex_unlock(&ctx->uring_lock);
}
static void io_req_task_submit(struct callback_head *cb)
The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From aebf5db917055b38f4945ed6d621d9f07a44ff30 Mon Sep 17 00:00:00 2001
From: Ming Lei <ming.lei(a)redhat.com>
Date: Mon, 21 Dec 2020 12:33:35 +0800
Subject: [PATCH] block: fix use-after-free in disk_part_iter_next
Make sure that bdgrab() is done on the 'block_device' instance before
referring to it for avoiding use-after-free.
Cc: <stable(a)vger.kernel.org>
Reported-by: syzbot+825f0f9657d4e528046e(a)syzkaller.appspotmail.com
Signed-off-by: Ming Lei <ming.lei(a)redhat.com>
Reviewed-by: Christoph Hellwig <hch(a)lst.de>
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
diff --git a/block/genhd.c b/block/genhd.c
index 73faec438e49..419548e92d82 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -246,15 +246,18 @@ struct block_device *disk_part_iter_next(struct disk_part_iter *piter)
part = rcu_dereference(ptbl->part[piter->idx]);
if (!part)
continue;
+ piter->part = bdgrab(part);
+ if (!piter->part)
+ continue;
if (!bdev_nr_sectors(part) &&
!(piter->flags & DISK_PITER_INCL_EMPTY) &&
!(piter->flags & DISK_PITER_INCL_EMPTY_PART0 &&
- piter->idx == 0))
+ piter->idx == 0)) {
+ bdput(piter->part);
+ piter->part = NULL;
continue;
+ }
- piter->part = bdgrab(part);
- if (!piter->part)
- continue;
piter->idx += inc;
break;
}
The patch below does not apply to the 5.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From aebf5db917055b38f4945ed6d621d9f07a44ff30 Mon Sep 17 00:00:00 2001
From: Ming Lei <ming.lei(a)redhat.com>
Date: Mon, 21 Dec 2020 12:33:35 +0800
Subject: [PATCH] block: fix use-after-free in disk_part_iter_next
Make sure that bdgrab() is done on the 'block_device' instance before
referring to it for avoiding use-after-free.
Cc: <stable(a)vger.kernel.org>
Reported-by: syzbot+825f0f9657d4e528046e(a)syzkaller.appspotmail.com
Signed-off-by: Ming Lei <ming.lei(a)redhat.com>
Reviewed-by: Christoph Hellwig <hch(a)lst.de>
Signed-off-by: Jens Axboe <axboe(a)kernel.dk>
diff --git a/block/genhd.c b/block/genhd.c
index 73faec438e49..419548e92d82 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -246,15 +246,18 @@ struct block_device *disk_part_iter_next(struct disk_part_iter *piter)
part = rcu_dereference(ptbl->part[piter->idx]);
if (!part)
continue;
+ piter->part = bdgrab(part);
+ if (!piter->part)
+ continue;
if (!bdev_nr_sectors(part) &&
!(piter->flags & DISK_PITER_INCL_EMPTY) &&
!(piter->flags & DISK_PITER_INCL_EMPTY_PART0 &&
- piter->idx == 0))
+ piter->idx == 0)) {
+ bdput(piter->part);
+ piter->part = NULL;
continue;
+ }
- piter->part = bdgrab(part);
- if (!piter->part)
- continue;
piter->idx += inc;
break;
}