From: mengfanhui <mengfanhui@kylinos.cn>
To: kbusch@kernel.org, axboe@kernel.dk, hch@lst.de
Cc: linux-kernel@vger.kernel.org, sagi@grimberg.me,
linux-nvme@lists.infradead.org, mengfanhui@kylinos.cn
Subject: [PATCH] nvme-multipath: fix bogus request queue reference put
Date: Wed, 17 Jan 2024 14:50:43 +0800 [thread overview]
Message-ID: <20240117065043.79192-1-mengfanhui@kylinos.cn> (raw)
From: Sagi Grimberg <sagi@grimberg.me>
The mpath disk node takes a reference on the request mpath
request queue when adding live path to the mpath gendisk.
However if we connected to an inaccessible path device_add_disk
is not called, so if we disconnect and remove the mpath gendisk
we endup putting an reference on the request queue that was
never taken [1].
Fix that to check if we ever added a live path (using
NVME_NS_HEAD_HAS_DISK flag) and if not, clear the disk->queue
reference.
[1]:
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 1372 at lib/refcount.c:28 refcount_warn_saturate+0xa6/0xf0
CPU: 1 PID: 1372 Comm: nvme Tainted: G O 5.7.0-rc2+ #3
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1 04/01/2014
RIP: 0010:refcount_warn_saturate+0xa6/0xf0
RSP: 0018:ffffb29e8053bdc0 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff8b7a2f4fc060 RCX: 0000000000000007
RDX: 0000000000000007 RSI: 0000000000000092 RDI: ffff8b7a3ec99980
RBP: ffff8b7a2f4fc000 R08: 00000000000002e1 R09: 0000000000000004
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: fffffffffffffff2 R14: ffffb29e8053bf08 R15: ffff8b7a320e2da0
FS: 00007f135d4ca800(0000) GS:ffff8b7a3ec80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005651178c0c30 CR3: 000000003b650005 CR4: 0000000000360ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
disk_release+0xa2/0xc0
device_release+0x28/0x80
kobject_put+0xa5/0x1b0
nvme_put_ns_head+0x26/0x70 [nvme_core]
nvme_put_ns+0x30/0x60 [nvme_core]
nvme_remove_namespaces+0x9b/0xe0 [nvme_core]
nvme_do_delete_ctrl+0x43/0x5c [nvme_core]
nvme_sysfs_delete.cold+0x8/0xd [nvme_core]
kernfs_fop_write+0xc1/0x1a0
vfs_write+0xb6/0x1a0
ksys_write+0x5f/0xe0
do_syscall_64+0x52/0x1a0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: mengfanhui <mengfanhui@kylinos.cn>
---
drivers/nvme/host/multipath.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index 2dd4137a08b2..3e579e49579c 100644
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -895,6 +895,14 @@ void nvme_mpath_remove_disk(struct nvme_ns_head *head)
/* make sure all pending bios are cleaned up */
kblockd_schedule_work(&head->requeue_work);
flush_work(&head->requeue_work);
+ if (!test_bit(NVME_NSHEAD_DISK_LIVE, &head->flags)) {
+ /*
+ * if device_add_disk wasn't called, prevent
+ * disk release to put a bogus reference on the
+ * request queue
+ */
+ head->disk->queue = NULL;
+ }
put_disk(head->disk);
}
--
2.25.1
next reply other threads:[~2024-01-17 6:52 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-01-17 6:50 mengfanhui [this message]
2024-01-17 14:04 ` [PATCH] nvme-multipath: fix bogus request queue reference put Sagi Grimberg
2024-01-17 14:39 ` Christoph Hellwig
2024-03-14 6:13 ` mengfanhui
2024-03-17 7:33 ` Sagi Grimberg
2024-03-20 2:03 ` mengfanhui
2024-03-20 9:06 ` Sagi Grimberg
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