diff options
| author | Sagi Grimberg <sagi@grimberg.me> | 2020-06-24 01:53:12 -0700 |
|---|---|---|
| committer | Christoph Hellwig <hch@lst.de> | 2020-06-24 18:41:20 +0200 |
| commit | c31244669f57963b6ce133a5555b118fc50aec95 (patch) | |
| tree | 0b1a46c03e62ac49e9e12b82159fca32c0cbde7f | |
| parent | d8a22f85609fadb46ba699e0136cc3ebdeebff79 (diff) | |
| download | linux-c31244669f57963b6ce133a5555b118fc50aec95.tar.gz | |
nvme-multipath: fix bogus request queue reference put
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
Reported-by: Anton Eidelman <anton@lightbitslabs.com>
Tested-by: Anton Eidelman <anton@lightbitslabs.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
| -rw-r--r-- | drivers/nvme/host/multipath.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c index 79c8caced81f89..18d084ed497ef3 100644 --- a/drivers/nvme/host/multipath.c +++ b/drivers/nvme/host/multipath.c @@ -690,6 +690,14 @@ void nvme_mpath_remove_disk(struct nvme_ns_head *head) kblockd_schedule_work(&head->requeue_work); flush_work(&head->requeue_work); blk_cleanup_queue(head->disk->queue); + 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); } |