On an error path in NVM_DEV_CREATE ioctl blk_put_queue is being called
twice: one via blk_cleanup_queue and another via put_disk. Straight fix
seems to remove queue pointer so that disk_release never ends up caling
blk_put_queue again.
[ 391.808827] WARNING: CPU: 1 PID: 1250 at lib/refcount.c:128 refcount_sub_and_test+0x70/0x80
[ 391.808830] refcount_t: underflow; use-after-free.
[ 391.808832] Modules linked in: nf_conntrack_netbios_ns............
[ 391.809052] CPU: 1 PID: 1250 Comm: nvme Not tainted.........
[ 391.809057] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[ 391.809060] Call Trace:
[ 391.809079] dump_stack+0x63/0x86
[ 391.809094] __warn+0xcb/0xf0
[ 391.809103] warn_slowpath_fmt+0x5f/0x80
[ 391.809118] refcount_sub_and_test+0x70/0x80
[ 391.809125] refcount_dec_and_test+0x11/0x20
[ 391.809136] kobject_put+0x1f/0x60
[ 391.809149] blk_put_queue+0x15/0x20
[ 391.809159] disk_release+0xae/0xf0
[ 391.809172] device_release+0x32/0x90
[ 391.809184] kobject_release+0x6a/0x170
[ 391.809196] kobject_put+0x2f/0x60
[ 391.809206] put_disk+0x17/0x20
[ 391.809219] nvm_ioctl_dev_create.isra.16+0x897/0xa30
[ 391.809236] nvm_ctl_ioctl+0x23c/0x4c0
[ 391.809248] do_vfs_ioctl+0xa3/0x5f0
[ 391.809258] SyS_ioctl+0x79/0x90
[ 391.809271] entry_SYSCALL_64_fastpath+0x1a/0xa9
[ 391.809280] RIP: 0033:0x7f5d3ef363c7
[ 391.809286] RSP: 002b:00007ffc72ed8d78 EFLAGS: 00000206 ORIG_RAX: 0000000000000010
[ 391.809296] RAX: ffffffffffffffda RBX: 00007ffc72edb552 RCX: 00007f5d3ef363c7
[ 391.809301] RDX: 00007ffc72ed8d90 RSI: 0000000040804c22 RDI: 0000000000000003
[ 391.809306] RBP: 0000000000000001 R08: 0000000000000020 R09: 0000000000000001
[ 391.809311] R10: 000000000000053f R11: 0000000000000206 R12: 0000000000000000
[ 391.809316] R13: 0000000000000000 R14: 00007ffc72edb58d R15: 00007ffc72edb581
Signed-off-by: Rakesh Pandit <rakesh@xxxxxxxxxx>
---
drivers/lightnvm/core.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index 2c26af3..5d7aa45 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -309,6 +309,7 @@ static int nvm_create_tgt(struct nvm_dev *dev, struct nvm_ioctl_create *create)
tt->exit(targetdata);
err_init:
blk_cleanup_queue(tqueue);
+ tdisk->queue = NULL;
err_disk:
put_disk(tdisk);
err_dev:
--
2.5.5
