From: Mike Christie <mchristi@xxxxxxxxxx>
[ Upstream commit 887e975c4172d0d5670c39ead2f18ba1e4ec8133 ]
Fix bug added with the patch:
commit 8f3ea35929a0806ad1397db99a89ffee0140822a
Author: Josef Bacik <josef@xxxxxxxxxxxxxx>
Date: Mon Jul 16 12:11:35 2018 -0400
nbd: handle unexpected replies better
where if the timeout handler runs when the completion path is and we fail
to grab the mutex in the timeout handler we will leave a config reference
and cannot free the config later.
Reviewed-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
Signed-off-by: Mike Christie <mchristi@xxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/block/nbd.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 57aebc6e1c288..5d5e52c6509ce 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -355,8 +355,10 @@ static enum blk_eh_timer_return nbd_xmit_timeout(struct request *req,
}
config = nbd->config;
- if (!mutex_trylock(&cmd->lock))
+ if (!mutex_trylock(&cmd->lock)) {
+ nbd_config_put(nbd);
return BLK_EH_RESET_TIMER;
+ }
if (config->num_connections > 1) {
dev_err_ratelimited(nbd_to_dev(nbd),
--
2.20.1
