diff options
| author | Jan Kara <jack@suse.cz> | 2019-06-19 09:05:41 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-07-10 09:56:31 +0200 |
| commit | 93709767272bf10f0244e2ca4d174c20668f5a54 (patch) | |
| tree | 97cca2a8f40b84eac1a70eb61148cce586e65c34 | |
| parent | bd6042e9c3733f6fffc98ee88e239844d6f53a5d (diff) | |
scsi: vmw_pscsi: Fix use-after-free in pvscsi_queue_lck()
commit 240b4cc8fd5db138b675297d4226ec46594d9b3b upstream.
Once we unlock adapter->hw_lock in pvscsi_queue_lck() nothing prevents just
queued scsi_cmnd from completing and freeing the request. Thus cmd->cmnd[0]
dereference can dereference already freed request leading to kernel crashes
or other issues (which one of our customers observed). Store cmd->cmnd[0]
in a local variable before unlocking adapter->hw_lock to fix the issue.
CC: <stable@vger.kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/scsi/vmw_pvscsi.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/scsi/vmw_pvscsi.c b/drivers/scsi/vmw_pvscsi.c index 23081ed8f1e3..3f2a5d6c437b 100644 --- a/drivers/scsi/vmw_pvscsi.c +++ b/drivers/scsi/vmw_pvscsi.c @@ -733,6 +733,7 @@ static int pvscsi_queue_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd struct pvscsi_adapter *adapter = shost_priv(host); struct pvscsi_ctx *ctx; unsigned long flags; + unsigned char op; spin_lock_irqsave(&adapter->hw_lock, flags); @@ -745,13 +746,14 @@ static int pvscsi_queue_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd } cmd->scsi_done = done; + op = cmd->cmnd[0]; dev_dbg(&cmd->device->sdev_gendev, - "queued cmd %p, ctx %p, op=%x\n", cmd, ctx, cmd->cmnd[0]); + "queued cmd %p, ctx %p, op=%x\n", cmd, ctx, op); spin_unlock_irqrestore(&adapter->hw_lock, flags); - pvscsi_kick_io(adapter, cmd->cmnd[0]); + pvscsi_kick_io(adapter, op); return 0; } |