[PATCH 5.10 717/717] null_blk: Fail zone append to conventional zones

[Greg Kroah-Hartman]

From: Damien Le Moal <damien.lemoal@xxxxxxx>

commit 2e896d89510f23927ec393bee1e0570db3d5a6c6 upstream.

Conventional zones do not have a write pointer and so cannot accept zone
append writes. Make sure to fail any zone append write command issued to
a conventional zone.

Reported-by: Naohiro Aota <naohiro.aota@xxxxxxx>
Fixes: e0489ed5daeb ("null_blk: Support REQ_OP_ZONE_APPEND")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/block/null_blk_zoned.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/block/null_blk_zoned.c
+++ b/drivers/block/null_blk_zoned.c
@@ -339,8 +339,11 @@ static blk_status_t null_zone_write(stru
 
 	trace_nullb_zone_op(cmd, zno, zone->cond);
 
-	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
+	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) {
+		if (append)
+			return BLK_STS_IOERR;
 		return null_process_cmd(cmd, REQ_OP_WRITE, sector, nr_sectors);
+	}
 
 	null_lock_zone(dev, zno);