[PATCH 6.19 815/844] io_uring/zcrx: check unsupported flags on import

[Sasha Levin]

From: Pavel Begunkov <asml.silence@xxxxxxxxx>

[ Upstream commit 7496e658a76a61758b20e27cea8abcfeafe3aec4 ]

The imoorted zcrx registration path checks for ZCRX_REG_IMPORT, as it
should, but doesn't reject any unsupported flags. Fix that.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 00d91481279fb ("io_uring/zcrx: share an ifq between rings")
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 io_uring/zcrx.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/io_uring/zcrx.c b/io_uring/zcrx.c
index 84e37900c0682..d41aa01a26d31 100644
--- a/io_uring/zcrx.c
+++ b/io_uring/zcrx.c
@@ -677,6 +677,8 @@ static int import_zcrx(struct io_ring_ctx *ctx,
 		return -EINVAL;
 	if (reg->if_rxq || reg->rq_entries || reg->area_ptr || reg->region_ptr)
 		return -EINVAL;
+	if (reg->flags & ~ZCRX_REG_IMPORT)
+		return -EINVAL;
 
 	fd = reg->if_idx;
 	CLASS(fd, f)(fd);
-- 
2.51.0