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From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Pavel Begunkov <asml.silence@gmail.com>,
        Jens Axboe <axboe@kernel.dk>, Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.12 266/384] io_uring: safer sq_creds putting
Date:   Mon, 10 May 2021 12:20:55 +0200
Message-Id: <20210510102023.619191141@linuxfoundation.org>
In-Reply-To: <20210510102014.849075526@linuxfoundation.org>
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From: Pavel Begunkov <asml.silence@gmail.com>

[ Upstream commit 07db298a1c96bdba2102d60ad51fcecb961177c9 ]

Put sq_creds as a part of io_ring_ctx_free(), it's easy to miss doing it
in io_sq_thread_finish(), especially considering past mistakes related
to ring creation failures.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/3becb1866467a1de82a97345a0a90d7fb8ff875e.1618916549.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/io_uring.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index dff34975d86b..0bc4727e8a90 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -7200,8 +7200,6 @@ static void io_sq_thread_finish(struct io_ring_ctx *ctx)
 
 		io_put_sq_data(sqd);
 		ctx->sq_data = NULL;
-		if (ctx->sq_creds)
-			put_cred(ctx->sq_creds);
 	}
 }
 
@@ -8469,6 +8467,8 @@ static void io_ring_ctx_free(struct io_ring_ctx *ctx)
 	mutex_unlock(&ctx->uring_lock);
 	io_eventfd_unregister(ctx);
 	io_destroy_buffers(ctx);
+	if (ctx->sq_creds)
+		put_cred(ctx->sq_creds);
 
 #if defined(CONFIG_UNIX)
 	if (ctx->ring_sock) {
-- 
2.30.2