io_uring: safer sq_creds putting

[ 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>

diff --git a/fs/io_uring.c b/fs/io_uring.c
index dff34975d86bc35d023c4f69efbcbab683a5a580..0bc4727e8a9068fd4e59b85e114d54cb84dde12d 100644 (file)
--- 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) {