io_uring/kbuf: account ring io_buffer_list memory

Commit 475a8d30371604a6363da8e304a608a5959afc40 upstream.

Follow the non-ringed pbuf struct io_buffer_list allocations and account
it against the memcg. There is low chance of that being an actual
problem as ring provided buffer should either pin user memory or
allocate it, which is already accounted.

Cc: [email protected] # 6.1
Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/3985218b50d341273cafff7234e1a7e6d0db9808.1747150490.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: isilence

io_uring/kbuf.c

@@ -510,7 +510,7 @@ int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg)
 		if (bl->buf_nr_pages || !list_empty(&bl->buf_list))
 			return -EEXIST;
 	} else {
-		free_bl = bl = kzalloc(sizeof(*bl), GFP_KERNEL);
+		free_bl = bl = kzalloc(sizeof(*bl), GFP_KERNEL_ACCOUNT);
 		if (!bl)
 			return -ENOMEM;
 	}