Commit 9865346b authored by Jens Axboe's avatar Jens Axboe
Browse files

io_uring/kbuf: check for buffer list readiness after NULL check 



Move the buffer list 'is_ready' check below the validity check for
the buffer list for a given group.

Fixes: 5cf4f52e ("io_uring: free io_buffer_list entries via RCU")
Reported-by: default avatarDan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent e53f7b54

io_uring/kbuf.c

+2 −2
Original line number Diff line number Diff line
@@ -756,6 +756,8 @@ void *io_pbuf_get_address(struct io_ring_ctx *ctx, unsigned long bgid) 


	bl = __io_buffer_get_list(ctx, smp_load_acquire(&ctx->io_bl), bgid);



	if (!bl || !bl->is_mmap)

		return NULL;

	/*

	 * Ensure the list is fully setup. Only strictly needed for RCU lookup

	 * via mmap, and in that case only for the array indexed groups. For
@@ -763,8 +765,6 @@ void *io_pbuf_get_address(struct io_ring_ctx *ctx, unsigned long bgid) 
	 */

	if (!smp_load_acquire(&bl->is_ready))

		return NULL;

	if (!bl || !bl->is_mmap)

		return NULL;



	return bl->buf_ring;

}