Commit ec8516f3 authored by Dylan Yudaken's avatar Dylan Yudaken Committed by Jens Axboe
Browse files

io_uring: fix free of unallocated buffer list 



in the error path of io_register_pbuf_ring, only free bl if it was
allocated.

Reported-by: default avatarDipanjan Das <mail.dipanjan.das@gmail.com>
Fixes: c7fb1942 ("io_uring: add support for ring mapped supplied buffers")
Signed-off-by: default avatarDylan Yudaken <dylany@fb.com>
Reviewed-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/all/CANX2M5bXKw1NaHdHNVqssUUaBCs8aBpmzRNVEYEvV0n44P7ioA@mail.gmail.com/
Link: https://lore.kernel.org/all/CANX2M5YiZBXU3L6iwnaLs-HHJXRvrxM8mhPDiMDF9Y9sAvOHUA@mail.gmail.com/


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent d785a773

fs/io_uring.c

+3 −3
Original line number Original line Diff line number Diff line
@@ -12931,7 +12931,7 @@ static int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg) 
{

{

	struct io_uring_buf_ring *br;

	struct io_uring_buf_ring *br;

	struct io_uring_buf_reg reg;

	struct io_uring_buf_reg reg;

	struct io_buffer_list *bl;

	struct io_buffer_list *bl, *free_bl = NULL;

	struct page **pages;

	struct page **pages;

	int nr_pages;

	int nr_pages;
@@ -12963,7 +12963,7 @@ static int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg) 
		if (bl->buf_nr_pages || !list_empty(&bl->buf_list))

		if (bl->buf_nr_pages || !list_empty(&bl->buf_list))

			return -EEXIST;

			return -EEXIST;

	} else {

	} else {

		bl = kzalloc(sizeof(*bl), GFP_KERNEL);

		free_bl = bl = kzalloc(sizeof(*bl), GFP_KERNEL);

		if (!bl)

		if (!bl)

			return -ENOMEM;

			return -ENOMEM;

	}

	}
@@ -12972,7 +12972,7 @@ static int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg) 
			     struct_size(br, bufs, reg.ring_entries),

			     struct_size(br, bufs, reg.ring_entries),

			     &nr_pages);

			     &nr_pages);

	if (IS_ERR(pages)) {

	if (IS_ERR(pages)) {

		kfree(bl);

		kfree(free_bl);

		return PTR_ERR(pages);

		return PTR_ERR(pages);

	}

	}