Commit 425d2393 authored by Toke Høiland-Jørgensen's avatar Toke Høiland-Jørgensen Committed by Daniel Borkmann
Browse files

bpf: Fix release of page_pool in BPF_PROG_RUN in test runner 



The live packet mode in BPF_PROG_RUN allocates a page_pool instance for
each test run instance and uses it for the packet data. On setup it creates
the page_pool, and calls xdp_reg_mem_model() to allow pages to be returned
properly from the XDP data path. However, xdp_reg_mem_model() also raises
the reference count of the page_pool itself, so the single
page_pool_destroy() count on teardown was not enough to actually release
the pool. To fix this, add an additional xdp_unreg_mem_model() call on
teardown.

Fixes: b530e9e1 ("bpf: Add "live packet" mode for XDP in BPF_PROG_RUN")
Reported-by: default avatarFreysteinn Alfredsson <freysteinn.alfredsson@kau.se>
Signed-off-by: default avatarToke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Acked-by: default avatarSong Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20220409213053.3117305-1-toke@redhat.com
parent 8de8b71b

net/bpf/test_run.c

+3 −2
Original line number Diff line number Diff line
@@ -108,6 +108,7 @@ struct xdp_test_data { 
	struct page_pool *pp;

	struct xdp_frame **frames;

	struct sk_buff **skbs;

	struct xdp_mem_info mem;

	u32 batch_size;

	u32 frame_cnt;

};
@@ -147,7 +148,6 @@ static void xdp_test_run_init_page(struct page *page, void *arg) 


static int xdp_test_run_setup(struct xdp_test_data *xdp, struct xdp_buff *orig_ctx)

{

	struct xdp_mem_info mem = {};

	struct page_pool *pp;

	int err = -ENOMEM;

	struct page_pool_params pp_params = {
@@ -174,7 +174,7 @@ static int xdp_test_run_setup(struct xdp_test_data *xdp, struct xdp_buff *orig_c 
	}



	/* will copy 'mem.id' into pp->xdp_mem_id */

	err = xdp_reg_mem_model(&mem, MEM_TYPE_PAGE_POOL, pp);

	err = xdp_reg_mem_model(&xdp->mem, MEM_TYPE_PAGE_POOL, pp);

	if (err)

		goto err_mmodel;
@@ -202,6 +202,7 @@ static int xdp_test_run_setup(struct xdp_test_data *xdp, struct xdp_buff *orig_c 


static void xdp_test_run_teardown(struct xdp_test_data *xdp)

{

	xdp_unreg_mem_model(&xdp->mem);

	page_pool_destroy(xdp->pp);

	kfree(xdp->frames);

	kfree(xdp->skbs);