This is a note to let you know that I've just added the patch titled bpf, test_run: Fix LIVE_FRAME frame update after a page has been recycled to the 6.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: bpf-test_run-fix-live_frame-frame-update-after-a-pag.patch and it can be found in the queue-6.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 2d65f745d7d43c7170338fe80c8f89899aa6ba9d Author: Toke Høiland-Jørgensen <toke@xxxxxxxxxx> Date: Wed Oct 30 11:48:26 2024 +0100 bpf, test_run: Fix LIVE_FRAME frame update after a page has been recycled [ Upstream commit c40dd8c4732551605712985bc5b7045094c6458d ] The test_run code detects whether a page has been modified and re-initialises the xdp_frame structure if it has, using xdp_update_frame_from_buff(). However, xdp_update_frame_from_buff() doesn't touch frame->mem, so that wasn't correctly re-initialised, which led to the pages from page_pool not being returned correctly. Syzbot noticed this as a memory leak. Fix this by also copying the frame->mem structure when re-initialising the frame, like we do on initialisation of a new page from page_pool. Fixes: e5995bc7e2ba ("bpf, test_run: fix crashes due to XDP frame overwriting/corruption") Fixes: b530e9e1063e ("bpf: Add "live packet" mode for XDP in BPF_PROG_RUN") Reported-by: syzbot+d121e098da06af416d23@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx> Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Tested-by: syzbot+d121e098da06af416d23@xxxxxxxxxxxxxxxxxxxxxxxxx Reviewed-by: Alexander Lobakin <aleksander.lobakin@xxxxxxxxx> Acked-by: Stanislav Fomichev <sdf@xxxxxxxxxxx> Link: https://lore.kernel.org/bpf/20241030-test-run-mem-fix-v1-1-41e88e8cae43@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index 6d7a442ceb89b..501ec4249fedc 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -246,6 +246,7 @@ static void reset_ctx(struct xdp_page_head *head) head->ctx.data_meta = head->orig_ctx.data_meta; head->ctx.data_end = head->orig_ctx.data_end; xdp_update_frame_from_buff(&head->ctx, head->frame); + head->frame->mem = head->orig_ctx.rxq->mem; } static int xdp_recv_frames(struct xdp_frame **frames, int nframes,