6.11-stable review patch. If anyone has any objections, please let me know.
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From: Toke Høiland-Jørgensen toke@redhat.com
[ 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@syzkaller.appspotmail.com Signed-off-by: Toke Høiland-Jørgensen toke@redhat.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Tested-by: syzbot+d121e098da06af416d23@syzkaller.appspotmail.com Reviewed-by: Alexander Lobakin aleksander.lobakin@intel.com Acked-by: Stanislav Fomichev sdf@fomichev.me Link: https://lore.kernel.org/bpf/20241030-test-run-mem-fix-v1-1-41e88e8cae43@redh... Signed-off-by: Sasha Levin sashal@kernel.org --- net/bpf/test_run.c | 1 + 1 file changed, 1 insertion(+)
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,