6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
[ 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>
---
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 12a2934b28ffb..905de361f8623 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -244,6 +244,7 @@ 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,
--
2.43.0
