From 3a11d8ae00c9e4cda68f331fafd3a79549fea626 Mon Sep 17 00:00:00 2001 From: Alexey Kodanev Date: Wed, 26 Nov 2025 10:43:27 +0000 Subject: [PATCH] net: stmmac: fix rx limit check in stmmac_rx_zc() [ Upstream commit 8048168df56e225c94e50b04cb7b0514135d7a1c ] The extra "count >= limit" check in stmmac_rx_zc() is redundant and has no effect because the value of "count" doesn't change after the while condition at this point. However, it can change after "read_again:" label: while (count < limit) { ... if (count >= limit) break; read_again: ... /* XSK pool expects RX frame 1:1 mapped to XSK buffer */ if (likely(status & rx_not_ls)) { xsk_buff_free(buf->xdp); buf->xdp = NULL; dirty++; count++; goto read_again; } ... This patch addresses the same issue previously resolved in stmmac_rx() by commit fa02de9e7588 ("net: stmmac: fix rx budget limit check"). The fix is the same: move the check after the label to ensure that it bounds the goto loop. Fixes: bba2556efad6 ("net: stmmac: Enable RX via AF_XDP zero-copy") Signed-off-by: Alexey Kodanev Reviewed-by: Russell King (Oracle) Link: https://patch.msgid.link/20251126104327.175590-1-aleksei.kodanev@bell-sw.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index 7b90ecd3a55e6..86e912471dead 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -5258,10 +5258,10 @@ static int stmmac_rx_zc(struct stmmac_priv *priv, int limit, u32 queue) len = 0; } +read_again: if (count >= limit) break; -read_again: buf1_len = 0; entry = next_entry; buf = &rx_q->buf_pool[entry]; -- 2.47.3