From 14cb1e7702e5cb3c58888f6aed498381a73927d2 Mon Sep 17 00:00:00 2001 From: Dmitriy Okunev Date: Mon, 14 Sep 2026 12:15:57 +0300 Subject: [PATCH] net: mvpp2: prevent buffer overflow in page_pool allocation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The per‑processor buffering scheme is supported only if the number of pools (nrxqs * 2) does not exceed MVPP2_BM_MAX_POOLS (8). This is already checked in mvpp2_probe() during the initial activation of percpu_pools. However, mvpp2_change_mtu() may later call mvpp2_bm_switch_buffers(priv, true) without this check, which can lead to an out-of-bounds access in the priv->page_pool array in mvpp2_bm_init(). The array is sized to hold MVPP2_PORT_MAX_RXQ entries, and mvpp2_get_nrxqs() may return exactly that value. The per-CPU scheme then doubles it to nrxqs * 2, exceeding the array bounds. Check that the hardware version is MVPP22 or newer and that the number of pools (nrxqs * 2) does not exceed MVPP2_BM_MAX_POOLS before switching to per-CPU mode. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 7d04b0b13b11 ("mvpp2: percpu buffers") Signed-off-by: Dmitriy Okunev Link: https://patch.msgid.link/20260914091557.71769-1-dokunevdmitriy@gmail.com Signed-off-by: Paolo Abeni --- drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c index ccc24a1301f2..848ee655c6ea 100644 --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c @@ -5086,7 +5086,8 @@ static int mvpp2_change_mtu(struct net_device *dev, int mtu) netdev_warn(dev, "mtu %d too high, switching to shared buffers", mtu); mvpp2_bm_switch_buffers(priv, false); } - } else { + } else if (priv->hw_version >= MVPP22 && + mvpp2_get_nrxqs(priv) * 2 <= MVPP2_BM_MAX_POOLS) { bool jumbo = false; int i;