From c87dff8cc39a2da52d98949cc1f3e9befd19cb83 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Wed, 3 Oct 2018 12:52:24 +0200 Subject: [PATCH] mt76: fix frag length allocation for usb This is correct fix for c12128ce44b0 ("mt76: use a per rx queue page fragment cache"). We use wrong length when we allocate segments for MCU transmissions, which require bigger segment size than e->buf_size. Commit 481bb0432414 ("mt76: usb: make rx page_frag_cache access atomic") partially solved the problem or actually mask it by changing mt76u_mcu_init_rx() and mt76u_alloc_queues() sequence, so e->buf_size become non zero any longer, but still not big enough to handle MCU data. Patch fixes memory corruption which can manifest itself as random, not easy to reproduce crashes, during mt76 driver load or unload. Fixes: c12128ce44b0 ("mt76: use a per rx queue page fragment cache") Signed-off-by: Stanislaw Gruszka Signed-off-by: Lorenzo Bianconi Signed-off-by: Felix Fietkau --- drivers/net/wireless/mediatek/mt76/usb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/wireless/mediatek/mt76/usb.c b/drivers/net/wireless/mediatek/mt76/usb.c index de7785c4f6af..6b643ea701e3 100644 --- a/drivers/net/wireless/mediatek/mt76/usb.c +++ b/drivers/net/wireless/mediatek/mt76/usb.c @@ -286,7 +286,7 @@ mt76u_fill_rx_sg(struct mt76_dev *dev, struct mt76u_buf *buf, void *data; int offset; - data = page_frag_alloc(&q->rx_page, q->buf_size, GFP_ATOMIC); + data = page_frag_alloc(&q->rx_page, len, GFP_ATOMIC); if (!data) break; -- 2.17.1