[PATCH] atm: solos-pci: validate DMA receive size
From: Pengpeng Hou <hidden>
Date: 2026-07-05 08:45:08
Also in:
lkml
Subsystem:
atm, the rest · Maintainers:
Chas Williams, Linus Torvalds
From: Pengpeng Hou <hidden>
Date: 2026-07-05 08:45:08
Also in:
lkml
Subsystem:
atm, the rest · Maintainers:
Chas Williams, Linus Torvalds
The DMA receive path reads header->size from the RX buffer and uses it to extend the skb with skb_put(skb, size + sizeof(*header)). RX DMA skbs are allocated with RX_DMA_SIZE bytes, but the DMA path did not check that the device-provided size fits in that buffer. The MMIO path already has a similar size check against card->buffer_size. Reject an oversized DMA receive item before skb_put() and drop the invalid skb, then continue through the normal DMA RX refill path so the port is not left without a replacement receive buffer. Signed-off-by: Pengpeng Hou <redacted> ---
diff --git a/drivers/atm/solos-pci.c b/drivers/atm/solos-pci.c
--- a/drivers/atm/solos-pci.c
+++ b/drivers/atm/solos-pci.c@@ -784,6 +784,12 @@ header = (void *)skb->data; size = le16_to_cpu(header->size); + if (size > RX_DMA_SIZE - sizeof(*header)) { + dev_warn(&card->dev->dev, "Invalid DMA buffer size\n"); + dev_kfree_skb_any(skb); + goto refill_rx; + } + skb_put(skb, size + sizeof(*header)); skb_pull(skb, sizeof(*header)); } else {
@@ -865,6 +871,7 @@ break; } } +refill_rx: /* Allocate RX skbs for any ports which need them */ if (card->using_dma && card->atmdev[port] && !card->rx_skb[port]) {