From 6e0ac3a03f3ab0d0b69d086e3226bac77a20a468 Mon Sep 17 00:00:00 2001
From: Klaus Jensen <k.jensen@samsung.com>
Date: Mon, 30 Mar 2020 23:23:15 +0200
Subject: [PATCH] hw/block/nvme: harden cmb access
Since the controller has only supported PRPs so far it has not been
required to check the ending address (addr + len - 1) of the CMB access
for validity since it has been guaranteed to be in range of the CMB.
This changes when the controller adds support for SGLs (next patch), so
add that check.
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
---
hw/block/nvme.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index 0e916d48d7..c0f1f8ccd4 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -142,7 +142,12 @@ static inline void *nvme_addr_to_cmb(NvmeCtrl *n, hwaddr addr)
static int nvme_addr_read(NvmeCtrl *n, hwaddr addr, void *buf, int size)
{
- if (n->bar.cmbsz && nvme_addr_is_cmb(n, addr)) {
+ hwaddr hi = addr + size - 1;
+ if (hi < addr) {
+ return 1;
+ }
+
+ if (n->bar.cmbsz && nvme_addr_is_cmb(n, addr) && nvme_addr_is_cmb(n, hi)) {
memcpy(buf, nvme_addr_to_cmb(n, addr), size);
return 0;
}
--
2.30.2