Re: [Qemu-block] [PATCH] nvme: fix oob access issue(CVE-2018-16847)

[Li Qiang]

Ping.... what't the status of this patch.

I see Kevin's new pr doesn't contain this patch.

Thanks,

Li Qiang

Li Qiang <address@hidden> 于2018年11月2日周五 上午9:22写道：

Currently, the nvme_cmb_ops mr doesn't check the addr and size.
This can lead an oob access issue. This is triggerable in the guest.
Add check to avoid this issue.

Fixes CVE-2018-16847.

Reported-by: Li Qiang <address@hidden>
Reviewed-by: Paolo Bonzini <address@hidden>
Signed-off-by: Li Qiang <address@hidden>
---
 hw/block/nvme.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/hw/block/nvme.c b/hw/block/nvme.c
index fc7dacb..d097add 100644
--- a/hw/block/nvme.c
+++ b/hw/block/nvme.c
@@ -1175,6 +1175,10 @@ static void nvme_cmb_write(void *opaque, hwaddr addr, uint64_t data,
     unsigned size)
 {
     NvmeCtrl *n = (NvmeCtrl *)opaque;
+
+    if (addr + size > NVME_CMBSZ_GETSIZE(n->bar.cmbsz)) {
+        return;
+    }
     memcpy(&n->cmbuf[addr], &data, size);
 }

@@ -1183,6 +1187,9 @@ static uint64_t nvme_cmb_read(void *opaque, hwaddr addr, unsigned size)
     uint64_t val;
     NvmeCtrl *n = (NvmeCtrl *)opaque;

+    if (addr + size > NVME_CMBSZ_GETSIZE(n->bar.cmbsz)) {
+        return 0;
+    }
     memcpy(&val, &n->cmbuf[addr], size);
     return val;
 }
--
1.8.3.1