* [PATCH v4 1/3] net: tulip: check frame size and r/w data length
2020-03-19 9:52 [PATCH v4 0/3] net: tulip: add checks to avoid OOB access P J P
@ 2020-03-19 9:52 ` P J P
2020-03-19 9:52 ` [PATCH v4 2/3] net: tulip: add .can_recieve routine P J P
2020-03-19 9:52 ` [PATCH v4 3/3] net: tulip: flush queued packets post receive P J P
2 siblings, 0 replies; 6+ messages in thread
From: P J P @ 2020-03-19 9:52 UTC (permalink / raw)
To: Jason Wang
Cc: Prasad J Pandit, Stefan Hajnoczi, Qemu Developers, Li Qiang,
Sven Schnelle, Ziming Zhang
From: Prasad J Pandit <pjp@fedoraproject.org>
Tulip network driver while copying tx/rx buffers does not check
frame size against r/w data length. This may lead to OOB buffer
access. Add check to avoid it.
Limit iterations over descriptors to avoid potential infinite
loop issue in tulip_xmit_list_update.
Reported-by: Li Qiang <pangpei.lq@antfin.com>
Reported-by: Ziming Zhang <ezrakiez@gmail.com>
Reported-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
---
hw/net/tulip.c | 36 +++++++++++++++++++++++++++---------
1 file changed, 27 insertions(+), 9 deletions(-)
Update v3: return a value from tulip_copy_tx_buffers() and avoid infinite loop
-> https://lists.gnu.org/archive/html/qemu-devel/2020-02/msg06275.html
diff --git a/hw/net/tulip.c b/hw/net/tulip.c
index cfac2719d3..fbe40095da 100644
--- a/hw/net/tulip.c
+++ b/hw/net/tulip.c
@@ -170,6 +170,10 @@ static void tulip_copy_rx_bytes(TULIPState *s, struct tulip_descriptor *desc)
} else {
len = s->rx_frame_len;
}
+
+ if (s->rx_frame_len + len >= sizeof(s->rx_frame)) {
+ return;
+ }
pci_dma_write(&s->dev, desc->buf_addr1, s->rx_frame +
(s->rx_frame_size - s->rx_frame_len), len);
s->rx_frame_len -= len;
@@ -181,6 +185,10 @@ static void tulip_copy_rx_bytes(TULIPState *s, struct tulip_descriptor *desc)
} else {
len = s->rx_frame_len;
}
+
+ if (s->rx_frame_len + len >= sizeof(s->rx_frame)) {
+ return;
+ }
pci_dma_write(&s->dev, desc->buf_addr2, s->rx_frame +
(s->rx_frame_size - s->rx_frame_len), len);
s->rx_frame_len -= len;
@@ -227,7 +235,8 @@ static ssize_t tulip_receive(TULIPState *s, const uint8_t *buf, size_t size)
trace_tulip_receive(buf, size);
- if (size < 14 || size > 2048 || s->rx_frame_len || tulip_rx_stopped(s)) {
+ if (size < 14 || size > sizeof(s->rx_frame) - 4
+ || s->rx_frame_len || tulip_rx_stopped(s)) {
return 0;
}
@@ -275,7 +284,6 @@ static ssize_t tulip_receive_nc(NetClientState *nc,
return tulip_receive(qemu_get_nic_opaque(nc), buf, size);
}
-
static NetClientInfo net_tulip_info = {
.type = NET_CLIENT_DRIVER_NIC,
.size = sizeof(NICState),
@@ -558,7 +566,7 @@ static void tulip_tx(TULIPState *s, struct tulip_descriptor *desc)
if ((s->csr[6] >> CSR6_OM_SHIFT) & CSR6_OM_MASK) {
/* Internal or external Loopback */
tulip_receive(s, s->tx_frame, s->tx_frame_len);
- } else {
+ } else if (s->tx_frame_len <= sizeof(s->tx_frame)) {
qemu_send_packet(qemu_get_queue(s->nic),
s->tx_frame, s->tx_frame_len);
}
@@ -570,23 +578,31 @@ static void tulip_tx(TULIPState *s, struct tulip_descriptor *desc)
}
}
-static void tulip_copy_tx_buffers(TULIPState *s, struct tulip_descriptor *desc)
+static int tulip_copy_tx_buffers(TULIPState *s, struct tulip_descriptor *desc)
{
int len1 = (desc->control >> TDES1_BUF1_SIZE_SHIFT) & TDES1_BUF1_SIZE_MASK;
int len2 = (desc->control >> TDES1_BUF2_SIZE_SHIFT) & TDES1_BUF2_SIZE_MASK;
+ if (s->tx_frame_len + len1 >= sizeof(s->tx_frame)) {
+ return -1;
+ }
if (len1) {
pci_dma_read(&s->dev, desc->buf_addr1,
s->tx_frame + s->tx_frame_len, len1);
s->tx_frame_len += len1;
}
+ if (s->tx_frame_len + len2 >= sizeof(s->tx_frame)) {
+ return -1;
+ }
if (len2) {
pci_dma_read(&s->dev, desc->buf_addr2,
s->tx_frame + s->tx_frame_len, len2);
s->tx_frame_len += len2;
}
desc->status = (len1 + len2) ? 0 : 0x7fffffff;
+
+ return 0;
}
static void tulip_setup_filter_addr(TULIPState *s, uint8_t *buf, int n)
@@ -651,13 +667,15 @@ static uint32_t tulip_ts(TULIPState *s)
static void tulip_xmit_list_update(TULIPState *s)
{
+#define TULIP_DESC_MAX 128
+ uint8_t i = 0;
struct tulip_descriptor desc;
if (tulip_ts(s) != CSR5_TS_SUSPENDED) {
return;
}
- for (;;) {
+ for (i = 0; i < TULIP_DESC_MAX; i++) {
tulip_desc_read(s, s->current_tx_desc, &desc);
tulip_dump_tx_descriptor(s, &desc);
@@ -675,10 +693,10 @@ static void tulip_xmit_list_update(TULIPState *s)
s->tx_frame_len = 0;
}
- tulip_copy_tx_buffers(s, &desc);
-
- if (desc.control & TDES1_LS) {
- tulip_tx(s, &desc);
+ if (!tulip_copy_tx_buffers(s, &desc)) {
+ if (desc.control & TDES1_LS) {
+ tulip_tx(s, &desc);
+ }
}
}
tulip_desc_write(s, s->current_tx_desc, &desc);
--
2.25.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v4 2/3] net: tulip: add .can_recieve routine
2020-03-19 9:52 [PATCH v4 0/3] net: tulip: add checks to avoid OOB access P J P
2020-03-19 9:52 ` [PATCH v4 1/3] net: tulip: check frame size and r/w data length P J P
@ 2020-03-19 9:52 ` P J P
2020-03-19 10:24 ` Philippe Mathieu-Daudé
2020-03-19 9:52 ` [PATCH v4 3/3] net: tulip: flush queued packets post receive P J P
2 siblings, 1 reply; 6+ messages in thread
From: P J P @ 2020-03-19 9:52 UTC (permalink / raw)
To: Jason Wang
Cc: Prasad J Pandit, Stefan Hajnoczi, Qemu Developers, Li Qiang,
Sven Schnelle, Ziming Zhang
From: Prasad J Pandit <pjp@fedoraproject.org>
Define .can_receive routine to do sanity checks before receiving
packet data.
Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
---
hw/net/tulip.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
Update v3: define .can_receive routine
-> https://lists.gnu.org/archive/html/qemu-devel/2020-02/msg06275.html
diff --git a/hw/net/tulip.c b/hw/net/tulip.c
index fbe40095da..757f12c710 100644
--- a/hw/net/tulip.c
+++ b/hw/net/tulip.c
@@ -229,6 +229,18 @@ static bool tulip_filter_address(TULIPState *s, const uint8_t *addr)
return ret;
}
+static int
+tulip_can_receive(NetClientState *nc)
+{
+ TULIPState *s = qemu_get_nic_opaque(nc);
+
+ if (s->rx_frame_len || tulip_rx_stopped(s)) {
+ return false;
+ }
+
+ return true;
+}
+
static ssize_t tulip_receive(TULIPState *s, const uint8_t *buf, size_t size)
{
struct tulip_descriptor desc;
@@ -236,7 +248,7 @@ static ssize_t tulip_receive(TULIPState *s, const uint8_t *buf, size_t size)
trace_tulip_receive(buf, size);
if (size < 14 || size > sizeof(s->rx_frame) - 4
- || s->rx_frame_len || tulip_rx_stopped(s)) {
+ || !tulip_can_receive(s->nic->ncs)) {
return 0;
}
@@ -288,6 +300,7 @@ static NetClientInfo net_tulip_info = {
.type = NET_CLIENT_DRIVER_NIC,
.size = sizeof(NICState),
.receive = tulip_receive_nc,
+ .can_receive = tulip_can_receive,
};
static const char *tulip_reg_name(const hwaddr addr)
--
2.25.1
^ permalink raw reply related [flat|nested] 6+ messages in thread