On 21-08-01 22:35:13, Pavel Skripkin wrote:
> On Sun, 1 Aug 2021 15:36:27 +0300
> Petko Manolov <petkan@xxxxxxxxxxxxx> wrote:
>
> > On 21-07-31 00:44:11, Pavel Skripkin wrote:
> > > Syzbot reported uninit value pegasus_probe(). The problem was in missing
> > > error handling.
> > >
> > > get_interrupt_interval() internally calls read_eprom_word() which can fail
> > > in some cases. For example: failed to receive usb control message. These
> > > cases should be handled to prevent uninit value bug, since
> > > read_eprom_word() will not initialize passed stack variable in case of
> > > internal failure.
> >
> > Well, this is most definitelly a bug.
> >
> > ACK!
> >
> >
> > Petko
> >
> >
>
> Thank you, Petko!
>
>
> BTW: I found a lot uses of {get,set}_registers without error checking. I
> think, some of them could be fixed easily (like in enable_eprom_write), but, I
> guess, disable_eprom_write is not so easy. For example, if we cannot disable
> eprom should we retry? If not, will device get in some unexpected state?
>
> Im not familiar with this device, but I can prepare a patch to wrap all these
> calls with proper error checking
Here goes a preliminary patch that should apply on top of your, maybe with just
a few warnings. This is a review only diff, not the real patch. It's against
5.14-rc4.
I am mildly curious why syzbot didn't catch the same type of bug in
enable_net_traffic() and setup_pegasus_II() for example.
Petko
---
diff --git a/drivers/net/usb/pegasus.c b/drivers/net/usb/pegasus.c
index 9a907182569c..eafbe8107907 100644
--- a/drivers/net/usb/pegasus.c
+++ b/drivers/net/usb/pegasus.c
@@ -26,6 +26,8 @@
* ...
* v0.9.3 simplified [get|set]_register(s), async update registers
* logic revisited, receive skb_pool removed.
+ * v1.0.1 add error checking for set_register(s)(), see if calling
+ * get_registers() has failed and print a message accordingly.
*/
#include <linux/sched.h>
@@ -45,7 +47,7 @@
/*
* Version Information
*/
-#define DRIVER_VERSION "v0.9.3 (2013/04/25)"
+#define DRIVER_VERSION "v1.0.1 (2021/08/01)"
#define DRIVER_AUTHOR "Petko Manolov <petkan@xxxxxxxxxxxxx>"
#define DRIVER_DESC "Pegasus/Pegasus II USB Ethernet driver"
@@ -132,9 +134,15 @@ static int get_registers(pegasus_t *pegasus, __u16 indx, __u16 size, void *data)
static int set_registers(pegasus_t *pegasus, __u16 indx, __u16 size,
const void *data)
{
- return usb_control_msg_send(pegasus->usb, 0, PEGASUS_REQ_SET_REGS,
+ int ret;
+
+ ret = usb_control_msg_send(pegasus->usb, 0, PEGASUS_REQ_SET_REGS,
PEGASUS_REQT_WRITE, 0, indx, data, size,
1000, GFP_NOIO);
+ if (ret < 0)
+ netif_dbg(pegasus, drv, pegasus->net, "%s failed with %d\n", __func__, ret);
+
+ return ret;
}
/*
@@ -145,10 +153,15 @@ static int set_registers(pegasus_t *pegasus, __u16 indx, __u16 size,
static int set_register(pegasus_t *pegasus, __u16 indx, __u8 data)
{
void *buf = &data;
+ int ret;
- return usb_control_msg_send(pegasus->usb, 0, PEGASUS_REQ_SET_REG,
+ ret = usb_control_msg_send(pegasus->usb, 0, PEGASUS_REQ_SET_REG,
PEGASUS_REQT_WRITE, data, indx, buf, 1,
1000, GFP_NOIO);
+ if (ret < 0)
+ netif_dbg(pegasus, drv, pegasus->net, "%s failed with %d\n", __func__, ret);
+
+ return ret;
}
static int update_eth_regs_async(pegasus_t *pegasus)
@@ -188,10 +201,9 @@ static int update_eth_regs_async(pegasus_t *pegasus)
static int __mii_op(pegasus_t *p, __u8 phy, __u8 indx, __u16 *regd, __u8 cmd)
{
- int i;
- __u8 data[4] = { phy, 0, 0, indx };
+ int i, ret = -ETIMEDOUT;
__le16 regdi;
- int ret = -ETIMEDOUT;
+ __u8 data[4] = { phy, 0, 0, indx };
if (cmd & PHY_WRITE) {
__le16 *t = (__le16 *) & data[1];
@@ -211,8 +223,9 @@ static int __mii_op(pegasus_t *p, __u8 phy, __u8 indx, __u16 *regd, __u8 cmd)
goto fail;
if (cmd & PHY_READ) {
ret = get_registers(p, PhyData, 2, ®di);
+ if (ret < 0)
+ goto fail;
*regd = le16_to_cpu(regdi);
- return ret;
}
return 0;
fail:
@@ -235,9 +248,13 @@ static int write_mii_word(pegasus_t *pegasus, __u8 phy, __u8 indx, __u16 *regd)
static int mdio_read(struct net_device *dev, int phy_id, int loc)
{
pegasus_t *pegasus = netdev_priv(dev);
+ int ret;
u16 res;
- read_mii_word(pegasus, phy_id, loc, &res);
+ ret = read_mii_word(pegasus, phy_id, loc, &res);
+ if (ret < 0)
+ return ret;
+
return (int)res;
}
@@ -251,10 +268,9 @@ static void mdio_write(struct net_device *dev, int phy_id, int loc, int val)
static int read_eprom_word(pegasus_t *pegasus, __u8 index, __u16 *retdata)
{
- int i;
- __u8 tmp = 0;
+ int ret, i;
__le16 retdatai;
- int ret;
+ __u8 tmp = 0;
set_register(pegasus, EpromCtrl, 0);
set_register(pegasus, EpromOffset, index);
@@ -262,21 +278,25 @@ static int read_eprom_word(pegasus_t *pegasus, __u8 index, __u16 *retdata)
for (i = 0; i < REG_TIMEOUT; i++) {
ret = get_registers(pegasus, EpromCtrl, 1, &tmp);
+ if (ret < 0)
+ goto fail;
if (tmp & EPROM_DONE)
break;
- if (ret == -ESHUTDOWN)
- goto fail;
}
- if (i >= REG_TIMEOUT)
+ if (i >= REG_TIMEOUT) {
+ ret = -ETIMEDOUT;
goto fail;
+ }
ret = get_registers(pegasus, EpromData, 2, &retdatai);
+ if (ret < 0)
+ goto fail;
*retdata = le16_to_cpu(retdatai);
return ret;
fail:
- netif_warn(pegasus, drv, pegasus->net, "%s failed\n", __func__);
- return -ETIMEDOUT;
+ netif_dbg(pegasus, drv, pegasus->net, "%s failed\n", __func__);
+ return ret;
}
#ifdef PEGASUS_WRITE_EEPROM
@@ -324,10 +344,10 @@ static int write_eprom_word(pegasus_t *pegasus, __u8 index, __u16 data)
return ret;
fail:
- netif_warn(pegasus, drv, pegasus->net, "%s failed\n", __func__);
+ netif_dbg(pegasus, drv, pegasus->net, "%s failed\n", __func__);
return -ETIMEDOUT;
}
-#endif /* PEGASUS_WRITE_EEPROM */
+#endif /* PEGASUS_WRITE_EEPROM */
static inline int get_node_id(pegasus_t *pegasus, u8 *id)
{
@@ -367,19 +387,21 @@ static void set_ethernet_addr(pegasus_t *pegasus)
return;
err:
eth_hw_addr_random(pegasus->net);
- dev_info(&pegasus->intf->dev, "software assigned MAC address.\n");
+ netif_dbg(pegasus, drv, pegasus->net, "software assigned MAC address.\n");
return;
}
static inline int reset_mac(pegasus_t *pegasus)
{
+ int ret, i;
__u8 data = 0x8;
- int i;
set_register(pegasus, EthCtrl1, data);
for (i = 0; i < REG_TIMEOUT; i++) {
- get_registers(pegasus, EthCtrl1, 1, &data);
+ ret = get_registers(pegasus, EthCtrl1, 1, &data);
+ if (ret < 0)
+ goto fail;
if (~data & 0x08) {
if (loopback)
break;
@@ -402,22 +424,29 @@ static inline int reset_mac(pegasus_t *pegasus)
}
if (usb_dev_id[pegasus->dev_index].vendor == VENDOR_ELCON) {
__u16 auxmode;
- read_mii_word(pegasus, 3, 0x1b, &auxmode);
+ ret = read_mii_word(pegasus, 3, 0x1b, &auxmode);
+ if (ret < 0)
+ goto fail;
auxmode |= 4;
write_mii_word(pegasus, 3, 0x1b, &auxmode);
}
return 0;
+fail:
+ netif_dbg(pegasus, drv, pegasus->net, "%s failed\n", __func__);
+ return ret;
}
static int enable_net_traffic(struct net_device *dev, struct usb_device *usb)
{
- __u16 linkpart;
- __u8 data[4];
pegasus_t *pegasus = netdev_priv(dev);
int ret;
+ __u16 linkpart;
+ __u8 data[4];
- read_mii_word(pegasus, pegasus->phy, MII_LPA, &linkpart);
+ ret = read_mii_word(pegasus, pegasus->phy, MII_LPA, &linkpart);
+ if (ret < 0)
+ goto fail;
data[0] = 0xc8; /* TX & RX enable, append status, no CRC */
data[1] = 0;
if (linkpart & (ADVERTISE_100FULL | ADVERTISE_10FULL))
@@ -435,11 +464,16 @@ static int enable_net_traffic(struct net_device *dev, struct usb_device *usb)
usb_dev_id[pegasus->dev_index].vendor == VENDOR_LINKSYS2 ||
usb_dev_id[pegasus->dev_index].vendor == VENDOR_DLINK) {
u16 auxmode;
- read_mii_word(pegasus, 0, 0x1b, &auxmode);
+ ret = read_mii_word(pegasus, 0, 0x1b, &auxmode);
+ if (ret < 0)
+ goto fail;
auxmode |= 4;
write_mii_word(pegasus, 0, 0x1b, &auxmode);
}
+ return 0;
+fail:
+ netif_dbg(pegasus, drv, pegasus->net, "%s failed\n", __func__);
return ret;
}
@@ -447,9 +481,9 @@ static void read_bulk_callback(struct urb *urb)
{
pegasus_t *pegasus = urb->context;
struct net_device *net;
+ u8 *buf = urb->transfer_buffer;
int rx_status, count = urb->actual_length;
int status = urb->status;
- u8 *buf = urb->transfer_buffer;
__u16 pkt_len;
if (!pegasus)
@@ -1049,6 +1083,7 @@ static __u8 mii_phy_probe(pegasus_t *pegasus)
static inline void setup_pegasus_II(pegasus_t *pegasus)
{
+ int ret;
__u8 data = 0xa5;
set_register(pegasus, Reg1d, 0);
@@ -1060,7 +1095,9 @@ static inline void setup_pegasus_II(pegasus_t *pegasus)
set_register(pegasus, Reg7b, 2);
set_register(pegasus, 0x83, data);
- get_registers(pegasus, 0x83, 1, &data);
+ ret = get_registers(pegasus, 0x83, 1, &data);
+ if (ret < 0)
+ goto fail;
if (data == 0xa5)
pegasus->chip = 0x8513;
@@ -1075,6 +1112,8 @@ static inline void setup_pegasus_II(pegasus_t *pegasus)
set_register(pegasus, Reg81, 6);
else
set_register(pegasus, Reg81, 2);
+fail:
+ netif_dbg(pegasus, drv, pegasus->net, "%s failed\n", __func__);
}
static void check_carrier(struct work_struct *work)
