On Wed, Jan 05, 2022 at 04:19:52PM +0300, Pavel Skripkin wrote: > Syzbot once again hit uninit value in asix driver. The problem still the > same -- asix_read_cmd() reads less bytes, than was requested by caller. > > Since all read requests are performed via asix_read_cmd() let's catch > usb related error there and add __must_check notation to be sure all > callers actually check return value. > > So, this patch adds sanity check inside asix_read_cmd(), that simply > checks if bytes read are not less, than was requested and adds missing > error handling of asix_read_cmd() all across the driver code. > > Fixes: d9fe64e51114 ("net: asix: Add in_pm parameter") > Reported-and-tested-by: syzbot+6ca9f7867b77c2d316ac@xxxxxxxxxxxxxxxxxxxxxxxxx > Signed-off-by: Pavel Skripkin <paskripkin@xxxxxxxxx> Tested-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx> Thank you! > --- > drivers/net/usb/asix.h | 4 ++-- > drivers/net/usb/asix_common.c | 19 +++++++++++++------ > drivers/net/usb/asix_devices.c | 21 ++++++++++++++++++--- > 3 files changed, 33 insertions(+), 11 deletions(-) > > diff --git a/drivers/net/usb/asix.h b/drivers/net/usb/asix.h > index 2a1e31defe71..4334aafab59a 100644 > --- a/drivers/net/usb/asix.h > +++ b/drivers/net/usb/asix.h > @@ -192,8 +192,8 @@ extern const struct driver_info ax88172a_info; > /* ASIX specific flags */ > #define FLAG_EEPROM_MAC (1UL << 0) /* init device MAC from eeprom */ > > -int asix_read_cmd(struct usbnet *dev, u8 cmd, u16 value, u16 index, > - u16 size, void *data, int in_pm); > +int __must_check asix_read_cmd(struct usbnet *dev, u8 cmd, u16 value, u16 index, > + u16 size, void *data, int in_pm); > > int asix_write_cmd(struct usbnet *dev, u8 cmd, u16 value, u16 index, > u16 size, void *data, int in_pm); > diff --git a/drivers/net/usb/asix_common.c b/drivers/net/usb/asix_common.c > index 71682970be58..524805285019 100644 > --- a/drivers/net/usb/asix_common.c > +++ b/drivers/net/usb/asix_common.c > @@ -11,8 +11,8 @@ > > #define AX_HOST_EN_RETRIES 30 > > -int asix_read_cmd(struct usbnet *dev, u8 cmd, u16 value, u16 index, > - u16 size, void *data, int in_pm) > +int __must_check asix_read_cmd(struct usbnet *dev, u8 cmd, u16 value, u16 index, > + u16 size, void *data, int in_pm) > { > int ret; > int (*fn)(struct usbnet *, u8, u8, u16, u16, void *, u16); > @@ -27,9 +27,12 @@ int asix_read_cmd(struct usbnet *dev, u8 cmd, u16 value, u16 index, > ret = fn(dev, cmd, USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE, > value, index, data, size); > > - if (unlikely(ret < 0)) > + if (unlikely(ret < size)) { > + ret = ret < 0 ? ret : -ENODATA; > + > netdev_warn(dev->net, "Failed to read reg index 0x%04x: %d\n", > index, ret); > + } > > return ret; > } > @@ -79,7 +82,7 @@ static int asix_check_host_enable(struct usbnet *dev, int in_pm) > 0, 0, 1, &smsr, in_pm); > if (ret == -ENODEV) > break; > - else if (ret < sizeof(smsr)) > + else if (ret < 0) > continue; > else if (smsr & AX_HOST_EN) > break; > @@ -579,8 +582,12 @@ int asix_mdio_read_nopm(struct net_device *netdev, int phy_id, int loc) > return ret; > } > > - asix_read_cmd(dev, AX_CMD_READ_MII_REG, phy_id, > - (__u16)loc, 2, &res, 1); > + ret = asix_read_cmd(dev, AX_CMD_READ_MII_REG, phy_id, > + (__u16)loc, 2, &res, 1); > + if (ret < 0) { > + mutex_unlock(&dev->phy_mutex); > + return ret; > + } > asix_set_hw_mii(dev, 1); > mutex_unlock(&dev->phy_mutex); > > diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c > index 4514d35ef4c4..6b2fbdf4e0fd 100644 > --- a/drivers/net/usb/asix_devices.c > +++ b/drivers/net/usb/asix_devices.c > @@ -755,7 +755,12 @@ static int ax88772_bind(struct usbnet *dev, struct usb_interface *intf) > priv->phy_addr = ret; > priv->embd_phy = ((priv->phy_addr & 0x1f) == 0x10); > > - asix_read_cmd(dev, AX_CMD_STATMNGSTS_REG, 0, 0, 1, &chipcode, 0); > + ret = asix_read_cmd(dev, AX_CMD_STATMNGSTS_REG, 0, 0, 1, &chipcode, 0); > + if (ret < 0) { > + netdev_dbg(dev->net, "Failed to read STATMNGSTS_REG: %d\n", ret); > + return ret; > + } > + > chipcode &= AX_CHIPCODE_MASK; > > ret = (chipcode == AX_AX88772_CHIPCODE) ? ax88772_hw_reset(dev, 0) : > @@ -920,11 +925,21 @@ static int ax88178_reset(struct usbnet *dev) > int gpio0 = 0; > u32 phyid; > > - asix_read_cmd(dev, AX_CMD_READ_GPIOS, 0, 0, 1, &status, 0); > + ret = asix_read_cmd(dev, AX_CMD_READ_GPIOS, 0, 0, 1, &status, 0); > + if (ret < 0) { > + netdev_dbg(dev->net, "Failed to read GPIOS: %d\n", ret); > + return ret; > + } > + > netdev_dbg(dev->net, "GPIO Status: 0x%04x\n", status); > > asix_write_cmd(dev, AX_CMD_WRITE_ENABLE, 0, 0, 0, NULL, 0); > - asix_read_cmd(dev, AX_CMD_READ_EEPROM, 0x0017, 0, 2, &eeprom, 0); > + ret = asix_read_cmd(dev, AX_CMD_READ_EEPROM, 0x0017, 0, 2, &eeprom, 0); > + if (ret < 0) { > + netdev_dbg(dev->net, "Failed to read EEPROM: %d\n", ret); > + return ret; > + } > + > asix_write_cmd(dev, AX_CMD_WRITE_DISABLE, 0, 0, 0, NULL, 0); > > netdev_dbg(dev->net, "EEPROM index 0x17 is 0x%04x\n", eeprom); > -- > 2.34.1 > > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |