From 2e250fc010a2883961784261474a8fb26c10b68c Mon Sep 17 00:00:00 2001 From: Pavel Skripkin Date: Sun, 6 Feb 2022 21:05:16 +0300 Subject: [PATCH] net: asix: add proper error handling of usb read errors 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@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin Tested-by: Oleksij Rempel Reviewed-by: Greg Kroah-Hartman --- 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); -- 2.35.1