On 1/5/22 15:04, syzbot wrote:
Hello,
syzbot found the following issue on:
HEAD commit: b0a8b5053e8b kmsan: core: add dependency on DEBUG_KERNEL
git tree: https://github.com/google/kmsan.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=159cf693b00000
kernel config: https://syzkaller.appspot.com/x/.config?x=46a956fc7a887c60
dashboard link: https://syzkaller.appspot.com/bug?extid=6ca9f7867b77c2d316ac
compiler: clang version 14.0.0 (/usr/local/google/src/llvm-git-monorepo 2b554920f11c8b763cd9ed9003f4e19b919b8e1f), GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14413193b00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=127716a3b00000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6ca9f7867b77c2d316ac@xxxxxxxxxxxxxxxxxxxxxxxxx
asix 1-1:0.0 eth1: Failed to read reg index 0x0000: -32
asix 1-1:0.0 eth1: Failed to read reg index 0x0000: -32
=====================================================
BUG: KMSAN: uninit-value in ax88178_reset+0xfd2/0x1590 drivers/net/usb/asix_devices.c:946 drivers/net/usb/asix_devices.c:946
ax88178_reset+0xfd2/0x1590 drivers/net/usb/asix_devices.c:946 drivers/net/usb/asix_devices.c:946
usbnet_open+0x16d/0x1940 drivers/net/usb/usbnet.c:894 drivers/net/usb/usbnet.c:894
__dev_open+0x920/0xb90 net/core/dev.c:1490 net/core/dev.c:1490
__dev_change_flags+0x4da/0xd40 net/core/dev.c:8796 net/core/dev.c:8796
dev_change_flags+0xf5/0x280 net/core/dev.c:8867 net/core/dev.c:8867
devinet_ioctl+0xfc1/0x3060 net/ipv4/devinet.c:1144 net/ipv4/devinet.c:1144
inet_ioctl+0x59f/0x820 net/ipv4/af_inet.c:969 net/ipv4/af_inet.c:969
sock_do_ioctl net/socket.c:1118 [inline]
sock_do_ioctl net/socket.c:1118 [inline] net/socket.c:1235
sock_ioctl+0xa3f/0x13d0 net/socket.c:1235 net/socket.c:1235
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
vfs_ioctl fs/ioctl.c:51 [inline] fs/ioctl.c:860
__do_sys_ioctl fs/ioctl.c:874 [inline] fs/ioctl.c:860
__se_sys_ioctl+0x2df/0x4a0 fs/ioctl.c:860 fs/ioctl.c:860
__x64_sys_ioctl+0xd8/0x110 fs/ioctl.c:860 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_x64 arch/x86/entry/common.c:51 [inline] arch/x86/entry/common.c:82
do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x44/0xae
Local variable status created at:
ax88178_reset+0x69/0x1590
usbnet_open+0x16d/0x1940 drivers/net/usb/usbnet.c:894 drivers/net/usb/usbnet.c:894
Again usbnet_read_cmd() returns 0.
It seems reasonable to mark asix_read_cmd() as __must_check, so let's do
it and add missing error handling
#syz test: https://github.com/google/kmsan.git master
With regards,
Pavel Skripkin
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..df637d8284ab 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;
}
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);
