cbcvebase.
CVE-2025-40189
published 2025-11-12

CVE-2025-40189: In the Linux kernel, the following vulnerability has been resolved: net: usb: lan78xx: Fix lost EEPROM read timeout error(-ETIMEDOUT) in…

PriorityP422
EPSS
0.18%
7.8th percentile
In the Linux kernel, the following vulnerability has been resolved: net: usb: lan78xx: Fix lost EEPROM read timeout error(-ETIMEDOUT) in lan78xx_read_raw_eeprom Syzbot reported read of uninitialized variable BUG with following call stack. lan78xx 8-1:1.0 (unnamed net_device) (uninitialized): EEPROM read operation timeout BUG: KMSAN: uninit-value in lan78xx_read_eeprom drivers/net/usb/lan78xx.c:1095 [inline] BUG: KMSAN: uninit-value in lan78xx_init_mac_address drivers/net/usb/lan78xx.c:1937 [inline] BUG: KMSAN: uninit-value in lan78xx_reset+0x999/0x2cd0 drivers/net/usb/lan78xx.c:3241 lan78xx_read_eeprom drivers/net/usb/lan78xx.c:1095 [inline] lan78xx_init_mac_address drivers/net/usb/lan78xx.c:1937 [inline] lan78xx_reset+0x999/0x2cd0 drivers/net/usb/lan78xx.c:3241 lan78xx_bind+0x711/0x1690 drivers/net/usb/lan78xx.c:3766 lan78xx_probe+0x225c/0x3310 drivers/net/usb/lan78xx.c:4707 Local variable sig.i.i created at: lan78xx_read_eeprom drivers/net/usb/lan78xx.c:1092 [inline] lan78xx_init_mac_address drivers/net/usb/lan78xx.c:1937 [inline] lan78xx_reset+0x77e/0x2cd0 drivers/net/usb/lan78xx.c:3241 lan78xx_bind+0x711/0x1690 drivers/net/usb/lan78xx.c:3766 The function lan78xx_read_raw_eeprom failed to properly propagate EEPROM read timeout errors (-ETIMEDOUT). In the fallthrough path, it first attempted to restore the pin configuration for LED outputs and then returned only the status of that restore operation, discarding the original timeout error. As a result, callers could mistakenly treat the data buffer as valid even though the EEPROM read had actually timed out with no data or partial data. To fix this, handle errors in restoring the LED pin configuration separately. If the restore succeeds, return any prior EEPROM timeout error correctly to the caller.

Affected

9 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.17.6-1 (forky)linux 6.17.6-1 (forky)
linuxlinux
linuxlinux>= 8b1b2ca83b200fa46fdfb81e80ad5fe34537e6d4 < a72a7c4f675080a324d4c2167bd2314d968279f1a72a7c4f675080a324d4c2167bd2314d968279f1
linuxlinux>= 8b1b2ca83b200fa46fdfb81e80ad5fe34537e6d4 < 49bdb63ff64469a6de8ea901aef123c75be9bbe749bdb63ff64469a6de8ea901aef123c75be9bbe7
linuxlinux_kernel>= 0 < 6.17.6-16.17.6-1
linuxlinux_kernel>= 0 < 6.17.0-14.146.17.0-14.14
linuxlinux_kernel>= 6.14.0 < 6.17.46.17.4
ubuntulinux-aws
ubuntulinux-oracle
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