CVE-2022-50568

Summary

In the Linux kernel, the following vulnerability has been resolved:

usb: gadget: f_hid: fix f_hidg lifetime vs cdev

The embedded struct cdev does not have its lifetime correctly tied to the enclosing struct f_hidg, so there is a use-after-free if /dev/hidgN is held open while the gadget is deleted.

This can readily be replicated with libusbgx's example programs (for conciseness - operating directly via configfs is equivalent):

gadget-hid
exec 3<> /dev/hidg0
gadget-vid-pid-remove
exec 3<&-

Pull the existing device up in to struct f_hidg and make use of the cdev_device_{add,del}() helpers. This changes the lifetime of the device object to match struct f_hidg, but note that it is still added and deleted at the same time.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux71adf118946957839a13aa4d1094183e05c6c094 < 1cd7f156f6389918f760687fbbf133c86da93162affected
LinuxLinux71adf118946957839a13aa4d1094183e05c6c094 < c78c87c4e389b62f8892af7f59857447aa6d9797affected
LinuxLinux71adf118946957839a13aa4d1094183e05c6c094 < 1b6a53e447ec3d81623610c8c7ec5082b47dfdceaffected
LinuxLinux71adf118946957839a13aa4d1094183e05c6c094 < d3136b79705c2e3bba9c76adc5628af0215d798eaffected
LinuxLinux71adf118946957839a13aa4d1094183e05c6c094 < 9e4b85d815b14bd4db2deea2a54264a23de8b896affected
LinuxLinux71adf118946957839a13aa4d1094183e05c6c094 < 9e08b7f5fa00e9d550851352bd0d1ba74ccffef2affected
LinuxLinux71adf118946957839a13aa4d1094183e05c6c094 < 89ff3dfac604614287ad5aad9370c3f984ea3f4baffected
LinuxLinux2.6.35affected
LinuxLinux0 < 2.6.35unaffected
LinuxLinux4.19.270 <= 4.19.*unaffected
LinuxLinux5.4.229 <= 5.4.*unaffected
LinuxLinux5.10.163 <= 5.10.*unaffected
LinuxLinux5.15.86 <= 5.15.*unaffected
LinuxLinux6.0.16 <= 6.0.*unaffected
LinuxLinux6.1.2 <= 6.1.*unaffected
LinuxLinux6.2 <= *unaffected

Weaknesses

References