In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: Avoid creating sub-groups asynchronously The asynchronous creation of sub-groups by a delayed work could lead to a NULL pointer dereference when the driver directory is removed before the work completes. The crash can be easily reproduced with the following commands: # cd /sys/kernel/config/pciep/functions/pciepftest # for i in {1..20}; do mkdir test && rmdir test; done BUG: kernel NULL pointer dereference, address: 0000000000000088 ... Call Trace: configfsregistergroup+0x3d/0x190 pciepfcfswork+0x41/0x110 processonework+0x18f/0x350 workerthread+0x25a/0x3a0 Fix this issue by using configfsadddefaultgroup() API which does not have the deadlock problem as configfsregistergroup() and does not require the delayed work handler. [mani: slightly reworded the description and added stable list]