eBPF USB atomic alloction error injection

bpf_usb_error_injection.txt

USB ATOMIC ALLOCATION ERROR INJECTION

Prerequisites:

- Install bcc and bcc-tools, this patch https://github.com/iovisor/bcc/pull/2044
  is needed
- The BCC tools are available at: /usr/share/bcc/tools
- Boot with the latest KOTD-debug kernel which has CONFIG_BPF_KPROBE_OVERRIDE
  enabled 

Injecting errors into an USB network device:

- lsusb output:
	Bus 004 Device 004: ID 0424:5734 Standard Microsystems Corp. 
	>>> Bus 004 Device 003: ID 0bda:8153 Realtek Semiconductor Corp. RTL8153 Gigabit Ethernet Adapter
	Bus 004 Device 002: ID 0424:5807 Standard Microsystems Corp. 
	Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
	Bus 003 Device 008: ID 0853:0100 Topre Corporation HHKB Professional
	Bus 003 Device 006: ID 0409:005a NEC Corp. HighSpeed Hub
	Bus 003 Device 004: ID 0bda:4014 Realtek Semiconductor Corp. 
	Bus 003 Device 007: ID 0424:274c Standard Microsystems Corp. 
	Bus 003 Device 005: ID 046d:c52e Logitech, Inc. MK260 Wireless Combo Receiver
	Bus 003 Device 003: ID 0424:2734 Standard Microsystems Corp. 
	Bus 003 Device 002: ID 0424:2807 Standard Microsystems Corp. 
	Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
	Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
	Bus 001 Device 002: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
	Bus 001 Device 004: ID 0c45:6713 Microdia 
	Bus 001 Device 005: ID 15aa:1555 Gearway Electronics (Dong Guan) Co., Ltd. 
	Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

- Error injection; will fail 10 times to allocate atomic memory during any
  URB sumbission by USB device [bus 4: dev 3]:
	sudo ./inject kmalloc -c 10 -P 1 -I linux/usb.h "(true)
	=> usb_submit_urb(struct urb *urb, gfp_t mem_flags)(mem_flags == GFP_ATOMIC && urb->dev->bus->busnum == 4 && urb->dev->devnum == 3)
	"

- dmesg output:
	[24734.915723] r8152 4-1.2:1.0 enp62s0u1u2: Couldn't submit rx[000000004cd74c10], ret = -12
	[24734.915727] r8152 4-1.2:1.0 enp62s0u1u2: Couldn't submit rx[000000004cd74c10], ret = -12
	[24734.915730] r8152 4-1.2:1.0 enp62s0u1u2: Couldn't submit rx[000000004cd74c10], ret = -12
	[24734.915734] r8152 4-1.2:1.0 enp62s0u1u2: Couldn't submit rx[000000004cd74c10], ret = -12
	[24734.915737] r8152 4-1.2:1.0 enp62s0u1u2: Couldn't submit rx[000000004cd74c10], ret = -12
	[24734.915741] r8152 4-1.2:1.0 enp62s0u1u2: Couldn't submit rx[000000004cd74c10], ret = -12
	[24734.915745] r8152 4-1.2:1.0 enp62s0u1u2: Couldn't submit rx[000000004cd74c10], ret = -12
	[24734.915748] r8152 4-1.2:1.0 enp62s0u1u2: Couldn't submit rx[000000004cd74c10], ret = -12
	[24734.915752] r8152 4-1.2:1.0 enp62s0u1u2: Couldn't submit rx[000000004cd74c10], ret = -12
	[24734.915756] r8152 4-1.2:1.0 enp62s0u1u2: Couldn't submit rx[000000004cd74c10], ret = -12