larsks

larsks

# GDB scripts for working with Linux ax.25 subsystem

define ax-devs
  set $x = ax25_dev_list
  while ($x != 0)
    printf "%s axdev:%d dev_refcnt:%d dev_untracked:%d dev_notrack:%d\n", $x->dev->name, \
      $x->refcount->refs->counter, \
      $x->dev->dev_refcnt->refs->counter, \
      $x->dev->refcnt_tracker->untracked->refs->counter, \
      $x->dev->refcnt_tracker->no_tracker->refs->counter

larsks

Apr 17 09:38:03 radio1.local kernel: ------------[ cut here ]------------
Apr 17 09:38:03 radio1.local kernel: WARNING: CPU: 0 PID: 3750 at lib/refcount.c:28 ax25_release+0x358/0x36c [ax25]
Apr 17 09:38:03 radio1.local kernel: refcount_t: underflow; use-after-free.
Apr 17 09:38:03 radio1.local kernel: Modules linked in: tun tcp_diag inet_diag mkiss overlay cmac algif_hash aes_arm_bs crypto_simd cryptd algif_skcipher af_alg bnep vc4 snd_soc_hdmi_codec drm_display_helper cec drm_dma_helper drm_kms_helper brcmfmac_wcc snd_soc_core hci_uart btbcm bluetooth brcmfmac cp210x snd_compress usbserial raspberrypi_hwmon snd_pcm_dmaengine snd_usb_audio bcm2835_codec(C) v4l2_mem2mem brcmutil snd_hwdep snd_usbmidi_lib bcm2835_v4l2(C) bcm2835_isp(C) cfg80211 bcm2835_mmal_vchiq(C) videobuf2_dma_contig videobuf2_vmalloc videobuf2_memops snd_rawmidi snd_bcm2835(C) videobuf2_v4l2 binfmt_misc snd_seq_device videodev snd_pcm snd_timer snd videobuf2_common ecdh_generic ecc rfkill mc vc_sm_cma(C) raspberrypi_gpiomem uio_pdrv_genirq 

larsks

#!/bin/bash

# Split a certificate bundle into individual certificates.
#
# This will produce files named `cert-000.crt`, `cert-001.crt`, .etc.

read -r count < <(csplit -z "$1" -f cert- -b '%03d.crt' '/^-----BEGIN CERTIFICATE-----/' '{*}' | wc -l)
echo "split $count certificates"

larsks

A couple of solutions to CS50 problem 2 ("vanity plates") along with a simple test suite.

larsks

CFLAGS = -g

example: example.o rom.o
	$(CC) -o $@ $^

rom.o: rom.S rom.bin

rom.bin:
	echo -n -e '\x09\x08\x07\x06\x05\x04\x03\x02\x01\x00' > $@

larsks

#!/bin/bash

# Create the substitute of C
git update-ref refs/heads/main $(git log -1 --pretty=%B $C | GIT_AUTHOR_NAME=$(git log -1 --pretty=%an $C) \
	GIT_AUTHOR_DATE=$(git log -1 --pretty=%ad --date=iso $C) \
	GIT_COMMITTER_NAME=$(git log -1 --pretty=%cn $C) \
	GIT_COMMITTER_DATE=$(git log -1 --pretty=%cd --date=iso $C) \
	git commit-tree -p $A -p $B -F - $C^{tree})

git update-ref refs/heads/main $(git log -1 --pretty=%B $D | GIT_AUTHOR_NAME=$(git log -1 --pretty=%an $D) \

larsks

kprobe:fib_validate_source {
    $skb = (struct sk_buff*) arg0;
    @skb[tid] = $skb;
    @ipheader[tid] = ((struct iphdr *) ($skb->head + $skb->network_header));
}

kretprobe:fib_validate_source {
    $skb = @skb[tid];
    $ipheader = @ipheader[tid];
    $version = $ipheader->version;

larsks

#!/bin/sh

SERIAL1=( -chardev stdio,id=uart1 -serial chardev:uart1 -monitor none )
SERIAL2=( -serial vc -serial vc )
SERIAL3=( -nographic -serial mon:stdio )

EMU_RASPI=( -M raspi3 )
EMU_VIRT=( -M virt -cpu cortex-a72 )

NET_TAP=(

larsks

{
  "definitions": {
    "Group": {
      "description": "A user.openshift.io/v1 Group",
      "properties": {
        "apiVersion": {
          "default": "user.openshift.io/v1",
          "title": "Apiversion",
          "type": "string"
        },