In the Linux kernel, the following vulnerability has been resolved:
ax25: properly unshare skbs in ax25_kiss_rcv()
Bernard Pidoux reported a regression apparently caused by commit c353e8983e0d ("net: introduce per netns packet chains").
skb->dev becomes NULL and we crash in __netif_receive_skb_core().
Before above commit, different kind of bugs or corruptions could happen without a major crash.
But the root cause is that ax25_kiss_rcv() can queue/mangle input skb without checking if this skb is shared or not.
Many thanks to Bernard Pidoux for his help, diagnosis and tests.
We had a similar issue years ago fixed with commit 7aaed57c5c28 ("phonet: properly unshare skbs in phonet_rcv()").
| Software | From | Fixed in |
|---|---|---|
| linux / linux_kernel | 2.6.12.1 | 5.4.299 |
| linux / linux_kernel | 5.5 | 5.10.243 |
| linux / linux_kernel | 5.11 | 5.15.192 |
| linux / linux_kernel | 5.16 | 6.1.151 |
| linux / linux_kernel | 6.2 | 6.6.105 |
| linux / linux_kernel | 6.7 | 6.12.46 |
| linux / linux_kernel | 6.13 | 6.16.6 |
| linux / linux_kernel | 2.6.12 | 2.6.12.x |
| linux / linux_kernel | 2.6.12-rc2 | 2.6.12-rc2.x |
| linux / linux_kernel | 2.6.12-rc3 | 2.6.12-rc3.x |
| linux / linux_kernel | 2.6.12-rc4 | 2.6.12-rc4.x |
| linux / linux_kernel | 2.6.12-rc5 | 2.6.12-rc5.x |
| linux / linux_kernel | 6.17-rc1 | 6.17-rc1.x |
| linux / linux_kernel | 6.17-rc2 | 6.17-rc2.x |
| linux / linux_kernel | 6.17-rc3 | 6.17-rc3.x |
| linux / linux_kernel | 6.17-rc4 | 6.17-rc4.x |
| debian / debian_linux | 11.0 | 11.0.x |