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

ipv6: ioam: add NULL check for idev in ipv6_hop_ioam()

Reported by Sashiko:

The function ipv6_hop_ioam() accesses
__in6_dev_get(skb->dev)->cnf.ioam6_enabled without validating the returned
idev pointer. Because addrconf_ifdown() can concurrently clear dev->ip6_ptr
via RCU, __in6_dev_get() can return NULL during interface teardown, which
could cause a NULL pointer dereference when processing an IOAM Hop-by-Hop
option.

Let's add a check and use SKB_DROP_REASON_IPV6DISABLED accordingly.

https://git.kernel.org/stable/c/09cbfd4b81ae90963dadb1de99b63b702e73290a

https://git.kernel.org/stable/c/1dca7e491f070ac49b3d934f16ee953a53b37f38

https://git.kernel.org/stable/c/902daac307eb7e1955ce05b071950f3cba88c963

https://git.kernel.org/stable/c/abdd03229414b5a52943b65a60f34b84cea5ac59

https://git.kernel.org/stable/c/c7e8971abd70e9d022f1c251ba2508f8dc7f2db8

https://git.kernel.org/stable/c/cf75eb6617042c8cff6112daeed7791809fc9dd2

https://git.kernel.org/stable/c/d4ea0dfd75011b78cebf3808f98ac4c4f51a6fb9

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