Re: [PATCH net v2] ipv6: anycast: insert aca into global hash under idev->lock

From: Jiayuan Chen

Date: Sat May 30 2026 - 01:00:50 EST



On 5/30/26 4:51 AM, Jakub Kicinski wrote:
On Fri, 29 May 2026 23:22:18 +0800 Jiayuan Chen wrote:
syzbot reported a splat [1]: a slab-use-after-free in
ipv6_chk_acast_addr(), which walks the global inet6_acaddr_lst[] hash
under RCU and dereferences a struct ifacaddr6 that has already been
freed while still linked in the hash, so a later reader walks into a
dangling node.
Please do not violate the 24h repost grace period on netdev.
We are tracking the violations now, if you keep doing this
there will be consequences..


Oops, sorry about that. I slept on it and somehow got confused about the timing.

I will make sure to wait for the full 24 hours next time.