2.0 KiB
CVE-2024-50036
Description
In the Linux kernel, the following vulnerability has been resolved:net: do not delay dst_entries_add() in dst_release()dst_entries_add() uses per-cpu data that might be freed at netnsdismantle from ip6_route_net_exit() calling dst_entries_destroy()Before ip6_route_net_exit() can be called, we release allthe dsts associated with this netns, via calls to dst_release(),which waits an rcu grace period before calling dst_destroy()dst_entries_add() use in dst_destroy() is racy, becausedst_entries_destroy() could have been called already.Decrementing the number of dsts must happen sooner.Notes:1) in CONFIG_XFRM case, dst_destroy() can call dst_release_immediate(child), this might also cause UAF if the child does not have DST_NOCOUNT set. IPSEC maintainers might take a look and see how to address this.2) There is also discussion about removing this count of dst, which might happen in future kernels.
POC
Reference
No PoCs from references.