CVE-2026-64188
Description
In the Linux kernel, the following vulnerability has been resolved: net: qualcomm: rmnet: fix endpoint use-after-free in rmnet_dellink() rmnet_dellink() removes the endpoint from the hash table with hlist_del_init_rcu() and then immediately frees it with kfree(). However, RCU readers on the receive path (rmnet_rx_handler -> __rmnet_map_ingress_handler) may still hold a reference to the endpoint and dereference ep->egress_dev after the memory has been freed. The endpoint is a kmalloc-32 object, and the stale read at offset 8 corresponds to the egress_dev pointer. BUG: unable to handle page fault for address: ffffffffde942eef Oops: 0002 [#1] SMP NOPTI CPU: 1 UID: 0 PID: 137 Comm: poc_write Not tainted 7.0.0+ #4 PREEMPTLAZY RIP: 0010:rmnet_vnd_rx_fixup (rmnet_vnd.c:27) Call Trace: <TASK> __rmnet_map_ingress_handler (rmnet_handlers.c:48 rmnet_handlers.c:101) rmnet_rx_handler (rmnet_handlers.c:129 rmnet_handlers.c:235) __netif_receive_skb_core.constprop.0 (net/core/dev.c:6096) __netif_receive_skb_one_core (net/core/dev.c:6208) netif_receive_skb (net/core/dev.c:6467) tun_get_user (drivers/net/tun.c:1955) tun_chr_write_iter (drivers/net/tun.c:2003) vfs_write (fs/read_write.c:688) ksys_write (fs/read_write.c:740) </TASK> Add an rcu_head field to struct rmnet_endpoint and replace kfree() with kfree_rcu() so the endpoint memory remains valid through the RCU grace period. Also remove the rmnet_vnd_dellink() call and inline only the nr_rmnet_devs decrement, since rmnet_vnd_dellink() would set ep->egress_dev to NULL during the grace period, creating a data race with lockless readers.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
References
- https://git.kernel.org/stable/c/1078ae8175777e80c9637996fb4a46c55f0ce576
- https://git.kernel.org/stable/c/310b93246bfec7d4452507e0c15477377ed9f025
- https://git.kernel.org/stable/c/41e06fcc5df0774d212e70c5b503fc769492bce3
- https://git.kernel.org/stable/c/8b17adf6d4fb6bf61fa4c3f58366a7c082799a71
- https://git.kernel.org/stable/c/9918698cf3aee4032e12bb42fd5a951dc465339b
- https://git.kernel.org/stable/c/c4e676c3505c5058922dc1a6f1ded795f6758135
- https://git.kernel.org/stable/c/d00c953a8f69921f484b629801766da68f27f658
- https://git.kernel.org/stable/c/f193e38cb257d033060b63f1cfd94af076b3a2ab
- https://www.suse.com/security/cve/CVE-2026-64188.html
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.