linux/net
Jakub Kicinski 2ffb4f5c2c ipv6: fix NULL pointer deref in ip6_rt_get_dev_rcu()
l3mdev_master_dev_rcu() can return NULL when the slave device is being
un-slaved from a VRF. All other callers deal with this, but we lost
the fallback to loopback in ip6_rt_pcpu_alloc() -> ip6_rt_get_dev_rcu()
with commit 4832c30d54 ("net: ipv6: put host and anycast routes on
device with address").

  KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f]
  RIP: 0010:ip6_rt_pcpu_alloc (net/ipv6/route.c:1418)
  Call Trace:
   ip6_pol_route (net/ipv6/route.c:2318)
   fib6_rule_lookup (net/ipv6/fib6_rules.c:115)
   ip6_route_output_flags (net/ipv6/route.c:2607)
   vrf_process_v6_outbound (drivers/net/vrf.c:437)

I was tempted to rework the un-slaving code to clear the flag first
and insert synchronize_rcu() before we remove the upper. But looks like
the explicit fallback to loopback_dev is an established pattern.
And I guess avoiding the synchronize_rcu() is nice, too.

Fixes: 4832c30d54 ("net: ipv6: put host and anycast routes on device with address")
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20260301194548.927324-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-03 17:14:48 -08:00
..
6lowpan net: replace ND_PRINTK with dynamic debug 2025-07-10 15:27:32 -07:00
9p Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
802 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
8021q Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
appletalk Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
atm atm: lec: fix null-ptr-deref in lec_arp_clear_vccs 2026-02-28 09:33:26 -08:00
ax25 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
batman-adv Here is a batman-adv bugfix: 2026-02-26 19:15:09 -08:00
bluetooth Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
bpf Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
bridge bridge: Check relevant per-VLAN options in VLAN range grouping 2026-02-26 19:24:29 -08:00
caif Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
can Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
ceph Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
core net: Fix rcu_tasks stall in threaded busypoll 2026-03-03 13:44:28 +01:00
dcb Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
devlink Convert 'alloc_flex' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
dns_resolver net/dns_resolver: use credential guards in dns_query() 2025-11-04 12:36:51 +01:00
dsa Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
ethernet net: optimize eth_type_trans() vs CONFIG_STACKPROTECTOR_STRONG=y 2025-11-24 19:27:31 -08:00
ethtool Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
handshake treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
hsr Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
ieee802154 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
ife
ipv4 tcp: give up on stronger sk_rcvbuf checks (for now) 2026-02-28 07:55:39 -08:00
ipv6 ipv6: fix NULL pointer deref in ip6_rt_get_dev_rcu() 2026-03-03 17:14:48 -08:00
iucv Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
kcm kcm: fix zero-frag skb in frag_list on partial sendmsg error 2026-02-23 17:26:55 -08:00
key Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
l2tp Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
l3mdev net: fib_rules: Fix iif / oif matching on L3 master device 2025-04-15 17:54:56 -07:00
lapb treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
llc treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
mac80211 Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
mac802154 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
mctp Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
mpls Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
mptcp Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
ncsi Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
netfilter Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
netlabel Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
netlink Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
netrom Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
nfc Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
nsh
openvswitch Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
packet Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
phonet treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
psample treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
psp Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
qrtr Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
rds net/rds: Fix circular locking dependency in rds_tcp_tune 2026-03-03 12:57:06 +01:00
rfkill Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
rose Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
rxrpc Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
sched net/sched: Only allow act_ct to bind to clsact/ingress qdiscs and shared blocks 2026-02-27 19:06:21 -08:00
sctp Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
shaper Convert 'alloc_obj' family to use the new default GFP_KERNEL argument 2026-02-21 17:09:51 -08:00
smc Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
strparser Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-11-13 12:35:38 -08:00
sunrpc Convert more 'alloc_obj' cases to default GFP_KERNEL arguments 2026-02-21 20:03:00 -08:00
switchdev treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
tipc Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
tls Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
unix net: annotate data-races around sk->sk_{data_ready,write_space} 2026-02-26 19:23:03 -08:00
vmw_vsock Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
wireless Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
x25 treewide: Replace kmalloc with kmalloc_obj for non-scalar types 2026-02-21 01:02:28 -08:00
xdp xsk: Fix zero-copy AF_XDP fragment drop 2026-02-28 08:55:11 -08:00
xfrm Including fixes from IPsec, Bluetooth and netfilter 2026-02-26 08:00:13 -08:00
compat.c socket: Unify getsockname and getpeername implementation 2025-11-26 13:45:23 -07:00
devres.c
Kconfig net: Kconfig: discourage drop_monitor enablement 2025-10-17 16:29:26 -07:00
Kconfig.debug
Makefile psp: base PSP device support 2025-09-18 12:32:06 +02:00
socket.c net: Drop the lock in skb_may_tx_timestamp() 2026-02-24 11:27:29 +01:00
sysctl_net.c