Eyal Birger 5918c3f480 xfrm: interface: fix use-after-free after changing collect_md xfrm interface ... [ Upstream commit a90b2a1aaa ] collect_md property on xfrm interfaces can only be set on device creation, thus xfrmi_changelink() should fail when called on such interfaces. The check to enforce this was done only in the case where the xi was returned from xfrmi_locate() which doesn't look for the collect_md interface, and thus the validation was never reached. Calling changelink would thus errornously place the special interface xi in the xfrmi_net->xfrmi hash, but since it also exists in the xfrmi_net->collect_md_xfrmi pointer it would lead to a double free when the net namespace was taken down [1]. Change the check to use the xi from netdev_priv which is available earlier in the function to prevent changes in xfrm collect_md interfaces. [1] resulting oops: [ 8.516540] kernel BUG at net/core/dev.c:12029! [ 8.516552] Oops: invalid opcode: 0000 [#1] SMP NOPTI [ 8.516559] CPU: 0 UID: 0 PID: 12 Comm: kworker/u80:0 Not tainted 6.15.0-virtme #5 PREEMPT(voluntary) [ 8.516565] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 8.516569] Workqueue: netns cleanup_net [ 8.516579] RIP: 0010:unregister_netdevice_many_notify+0x101/0xab0 [ 8.516590] Code: 90 0f 0b 90 48 8b b0 78 01 00 00 48 8b 90 80 01 00 00 48 89 56 08 48 89 32 4c 89 80 78 01 00 00 48 89 b8 80 01 00 00 eb ac 90 <0f> 0b 48 8b 45 00 4c 8d a0 88 fe ff ff 48 39 c5 74 5c 41 80 bc 24 [ 8.516593] RSP: 0018:ffffa93b8006bd30 EFLAGS: 00010206 [ 8.516598] RAX: ffff98fe4226e000 RBX: ffffa93b8006bd58 RCX: ffffa93b8006bc60 [ 8.516601] RDX: 0000000000000004 RSI: 0000000000000000 RDI: dead000000000122 [ 8.516603] RBP: ffffa93b8006bdd8 R08: dead000000000100 R09: ffff98fe4133c100 [ 8.516605] R10: 0000000000000000 R11: 00000000000003d2 R12: ffffa93b8006be00 [ 8.516608] R13: ffffffff96c1a510 R14: ffffffff96c1a510 R15: ffffa93b8006be00 [ 8.516615] FS: 0000000000000000(0000) GS:ffff98fee73b7000(0000) knlGS:0000000000000000 [ 8.516619] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8.516622] CR2: 00007fcd2abd0700 CR3: 000000003aa40000 CR4: 0000000000752ef0 [ 8.516625] PKRU: 55555554 [ 8.516627] Call Trace: [ 8.516632] <TASK> [ 8.516635] ? rtnl_is_locked+0x15/0x20 [ 8.516641] ? unregister_netdevice_queue+0x29/0xf0 [ 8.516650] ops_undo_list+0x1f2/0x220 [ 8.516659] cleanup_net+0x1ad/0x2e0 [ 8.516664] process_one_work+0x160/0x380 [ 8.516673] worker_thread+0x2aa/0x3c0 [ 8.516679] ? __pfx_worker_thread+0x10/0x10 [ 8.516686] kthread+0xfb/0x200 [ 8.516690] ? __pfx_kthread+0x10/0x10 [ 8.516693] ? __pfx_kthread+0x10/0x10 [ 8.516697] ret_from_fork+0x82/0xf0 [ 8.516705] ? __pfx_kthread+0x10/0x10 [ 8.516709] ret_from_fork_asm+0x1a/0x30 [ 8.516718] </TASK> Fixes: abc340b38b ("xfrm: interface: support collect metadata mode") Reported-by: Lonial Con <kongln9170@gmail.com> Signed-off-by: Eyal Birger <eyal.birger@gmail.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sasha Levin <sashal@kernel.org>		2025-08-01 09:48:41 +01:00
..
espintcp.c	espintcp: fix skb leaks	2025-05-29 11:03:13 +02:00
Kconfig
Makefile	xfrm: support sending NAT keepalives in ESP in UDP states	2024-06-26 13:22:42 +02:00
xfrm_algo.c	net: fill in MODULE_DESCRIPTION()s for xfrm	2024-02-09 14:12:01 -08:00
xfrm_compat.c	xfrm: Add support for per cpu xfrm state handling.	2025-02-08 09:58:00 +01:00
xfrm_device.c	xfrm: Use xdo.dev instead of xdo.real_dev	2025-06-19 15:31:43 +02:00
xfrm_hash.c
xfrm_hash.h
xfrm_inout.h
xfrm_input.c	xfrm: Add an inbound percpu state cache.	2025-02-08 09:58:00 +01:00
xfrm_interface_bpf.c	bpf: treewide: Annotate BPF kfuncs in BTF	2024-01-31 20:40:56 -08:00
xfrm_interface_core.c	xfrm: interface: fix use-after-free after changing collect_md xfrm interface	2025-08-01 09:48:41 +01:00
xfrm_ipcomp.c
xfrm_nat_keepalive.c	xfrm: support sending NAT keepalives in ESP in UDP states	2024-06-26 13:22:42 +02:00
xfrm_output.c	xfrm_output: Force software GSO only in tunnel mode	2025-03-28 22:03:25 +01:00
xfrm_policy.c	xfrm: Sanitize marks before insert	2025-05-29 11:03:15 +02:00
xfrm_proc.c	xfrm: Add dir validation to "in" data path lookup	2024-05-01 10:06:27 +02:00
xfrm_replay.c	xfrm: replay: Fix the update of replay_esn->oseq_hi for GSO	2025-02-08 09:58:00 +01:00
xfrm_state_bpf.c	bpf: treewide: Annotate BPF kfuncs in BTF	2024-01-31 20:40:56 -08:00
xfrm_state.c	xfrm: state: use a consistent pcpu_id in xfrm_state_find	2025-08-01 09:48:40 +01:00
xfrm_sysctl.c	net: Remove ctl_table sentinel elements from several networking subsystems	2024-05-03 13:29:42 +01:00
xfrm_user.c	xfrm: validate assignment of maximal possible SEQ number	2025-06-27 11:11:31 +01:00