UBSAN: shift-out-of-bounds in xfrm_selector

ID	Workflow	Result	Correct	Bug	Created	Started	Finished	Revision	Error
5f5a4a6c	assessment-security	DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ✅ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌	❓	UBSAN: shift-out-of-bounds in xfrm_selector_match (3)	2026/06/15 00:02	2026/06/15 00:02	2026/06/15 01:00	4f06757f

Title	Replies (including bot)	Last reply
[PATCH 7/7] xfrm: validate selector family and prefixlen during match	1 (1)	2026/06/22 07:57
[PATCH net] xfrm: validate selector family and prefixlen during match	2 (2)	2026/06/18 07:25
[syzbot] [net?] UBSAN: shift-out-of-bounds in xfrm_selector_match (3)	0 (1)	2026/06/15 08:56

Title

Replies (including bot)

Last reply

[PATCH 7/7] xfrm: validate selector family and prefixlen during match

1 (1)

2026/06/22 07:57

[PATCH net] xfrm: validate selector family and prefixlen during match

2 (2)

2026/06/18 07:25

[syzbot] [net?] UBSAN: shift-out-of-bounds in xfrm_selector_match (3)

0 (1)

2026/06/15 08:56

Kernel	Title	Rank 🛈	Repro	Cause bisect	Count	Last	Reported	Patched	Status
linux-6.6	UBSAN: shift-out-of-bounds in xfrm_selector_match	-1			1	9d12h	9d12h	0/2	upstream: reported on 2026/07/23 23:05
upstream	UBSAN: shift-out-of-bounds in xfrm_selector_match net	-1			4	1723d	1878d	0/29	auto-closed as invalid on 2022/03/13 00:17
upstream	UBSAN: shift-out-of-bounds in xfrm_selector_match (2) net	-1	syz, C	error	10	671d	684d	28/29	fixed on 2024/11/12 23:31

Rank 🛈

linux-6.6

UBSAN: shift-out-of-bounds in xfrm_selector_match

-1

9d12h

0/2

upstream: reported on 2026/07/23 23:05

upstream

UBSAN: shift-out-of-bounds in xfrm_selector_match net

-1

1723d

1878d

0/29

auto-closed as invalid on 2022/03/13 00:17

upstream

UBSAN: shift-out-of-bounds in xfrm_selector_match (2) net

-1

syz, C

error

671d

684d

28/29

fixed on 2024/11/12 23:31

------------[ cut here ]------------ UBSAN: shift-out-of-bounds in ./include/net/xfrm.h:970:23 shift exponent -96 is negative CPU: 1 UID: 0 PID: 12115 Comm: syz.5.2221 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: <TASK> dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 ubsan_epilogue+0xa/0x30 lib/ubsan.c:233 __ubsan_handle_shift_out_of_bounds+0x36d/0x400 lib/ubsan.c:494 addr4_match include/net/xfrm.h:970 [inline] __xfrm4_selector_match net/xfrm/xfrm_policy.c:222 [inline] xfrm_selector_match+0xd5c/0x1140 net/xfrm/xfrm_policy.c:247 __xfrm_policy_check+0x5d1/0x37b0 net/xfrm/xfrm_policy.c:3715 __xfrm_policy_check2 include/net/xfrm.h:1302 [inline] xfrm_policy_check+0x475/0x880 include/net/xfrm.h:1307 vti_rcv_cb+0x3b6/0x770 net/ipv4/ip_vti.c:135 tunnel4_rcv_cb+0xd6/0x230 net/ipv4/tunnel4.c:124 xfrm_rcv_cb+0x1c7/0x310 net/xfrm/xfrm_input.c:117 xfrm_input+0x4738/0x7760 net/xfrm/xfrm_input.c:729 vti_input+0x21f/0x330 net/ipv4/ip_vti.c:69 tunnel4_rcv+0xdd/0x2d0 net/ipv4/tunnel4.c:103 ip_protocol_deliver_rcu+0x2dc/0x440 net/ipv4/ip_input.c:207 ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:241 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318 NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:6202 [inline] __netif_receive_skb net/core/dev.c:6315 [inline] netif_receive_skb_internal net/core/dev.c:6401 [inline] netif_receive_skb+0x45b/0xbf0 net/core/dev.c:6460 tun_rx_batched+0x1de/0x790 drivers/net/tun.c:1487 tun_get_user+0x2b04/0x4350 drivers/net/tun.c:1955 tun_chr_write_iter+0x113/0x200 drivers/net/tun.c:2001 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:688 ksys_write+0x150/0x270 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fca8819ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fca890f6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fca88416090 RCX: 00007fca8819ce59 RDX: 0000000000000fce RSI: 0000200000000840 RDI: 0000000000000003 RBP: 00007fca88232d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fca88416128 R14: 00007fca88416090 R15: 00007fca8853fa48 </TASK> ---[ end trace ]---

Crashes (1):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2026/06/13 21:55	upstream	2b07ea76fd28	1d2f3589	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-kasan-gce	UBSAN: shift-out-of-bounds in xfrm_selector_match

Crashes (1):

Assets (help?)