[syzbot] [net?] UBSAN: shift-out-of-bounds in flow_classify

[syzbot <syzbot+1dbb57d994e54aaa04d2@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    4f619d518db9 net: wwan: t7xx: Fix FSM command timeout issue
git tree:       net
console output: https://syzkaller.appspot.com/x/log.txt?x=171cb6df980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=6a2b862bf4a5409f
dashboard link: https://syzkaller.appspot.com/bug?extid=1dbb57d994e54aaa04d2
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=131abaf8580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12227818580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c7833c741299/disk-4f619d51.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d5ca349f6388/vmlinux-4f619d51.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d85b222c4799/bzImage-4f619d51.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1dbb57d994e54aaa04d2@syzkaller.appspotmail.com

------------[ cut here ]------------
UBSAN: shift-out-of-bounds in net/sched/cls_flow.c:329:23
shift exponent 9445 is too large for 32-bit type 'u32' (aka 'unsigned int')
CPU: 0 UID: 0 PID: 11 Comm: kworker/u8:0 Not tainted 6.13.0-rc3-syzkaller-00180-g4f619d518db9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:468
 flow_classify+0x24d5/0x25b0 net/sched/cls_flow.c:329
 tc_classify include/net/tc_wrapper.h:197 [inline]
 __tcf_classify net/sched/cls_api.c:1771 [inline]
 tcf_classify+0x420/0x1160 net/sched/cls_api.c:1867
 sfb_classify net/sched/sch_sfb.c:260 [inline]
 sfb_enqueue+0x3ad/0x18b0 net/sched/sch_sfb.c:318
 dev_qdisc_enqueue+0x4b/0x290 net/core/dev.c:3793
 __dev_xmit_skb net/core/dev.c:3889 [inline]
 __dev_queue_xmit+0xf0e/0x3f50 net/core/dev.c:4400
 dev_queue_xmit include/linux/netdevice.h:3168 [inline]
 neigh_hh_output include/net/neighbour.h:523 [inline]
 neigh_output include/net/neighbour.h:537 [inline]
 ip_finish_output2+0xd41/0x1390 net/ipv4/ip_output.c:236
 iptunnel_xmit+0x55d/0x9b0 net/ipv4/ip_tunnel_core.c:82
 udp_tunnel_xmit_skb+0x262/0x3b0 net/ipv4/udp_tunnel_core.c:173
 geneve_xmit_skb drivers/net/geneve.c:916 [inline]
 geneve_xmit+0x21dc/0x2d00 drivers/net/geneve.c:1039
 __netdev_start_xmit include/linux/netdevice.h:5002 [inline]
 netdev_start_xmit include/linux/netdevice.h:5011 [inline]
 xmit_one net/core/dev.c:3590 [inline]
 dev_hard_start_xmit+0x27a/0x7d0 net/core/dev.c:3606
 __dev_queue_xmit+0x1b73/0x3f50 net/core/dev.c:4434
 neigh_output include/net/neighbour.h:539 [inline]
 ip6_finish_output2+0x12c7/0x17b0 net/ipv6/ip6_output.c:141
 ip6_finish_output+0x41e/0x840 net/ipv6/ip6_output.c:226
 NF_HOOK include/linux/netfilter.h:314 [inline]
 ndisc_send_skb+0xb30/0x1450 net/ipv6/ndisc.c:511
 ndisc_send_ns+0xcc/0x160 net/ipv6/ndisc.c:669
 addrconf_dad_work+0xb45/0x16f0 net/ipv6/addrconf.c:4303
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
---[ end trace ]---


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