==================================================================
BUG: KASAN: slab-use-after-free in dev_hard_header include/linux/netdevice.h:3436 [inline]
BUG: KASAN: slab-use-after-free in ipvlan_hard_header+0xa2/0x120 drivers/net/ipvlan/ipvlan_main.c:385
Read of size 8 at addr ffff888056ad6010 by task dhcpcd-run-hook/10782
CPU: 0 UID: 0 PID: 10782 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
<IRQ>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xba/0x230 mm/kasan/report.c:482
kasan_report+0x117/0x150 mm/kasan/report.c:595
dev_hard_header include/linux/netdevice.h:3436 [inline]
ipvlan_hard_header+0xa2/0x120 drivers/net/ipvlan/ipvlan_main.c:385
dev_hard_header include/linux/netdevice.h:3439 [inline]
tipc_l2_send_msg+0x31f/0x400 net/tipc/bearer.c:514
tipc_bearer_xmit_skb+0x2b3/0x400 net/tipc/bearer.c:575
tipc_disc_timeout+0x595/0x6f0 net/tipc/discover.c:338
call_timer_fn+0x192/0x640 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2373 [inline]
__run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385
run_timer_base kernel/time/timer.c:2394 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404
handle_softirqs+0x22a/0x870 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
invoke_softirq kernel/softirq.c:496 [inline]
__irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723
irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:csd_lock_wait kernel/smp.c:342 [inline]
RIP: 0010:smp_call_function_many_cond+0xce5/0x12c0 kernel/smp.c:877
Code: 45 8b 2c 24 44 89 ee 83 e6 01 31 ff e8 24 e3 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 cf de 0b 00 eb 38 f3 90 <42> 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 74 1e e8 b3 de
RSP: 0018:ffffc900025a72a0 EFLAGS: 00000293
RAX: ffffffff81b9addd RBX: 1ffff110170e812d RCX: ffff88801ef9dac0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900025a73e0 R08: ffffffff901172b7 R09: 1ffffffff2022e56
R10: dffffc0000000000 R11: fffffbfff2022e57 R12: ffff8880b8740968
R13: dffffc0000000000 R14: ffff8880b863bf80 R15: 0000000000000001
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1043
__flush_tlb_multi arch/x86/include/asm/paravirt.h:57 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1382 [inline]
flush_tlb_mm_range+0x5c3/0x10c0 arch/x86/mm/tlb.c:1472
tlb_flush arch/x86/include/asm/tlb.h:23 [inline]
tlb_flush_mmu_tlbonly include/asm-generic/tlb.h:505 [inline]
tlb_flush_mmu+0x1af/0xa30 mm/mmu_gather.c:404
tlb_finish_mmu+0xf9/0x230 mm/mmu_gather.c:530
free_ldt_pgtables+0x19d/0x350 arch/x86/kernel/ldt.c:411
arch_exit_mmap arch/x86/include/asm/mmu_context.h:232 [inline]
exit_mmap+0x1af/0xa10 mm/mmap.c:1287
__mmput+0x118/0x430 kernel/fork.c:1174
exec_mmap+0x3b4/0x440 fs/exec.c:893
begin_new_exec+0x134a/0x24a0 fs/exec.c:1148
load_elf_binary+0xa47/0x2980 fs/binfmt_elf.c:1010
search_binary_handler fs/exec.c:1664 [inline]
exec_binprm fs/exec.c:1696 [inline]
bprm_execve+0x93d/0x1460 fs/exec.c:1748
do_execveat_common+0x50d/0x690 fs/exec.c:1846
__do_sys_execve fs/exec.c:1930 [inline]
__se_sys_execve fs/exec.c:1924 [inline]
__x64_sys_execve+0x97/0xc0 fs/exec.c:1924
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f42b9af6107
Code: Unable to access opcode bytes at 0x7f42b9af60dd.
RSP: 002b:00007ffca2f1dd18 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 0000559cd80f3030 RCX: 00007f42b9af6107
RDX: 0000559cd80f3050 RSI: 0000559cd80f3030 RDI: 0000559cd80f30d8
RBP: 0000559cd80f30d8 R08: 00007ffca2f1feb6 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 0000559cd80f3050
R13: 00007f42b9cbbe8b R14: 0000559cd80f3050 R15: 0000000000000000
</TASK>
Allocated by task 5824:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5219 [inline]
__kvmalloc_node_noprof+0x528/0x8a0 mm/slub.c:6711
alloc_netdev_mqs+0xa6/0x11b0 net/core/dev.c:12019
rtnl_create_link+0x31f/0xd70 net/core/rtnetlink.c:3648
rtnl_newlink_create+0x277/0xb70 net/core/rtnetlink.c:3830
__rtnl_newlink net/core/rtnetlink.c:3957 [inline]
rtnl_newlink+0x1666/0x1be0 net/core/rtnetlink.c:4072
rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6958
netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
__sys_sendto+0x709/0x7a0 net/socket.c:2206
__do_sys_sendto net/socket.c:2213 [inline]
__se_sys_sendto net/socket.c:2209 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2209
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 10761:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2687 [inline]
slab_free mm/slub.c:6124 [inline]
kfree+0x1c1/0x630 mm/slub.c:6442
device_release+0x9e/0x1d0 drivers/base/core.c:-1
kobject_cleanup lib/kobject.c:689 [inline]
kobject_release lib/kobject.c:720 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x228/0x560 lib/kobject.c:737
netdev_run_todo+0xc75/0xde0 net/core/dev.c:11720
rtnl_unlock net/core/rtnetlink.c:157 [inline]
rtnl_net_unlock include/linux/rtnetlink.h:135 [inline]
rtnl_dellink+0x6a7/0x820 net/core/rtnetlink.c:3578
rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6958
netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
____sys_sendmsg+0xa68/0xad0 net/socket.c:2592
___sys_sendmsg+0x2a5/0x360 net/socket.c:2646
__sys_sendmsg net/socket.c:2678 [inline]
__do_sys_sendmsg net/socket.c:2683 [inline]
__se_sys_sendmsg net/socket.c:2681 [inline]
__x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2681
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff888056ad6000
which belongs to the cache kmalloc-cg-4k of size 4096
The buggy address is located 16 bytes inside of
freed 4096-byte region [ffff888056ad6000, ffff888056ad7000)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x56ad0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88813fe00500 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88813fe00500 dead000000000122 0000000000000000
head: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea00015ab401 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd60c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5824, tgid 5824 (syz-executor), ts 87302067245, free_ts 25805370138
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889
prep_new_page mm/page_alloc.c:1897 [inline]
get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3962
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
alloc_slab_page mm/slub.c:3255 [inline]
allocate_slab+0x77/0x660 mm/slub.c:3444
new_slab mm/slub.c:3502 [inline]
refill_objects+0x331/0x3c0 mm/slub.c:7134
refill_sheaf mm/slub.c:2804 [inline]
__pcs_replace_empty_main+0x2b9/0x620 mm/slub.c:4578
alloc_from_pcs mm/slub.c:4681 [inline]
slab_alloc_node mm/slub.c:4815 [inline]
__do_kmalloc_node mm/slub.c:5218 [inline]
__kvmalloc_node_noprof+0x657/0x8a0 mm/slub.c:6711
alloc_netdev_mqs+0xa6/0x11b0 net/core/dev.c:12019
rtnl_create_link+0x31f/0xd70 net/core/rtnetlink.c:3648
rtnl_newlink_create+0x277/0xb70 net/core/rtnetlink.c:3830
__rtnl_newlink net/core/rtnetlink.c:3957 [inline]
rtnl_newlink+0x1666/0x1be0 net/core/rtnetlink.c:4072
rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6958
netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
__sys_sendto+0x709/0x7a0 net/socket.c:2206
page last free pid 1 tgid 1 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1433 [inline]
__free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978
__free_pages mm/page_alloc.c:5369 [inline]
free_contig_range+0xbb/0x170 mm/page_alloc.c:7373
destroy_args+0x4e5/0x570 mm/debug_vm_pgtable.c:993
debug_vm_pgtable+0x3f8/0x410 mm/debug_vm_pgtable.c:1368
do_one_initcall+0x250/0x8d0 init/main.c:1382
do_initcall_level+0x104/0x190 init/main.c:1444
do_initcalls+0x59/0xa0 init/main.c:1460
kernel_init_freeable+0x2a6/0x3e0 init/main.c:1692
kernel_init+0x1d/0x1d0 init/main.c:1582
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Memory state around the buggy address:
ffff888056ad5f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888056ad5f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888056ad6000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888056ad6080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888056ad6100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
0: 45 8b 2c 24 mov (%r12),%r13d
4: 44 89 ee mov %r13d,%esi
7: 83 e6 01 and $0x1,%esi
a: 31 ff xor %edi,%edi
c: e8 24 e3 0b 00 call 0xbe335
11: 41 83 e5 01 and $0x1,%r13d
15: 49 bd 00 00 00 00 00 movabs $0xdffffc0000000000,%r13
1c: fc ff df
1f: 75 07 jne 0x28
21: e8 cf de 0b 00 call 0xbdef5
26: eb 38 jmp 0x60
28: f3 90 pause
* 2a: 42 0f b6 04 2b movzbl (%rbx,%r13,1),%eax <-- trapping instruction
2f: 84 c0 test %al,%al
31: 75 11 jne 0x44
33: 41 f7 04 24 01 00 00 testl $0x1,(%r12)
3a: 00
3b: 74 1e je 0x5b
3d: e8 .byte 0xe8
3e: b3 de mov $0xde,%bl