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KASAN: slab-use-after-free Read in ipvlan_hard_header (2)

Status: closed as invalid on 2026/01/15 20:47
Subsystems: net
[Documentation on labels]
First crash: 132d, last: 48d
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-use-after-free Read in ipvlan_hard_header net 19 1 462d 462d 0/29 closed as invalid on 2025/01/15 12:30
upstream general protection fault in ipvlan_hard_header (2) net 2 1 980d 980d 0/29 closed as invalid on 2023/09/01 06:55
upstream general protection fault in ipvlan_hard_header net 2 C done error 13 1569d 2156d 0/29 closed as invalid on 2022/10/12 18:15
linux-4.19 general protection fault in ipvlan_hard_header 2 1 1593d 1593d 0/1 auto-closed as invalid on 2022/01/05 12:41

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in dev_hard_header include/linux/netdevice.h:3416 [inline]
BUG: KASAN: slab-use-after-free in ipvlan_hard_header+0xa2/0x120 drivers/net/ipvlan/ipvlan_main.c:383
Read of size 8 at addr ffff88807a458010 by task syz-executor/25452

CPU: 0 UID: 0 PID: 25452 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 dev_hard_header include/linux/netdevice.h:3416 [inline]
 ipvlan_hard_header+0xa2/0x120 drivers/net/ipvlan/ipvlan_main.c:383
 dev_hard_header include/linux/netdevice.h:3419 [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+0x580/0x6d0 net/tipc/discover.c:338
 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers kernel/time/timer.c:2373 [inline]
 __run_timer_base+0x61a/0x860 kernel/time/timer.c:2385
 run_timer_base kernel/time/timer.c:2394 [inline]
 run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2404
 handle_softirqs+0x286/0x870 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1052
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_is_held_type+0x137/0x190 kernel/locking/lockdep.c:5945
Code: 01 75 44 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 4c 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 05 09 ca 27 07 <48> 3b 44 24 08 75 43 89 d8 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f
RSP: 0000:ffffc900043a7898 EFLAGS: 00000206
RAX: 8eadba6c16e4d100 RBX: 0000000000000000 RCX: 8eadba6c16e4d100
RDX: 0000000000000000 RSI: ffffffff8d8f5ae9 RDI: ffffffff8bbf08e0
RBP: 00000000ffffffff R08: 0000000000000000 R09: ffffffff822dc13a
R10: dffffc0000000000 R11: ffffed100a8af69c R12: 0000000000000246
R13: ffff888054579e40 R14: ffffffff8df75558 R15: 0000000000000002
 lock_is_held include/linux/lockdep.h:249 [inline]
 task_css include/linux/cgroup.h:459 [inline]
 mem_cgroup_from_task+0x77/0x120 mm/memcontrol.c:884
 current_objcg_update+0x1a8/0x2c0 mm/memcontrol.c:2661
 current_obj_cgroup mm/memcontrol.c:2690 [inline]
 __memcg_kmem_charge_page+0x1f4/0x240 mm/memcontrol.c:2841
 __alloc_frozen_pages_noprof+0x1b5/0x370 mm/page_alloc.c:5195
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
 alloc_frozen_pages_noprof mm/mempolicy.c:2487 [inline]
 alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2507
 pagetable_alloc_noprof include/linux/mm.h:2987 [inline]
 __pte_alloc_one_noprof include/asm-generic/pgalloc.h:75 [inline]
 pte_alloc_one+0x23/0x310 arch/x86/mm/pgtable.c:18
 do_fault_around mm/memory.c:5668 [inline]
 do_read_fault mm/memory.c:5707 [inline]
 do_fault mm/memory.c:5850 [inline]
 do_pte_missing mm/memory.c:4362 [inline]
 handle_pte_fault mm/memory.c:6195 [inline]
 __handle_mm_fault+0x2767/0x5400 mm/memory.c:6336
 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6505
 do_user_addr_fault+0xa7c/0x1380 arch/x86/mm/fault.c:1336
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x82/0x100 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f5f5e985e93
Code: Unable to access opcode bytes at 0x7f5f5e985e69.
RSP: 002b:00007ffd5ba44ae8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f5f5e985e93
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 00005555566907d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000a459a R15: 00007ffd5ba44c80
 </TASK>

Allocated by task 16907:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417
 kasan_kmalloc include/linux/kasan.h:262 [inline]
 __do_kmalloc_node mm/slub.c:5650 [inline]
 __kvmalloc_node_noprof+0x5cd/0x910 mm/slub.c:7112
 alloc_netdev_mqs+0xa6/0x11b0 net/core/dev.c:11900
 rtnl_create_link+0x31f/0xd10 net/core/rtnetlink.c:3641
 rtnl_newlink_create+0x25c/0xb00 net/core/rtnetlink.c:3823
 __rtnl_newlink net/core/rtnetlink.c:3950 [inline]
 rtnl_newlink+0x16e4/0x1c80 net/core/rtnetlink.c:4065
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6951
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 __sys_sendto+0x3bd/0x520 net/socket.c:2244
 __do_sys_sendto net/socket.c:2251 [inline]
 __se_sys_sendto net/socket.c:2247 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2247
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 25442:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587
 kasan_save_free_info mm/kasan/kasan.h:406 [inline]
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2543 [inline]
 slab_free mm/slub.c:6642 [inline]
 kfree+0x19a/0x6d0 mm/slub.c:6849
 device_release+0x9c/0x1c0 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+0x22b/0x480 lib/kobject.c:737
 netdev_run_todo+0xd2e/0xea0 net/core/dev.c:11601
 rtnl_unlock net/core/rtnetlink.c:157 [inline]
 rtnl_net_unlock include/linux/rtnetlink.h:135 [inline]
 rtnl_dellink+0x5aa/0x700 net/core/rtnetlink.c:3571
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6951
 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x82f/0x9e0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 ____sys_sendmsg+0x505/0x830 net/socket.c:2630
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684
 __sys_sendmsg net/socket.c:2716 [inline]
 __do_sys_sendmsg net/socket.c:2721 [inline]
 __se_sys_sendmsg net/socket.c:2719 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2719
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88807a458000
 which belongs to the cache kmalloc-cg-4k of size 4096
The buggy address is located 16 bytes inside of
 freed 4096-byte region [ffff88807a458000, ffff88807a459000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7a458
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888077136081
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a030500 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000040004 00000000f5000000 ffff888077136081
head: 00fff00000000040 ffff88801a030500 dead000000000100 dead000000000122
head: 0000000000000000 0000000000040004 00000000f5000000 ffff888077136081
head: 00fff00000000003 ffffea0001e91601 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5834, tgid 5834 (syz-executor), ts 80959176365, free_ts 80913942342
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x234/0x290 mm/page_alloc.c:1845
 prep_new_page mm/page_alloc.c:1853 [inline]
 get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3879
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5178
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:3059 [inline]
 allocate_slab+0x96/0x350 mm/slub.c:3232
 new_slab mm/slub.c:3286 [inline]
 ___slab_alloc+0xf56/0x1990 mm/slub.c:4655
 __slab_alloc+0x65/0x100 mm/slub.c:4778
 __slab_alloc_node mm/slub.c:4854 [inline]
 slab_alloc_node mm/slub.c:5276 [inline]
 __do_kmalloc_node mm/slub.c:5649 [inline]
 __kmalloc_noprof+0x471/0x7f0 mm/slub.c:5662
 kmalloc_noprof include/linux/slab.h:961 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 __register_sysctl_table+0x72/0x1340 fs/proc/proc_sysctl.c:1379
 __addrconf_sysctl_register+0x328/0x4c0 net/ipv6/addrconf.c:7323
 addrconf_sysctl_register+0x168/0x1c0 net/ipv6/addrconf.c:7371
 ipv6_add_dev+0xd46/0x1370 net/ipv6/addrconf.c:460
 addrconf_notify+0x794/0x1010 net/ipv6/addrconf.c:3650
 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2267 [inline]
 call_netdevice_notifiers net/core/dev.c:2281 [inline]
 register_netdevice+0x1608/0x1ae0 net/core/dev.c:11332
 virt_wifi_newlink+0x428/0x860 drivers/net/wireless/virtual/virt_wifi.c:571
page last free pid 5821 tgid 5821 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2901
 discard_slab mm/slub.c:3330 [inline]
 __put_partials+0x146/0x170 mm/slub.c:3876
 put_cpu_partial+0x1f2/0x2e0 mm/slub.c:3951
 __slab_free+0x2b9/0x390 mm/slub.c:5929
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352
 kasan_slab_alloc include/linux/kasan.h:252 [inline]
 slab_post_alloc_hook mm/slub.c:4978 [inline]
 slab_alloc_node mm/slub.c:5288 [inline]
 __kmalloc_cache_noprof+0x36f/0x6f0 mm/slub.c:5766
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 ref_tracker_alloc+0x133/0x460 lib/ref_tracker.c:271
 __netdev_tracker_alloc include/linux/netdevice.h:4375 [inline]
 netdev_hold include/linux/netdevice.h:4404 [inline]
 netdev_queue_add_kobject net/core/net-sysfs.c:1994 [inline]
 netdev_queue_update_kobjects+0x1d1/0x6c0 net/core/net-sysfs.c:2056
 register_queue_kobjects net/core/net-sysfs.c:2119 [inline]
 netdev_register_kobject+0x258/0x310 net/core/net-sysfs.c:2362
 register_netdevice+0x126c/0x1ae0 net/core/dev.c:11294
 veth_newlink+0x5d4/0xa60 drivers/net/veth.c:1885
 rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3833
 __rtnl_newlink net/core/rtnetlink.c:3950 [inline]
 rtnl_newlink+0x16e4/0x1c80 net/core/rtnetlink.c:4065
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6951

Memory state around the buggy address:
 ffff88807a457f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807a457f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807a458000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff88807a458080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807a458100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	01 75 44             	add    %esi,0x44(%rbp)
   3:	48 c7 04 24 00 00 00 	movq   $0x0,(%rsp)
   a:	00
   b:	9c                   	pushf
   c:	8f 04 24             	pop    (%rsp)
   f:	f7 04 24 00 02 00 00 	testl  $0x200,(%rsp)
  16:	75 4c                	jne    0x64
  18:	41 f7 c4 00 02 00 00 	test   $0x200,%r12d
  1f:	74 01                	je     0x22
  21:	fb                   	sti
  22:	65 48 8b 05 09 ca 27 	mov    %gs:0x727ca09(%rip),%rax        # 0x727ca33
  29:	07
* 2a:	48 3b 44 24 08       	cmp    0x8(%rsp),%rax <-- trapping instruction
  2f:	75 43                	jne    0x74
  31:	89 d8                	mov    %ebx,%eax
  33:	48 83 c4 10          	add    $0x10,%rsp
  37:	5b                   	pop    %rbx
  38:	41 5c                	pop    %r12
  3a:	41 5d                	pop    %r13
  3c:	41 5e                	pop    %r14
  3e:	41 5f                	pop    %r15

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/30 09:56 net e5235eb6cfe0 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Read in ipvlan_hard_header
2025/10/05 05:51 net 1b54b0756f05 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Read in ipvlan_hard_header
2025/09/20 20:46 net b65678cacc03 67c37560 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Read in ipvlan_hard_header
2025/09/07 14:57 net-next c6142e1913de d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce KASAN: slab-use-after-free Read in ipvlan_hard_header
* Struck through repros no longer work on HEAD.