syzbot

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BUG: KASAN: slab-use-after-free in inet6_addr_del+0x60c/0x650 net/ipv6/addrconf.c:3147
Read of size 4 at addr ffff88805c94d46c by task dhcpcd/5494

CPU: 1 UID: 0 PID: 5494 Comm: dhcpcd Not tainted 6.13.0-rc7-syzkaller-00149-g9bffa1ad25b8 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:489
 kasan_report+0x143/0x180 mm/kasan/report.c:602
 inet6_addr_del+0x60c/0x650 net/ipv6/addrconf.c:3147
 inet6_rtm_deladdr+0x292/0x350 net/ipv6/addrconf.c:4820
 rtnetlink_rcv_msg+0x741/0xcf0 net/core/rtnetlink.c:6931
 netlink_rcv_skb+0x1e5/0x430 net/netlink/af_netlink.c:2542
 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
 netlink_unicast+0x7f8/0x990 net/netlink/af_netlink.c:1347
 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891
 sock_sendmsg_nosec net/socket.c:711 [inline]
 __sock_sendmsg+0x223/0x270 net/socket.c:726
 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583
 ___sys_sendmsg net/socket.c:2637 [inline]
 __sys_sendmsg+0x269/0x350 net/socket.c:2669
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f12275daa4b
Code: ff 89 ef 48 89 04 24 e8 22 56 f9 ff 48 8b 04 24 48 83 c4 20 5d c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6d 48 8b 15 ae c3 0c 00 f7 d8 64 89 02 48 83
RSP: 002b:00007fff108f52e8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f12275026c0 RCX: 00007f12275daa4b
RDX: 0000000000000000 RSI: 00007fff10909498 RDI: 0000000000000030
RBP: 0000000000000030 R08: 0000000000000000 R09: 00007fff10909498
R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff
R13: 00007fff10909498 R14: 000000000000002c R15: 0000000000000001
 </TASK>

Allocated by task 5494:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x243/0x390 mm/slub.c:4329
 kmalloc_noprof include/linux/slab.h:901 [inline]
 kzalloc_noprof include/linux/slab.h:1037 [inline]
 ipv6_add_addr+0x580/0x1090 net/ipv6/addrconf.c:1114
 inet6_addr_add+0x563/0xb00 net/ipv6/addrconf.c:3080
 inet6_rtm_newaddr+0x8a4/0xc80 net/ipv6/addrconf.c:5065
 rtnetlink_rcv_msg+0x741/0xcf0 net/core/rtnetlink.c:6931
 netlink_rcv_skb+0x1e5/0x430 net/netlink/af_netlink.c:2542
 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
 netlink_unicast+0x7f8/0x990 net/netlink/af_netlink.c:1347
 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891
 sock_sendmsg_nosec net/socket.c:711 [inline]
 __sock_sendmsg+0x223/0x270 net/socket.c:726
 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583
 ___sys_sendmsg net/socket.c:2637 [inline]
 __sys_sendmsg+0x269/0x350 net/socket.c:2669
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 6007:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2353 [inline]
 slab_free_freelist_hook mm/slub.c:2382 [inline]
 slab_free_bulk mm/slub.c:4637 [inline]
 kmem_cache_free_bulk+0x2d8/0x530 mm/slub.c:5001
 kfree_bulk include/linux/slab.h:790 [inline]
 kvfree_rcu_bulk+0x24b/0x4e0 kernel/rcu/tree.c:3385
 kvfree_rcu_drain_ready kernel/rcu/tree.c:3569 [inline]
 kfree_rcu_monitor+0x8fd/0x990 kernel/rcu/tree.c:3642
 process_one_work kernel/workqueue.c:3236 [inline]
 process_scheduled_works+0xa68/0x1840 kernel/workqueue.c:3317
 worker_thread+0x870/0xd30 kernel/workqueue.c:3398
 kthread+0x2f2/0x390 kernel/kthread.c:389
 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:544
 kvfree_call_rcu+0xfc/0x790 kernel/rcu/tree.c:3820
 in6_ifa_put include/net/addrconf.h:434 [inline]
 ipv6_del_addr+0x808/0x9b0 net/ipv6/addrconf.c:1343
 inet6_addr_del+0x443/0x650 net/ipv6/addrconf.c:3145
 inet6_rtm_deladdr+0x292/0x350 net/ipv6/addrconf.c:4820
 rtnetlink_rcv_msg+0x741/0xcf0 net/core/rtnetlink.c:6931
 netlink_rcv_skb+0x1e5/0x430 net/netlink/af_netlink.c:2542
 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
 netlink_unicast+0x7f8/0x990 net/netlink/af_netlink.c:1347
 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1891
 sock_sendmsg_nosec net/socket.c:711 [inline]
 __sock_sendmsg+0x223/0x270 net/socket.c:726
 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583
 ___sys_sendmsg net/socket.c:2637 [inline]
 __sys_sendmsg+0x269/0x350 net/socket.c:2669
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Second to last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:544
 insert_work+0x3e/0x330 kernel/workqueue.c:2183
 __queue_work+0xc8b/0xf50 kernel/workqueue.c:2339
 call_timer_fn+0x189/0x650 kernel/time/timer.c:1793
 expire_timers kernel/time/timer.c:1839 [inline]
 __run_timers kernel/time/timer.c:2418 [inline]
 __run_timer_base+0x695/0x8e0 kernel/time/timer.c:2430
 run_timer_base kernel/time/timer.c:2439 [inline]
 run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2449
 handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:561
 __do_softirq kernel/softirq.c:595 [inline]
 invoke_softirq kernel/softirq.c:435 [inline]
 __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

The buggy address belongs to the object at ffff88805c94d400
 which belongs to the cache kmalloc-cg-512 of size 512
The buggy address is located 108 bytes inside of
 freed 512-byte region [ffff88805c94d400, ffff88805c94d600)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5c94c
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888058640a01
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801ac4f140 ffffea000128c300 dead000000000002
raw: 0000000000000000 0000000000100010 00000001f5000000 ffff888058640a01
head: 00fff00000000040 ffff88801ac4f140 ffffea000128c300 dead000000000002
head: 0000000000000000 0000000000100010 00000001f5000000 ffff888058640a01
head: 00fff00000000002 ffffea0001725301 ffffffffffffffff 0000000000000000
head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 8304, tgid 8303 (syz.5.654), ts 302588379122, free_ts 302265924769
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1558
 prep_new_page mm/page_alloc.c:1566 [inline]
 get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3476
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4753
 alloc_pages_mpol_noprof+0x3e1/0x780 mm/mempolicy.c:2269
 alloc_slab_page+0x6a/0x110 mm/slub.c:2423
 allocate_slab+0x5a/0x2b0 mm/slub.c:2589
 new_slab mm/slub.c:2642 [inline]
 ___slab_alloc+0xc27/0x14a0 mm/slub.c:3830
 __slab_alloc+0x58/0xa0 mm/slub.c:3920
 __slab_alloc_node mm/slub.c:3995 [inline]
 slab_alloc_node mm/slub.c:4156 [inline]
 __do_kmalloc_node mm/slub.c:4297 [inline]
 __kmalloc_node_track_caller_noprof+0x2e9/0x4c0 mm/slub.c:4317
 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:609
 __alloc_skb+0x1f3/0x440 net/core/skbuff.c:678
 alloc_skb include/linux/skbuff.h:1323 [inline]
 alloc_skb_with_frags+0xc3/0x820 net/core/skbuff.c:6612
 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2884
 unix_dgram_sendmsg+0x6d3/0x1f80 net/unix/af_unix.c:2027
 sock_sendmsg_nosec net/socket.c:711 [inline]
 __sock_sendmsg+0x223/0x270 net/socket.c:726
 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583
page last free pid 8312 tgid 8312 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_page+0xd3f/0x1010 mm/page_alloc.c:2659
 __slab_free+0x2c2/0x380 mm/slub.c:4524
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4119 [inline]
 slab_alloc_node mm/slub.c:4168 [inline]
 kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4175
 getname_flags+0xb7/0x540 fs/namei.c:139
 do_sys_openat2+0xd2/0x1d0 fs/open.c:1396
 do_sys_open fs/open.c:1417 [inline]
 __do_sys_openat fs/open.c:1433 [inline]
 __se_sys_openat fs/open.c:1428 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1428
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88805c94d300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805c94d380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88805c94d400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                          ^
 ffff88805c94d480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805c94d500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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