================================================================== BUG: KASAN: slab-use-after-free in br_multicast_port_group_expired+0x4c0/0x550 net/bridge/br_multicast.c:861 Read of size 8 at addr ffff888071d6d000 by task syz.5.1232/9699 CPU: 1 PID: 9699 Comm: syz.5.1232 Not tainted 6.10.0-rc5-syzkaller-00021-g24ca36a562d6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report+0xd9/0x110 mm/kasan/report.c:601 br_multicast_port_group_expired+0x4c0/0x550 net/bridge/br_multicast.c:861 call_timer_fn+0x1a3/0x610 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers+0x74b/0xaf0 kernel/time/timer.c:2417 __run_timer_base kernel/time/timer.c:2428 [inline] __run_timer_base kernel/time/timer.c:2421 [inline] run_timer_base+0x111/0x190 kernel/time/timer.c:2437 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2447 handle_softirqs+0x219/0x8f0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0xbb/0x120 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:finish_task_switch.isra.0+0x220/0xcc0 kernel/sched/core.c:5282 Code: a9 0a 00 00 44 8b 0d 17 b0 85 0e 45 85 c9 0f 85 c0 01 00 00 48 89 df e8 ae f8 ff ff e8 b9 da 36 00 fb 65 48 8b 1d a0 3d a4 7e <48> 8d bb f8 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 RSP: 0018:ffffc90004177d18 EFLAGS: 00000206 RAX: 00000000000085f5 RBX: ffff888028bf8000 RCX: 1ffffffff1fc9ac1 RDX: 0000000000000000 RSI: ffffffff8b2cc140 RDI: ffffffff8b9024c0 RBP: ffffc90004177d60 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff8fe51897 R11: 0000000000000000 R12: ffff8880b933f938 R13: ffff888028bf9e00 R14: 0000000000000000 R15: ffff8880b933ebc0 context_switch kernel/sched/core.c:5411 [inline] __schedule+0xf1d/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 exit_to_user_mode_loop kernel/entry/common.c:102 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0xde/0x280 kernel/entry/common.c:231 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0033:0x7fd43064cb94 Code: 0f 82 b9 00 00 00 48 39 f2 72 6e 41 0f 11 0c 24 48 8b 77 f8 48 89 f8 48 89 eb eb 12 66 2e 0f 1f 84 00 00 00 00 00 48 8b 4b 08 <48> 83 c3 08 48 39 d1 72 f3 48 83 e8 08 48 39 f2 73 17 66 2e 0f 1f RSP: 002b:00007ffc97d21a80 EFLAGS: 00000293 RAX: 00007fd42fab7e40 RBX: 00007fd42fa86f98 RCX: ffffffff88b96ebe RDX: ffffffff88b9717d RSI: ffffffff88b97253 RDI: 00007fd42fac5e28 RBP: 00007fd42fa7b318 R08: 00007fd42faa0898 R09: 0000000000000008 R10: 0000000088ba1cfe R11: 0000000088ba1d02 R12: 00007fd42fa7b310 R13: 000000000000001f R14: 00007fd42fa01008 R15: 00007fd430904140 Allocated by task 6702: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387 kmalloc_noprof include/linux/slab.h:660 [inline] kzalloc_noprof include/linux/slab.h:778 [inline] new_nbp net/bridge/br_if.c:431 [inline] br_add_if+0x427/0x1b80 net/bridge/br_if.c:599 do_set_master+0x1bf/0x230 net/core/rtnetlink.c:2701 do_setlink+0xcaf/0x3ff0 net/core/rtnetlink.c:2907 __rtnl_newlink+0xc35/0x1960 net/core/rtnetlink.c:3696 rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3743 rtnetlink_rcv_msg+0x3ca/0xea0 net/core/rtnetlink.c:6635 netlink_rcv_skb+0x16e/0x440 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x545/0x820 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x482/0x4e0 net/socket.c:2192 __do_sys_sendto net/socket.c:2204 [inline] __se_sys_sendto net/socket.c:2200 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2200 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 9700: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579 poison_slab_object+0xf7/0x160 mm/kasan/common.c:240 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2196 [inline] slab_free mm/slub.c:4437 [inline] kfree+0x12a/0x3b0 mm/slub.c:4558 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1fd/0x5b0 lib/kobject.c:737 rcu_do_batch kernel/rcu/tree.c:2535 [inline] rcu_core+0x82b/0x16b0 kernel/rcu/tree.c:2809 handle_softirqs+0x219/0x8f0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0xbb/0x120 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 Last potentially related work creation: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 __kasan_record_aux_stack+0xba/0xd0 mm/kasan/generic.c:541 __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:3072 br_dev_delete+0x99/0x1a0 net/bridge/br_if.c:386 br_net_exit_batch_rtnl+0x116/0x1f0 net/bridge/br.c:369 cleanup_net+0x54b/0xbf0 net/core/net_namespace.c:633 process_one_work+0x9c8/0x1b40 kernel/workqueue.c:3248 process_scheduled_works kernel/workqueue.c:3329 [inline] worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409 kthread+0x2c4/0x3a0 kernel/kthread.c:389 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 The buggy address belongs to the object at ffff888071d6d000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 0 bytes inside of freed 1024-byte region [ffff888071d6d000, ffff888071d6d400) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x71d68 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffefff(slab) raw: 00fff00000000040 ffff888015441dc0 0000000000000000 dead000000000001 raw: 0000000000000000 0000000080100010 00000001ffffefff 0000000000000000 head: 00fff00000000040 ffff888015441dc0 0000000000000000 dead000000000001 head: 0000000000000000 0000000080100010 00000001ffffefff 0000000000000000 head: 00fff00000000003 ffffea0001c75a01 ffffffffffffffff 0000000000000000 head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 1096, tgid 1096 (kworker/u8:8), ts 118658703752, free_ts 118015241497 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1468 prep_new_page mm/page_alloc.c:1476 [inline] get_page_from_freelist+0x136a/0x2e50 mm/page_alloc.c:3420 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4678 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page+0x56/0x110 mm/slub.c:2265 allocate_slab mm/slub.c:2428 [inline] new_slab+0x84/0x260 mm/slub.c:2481 ___slab_alloc+0xdac/0x1870 mm/slub.c:3667 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3757 __slab_alloc_node mm/slub.c:3810 [inline] slab_alloc_node mm/slub.c:3989 [inline] __do_kmalloc_node mm/slub.c:4121 [inline] kmalloc_node_track_caller_noprof+0x355/0x430 mm/slub.c:4142 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:597 __alloc_skb+0x164/0x380 net/core/skbuff.c:666 alloc_skb include/linux/skbuff.h:1308 [inline] nlmsg_new include/net/netlink.h:1015 [inline] inet6_rt_notify+0xf0/0x2b0 net/ipv6/route.c:6182 fib6_del_route net/ipv6/ip6_fib.c:2012 [inline] fib6_del+0xf08/0x17b0 net/ipv6/ip6_fib.c:2047 fib6_clean_node+0x426/0x5b0 net/ipv6/ip6_fib.c:2209 fib6_walk_continue+0x452/0x8d0 net/ipv6/ip6_fib.c:2131 fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2179 fib6_clean_tree+0xd7/0x120 net/ipv6/ip6_fib.c:2259 page last free pid 5094 tgid 5094 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1088 [inline] free_unref_page+0x64a/0xe40 mm/page_alloc.c:2583 __put_partials+0x14c/0x170 mm/slub.c:2995 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4e/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x192/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:322 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3941 [inline] slab_alloc_node mm/slub.c:4001 [inline] __do_kmalloc_node mm/slub.c:4121 [inline] __kmalloc_node_noprof+0x1c7/0x440 mm/slub.c:4129 kmalloc_node_noprof include/linux/slab.h:681 [inline] __vmalloc_area_node mm/vmalloc.c:3628 [inline] __vmalloc_node_range_noprof+0x401/0x1520 mm/vmalloc.c:3823 __vmalloc_node_noprof mm/vmalloc.c:3888 [inline] vzalloc_noprof+0x6b/0x90 mm/vmalloc.c:3961 alloc_counters net/ipv6/netfilter/ip6_tables.c:815 [inline] copy_entries_to_user net/ipv6/netfilter/ip6_tables.c:837 [inline] get_entries net/ipv6/netfilter/ip6_tables.c:1039 [inline] do_ip6t_get_ctl+0x6ba/0xaf0 net/ipv6/netfilter/ip6_tables.c:1677 nf_getsockopt+0x7c/0xe0 net/netfilter/nf_sockopt.c:116 ipv6_getsockopt+0x1fd/0x2c0 net/ipv6/ipv6_sockglue.c:1494 tcp_getsockopt+0xa1/0x100 net/ipv4/tcp.c:4406 do_sock_getsockopt+0x2e8/0x760 net/socket.c:2374 __sys_getsockopt+0x1a1/0x270 net/socket.c:2403 __do_sys_getsockopt net/socket.c:2413 [inline] __se_sys_getsockopt net/socket.c:2410 [inline] __x64_sys_getsockopt+0xbd/0x160 net/socket.c:2410 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 Memory state around the buggy address: ffff888071d6cf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888071d6cf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888071d6d000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888071d6d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888071d6d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ------------[ cut here ]------------ UBSAN: array-index-out-of-bounds in kernel/locking/qspinlock.c:131:9 index 15933 is out of range for type 'long unsigned int [8]' CPU: 1 PID: 9699 Comm: syz.5.1232 Tainted: G B 6.10.0-rc5-syzkaller-00021-g24ca36a562d6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:114 ubsan_epilogue lib/ubsan.c:231 [inline] __ubsan_handle_out_of_bounds+0x110/0x150 lib/ubsan.c:429 decode_tail kernel/locking/qspinlock.c:131 [inline] __pv_queued_spin_lock_slowpath+0xcb2/0xcc0 kernel/locking/qspinlock.c:468 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:584 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:114 [inline] do_raw_spin_lock+0x210/0x2c0 kernel/locking/spinlock_debug.c:116 spin_lock include/linux/spinlock.h:351 [inline] br_multicast_port_group_expired+0x70/0x550 net/bridge/br_multicast.c:865 call_timer_fn+0x1a3/0x610 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers+0x74b/0xaf0 kernel/time/timer.c:2417 __run_timer_base kernel/time/timer.c:2428 [inline] __run_timer_base kernel/time/timer.c:2421 [inline] run_timer_base+0x111/0x190 kernel/time/timer.c:2437 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2447 handle_softirqs+0x219/0x8f0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0xbb/0x120 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:finish_task_switch.isra.0+0x220/0xcc0 kernel/sched/core.c:5282 Code: a9 0a 00 00 44 8b 0d 17 b0 85 0e 45 85 c9 0f 85 c0 01 00 00 48 89 df e8 ae f ---------------- Code disassembly (best guess): 0: a9 0a 00 00 44 test $0x4400000a,%eax 5: 8b 0d 17 b0 85 0e mov 0xe85b017(%rip),%ecx # 0xe85b022 b: 45 85 c9 test %r9d,%r9d e: 0f 85 c0 01 00 00 jne 0x1d4 14: 48 89 df mov %rbx,%rdi 17: e8 ae f8 ff ff call 0xfffff8ca 1c: e8 b9 da 36 00 call 0x36dada 21: fb sti 22: 65 48 8b 1d a0 3d a4 mov %gs:0x7ea43da0(%rip),%rbx # 0x7ea43dca 29: 7e * 2a: 48 8d bb f8 15 00 00 lea 0x15f8(%rbx),%rdi <-- trapping instruction 31: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 38: fc ff df 3b: 48 89 fa mov %rdi,%rdx 3e: 48 rex.W 3f: c1 .byte 0xc1