================================================================== BUG: KASAN: slab-out-of-bounds in __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] BUG: KASAN: slab-out-of-bounds in _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 Read of size 1 at addr ffff88805be7ef40 by task swapper/1/0 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.15.0-rc4-syzkaller-00042-gb6ea1680d0ac #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xb4/0x290 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 __kasan_check_byte+0x2a/0x40 mm/kasan/common.c:557 kasan_check_byte include/linux/kasan.h:399 [inline] lock_acquire+0x8d/0x360 kernel/locking/lockdep.c:5840 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] br_multicast_port_group_expired+0x6a/0x710 net/bridge/br_multicast.c:865 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1789 expire_timers kernel/time/timer.c:1840 [inline] __run_timers kernel/time/timer.c:2414 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2426 run_timer_base kernel/time/timer.c:2435 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2445 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 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 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:81 Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 03 4b 19 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197de0 EFLAGS: 000002c6 RAX: b19330702c3bd800 RBX: ffffffff81973cc8 RCX: b19330702c3bd800 RDX: 0000000000000001 RSI: ffffffff8d73674f RDI: ffffffff8bc0fa60 RBP: ffffc90000197f20 R08: ffff8880b8932b5b R09: 1ffff1101712656b R10: dffffc0000000000 R11: ffffed101712656c R12: ffffffff8f7daa70 R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110038dbb40 arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:748 default_idle_call+0x74/0xb0 kernel/sched/idle.c:117 cpuidle_idle_call kernel/sched/idle.c:185 [inline] do_idle+0x1e8/0x510 kernel/sched/idle.c:325 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:423 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x147 Allocated by task 16355: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4341 [inline] __kmalloc_noprof+0x27a/0x4f0 mm/slub.c:4353 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] ops_init+0x7b/0x5c0 net/core/net_namespace.c:128 setup_net+0x238/0x830 net/core/net_namespace.c:364 copy_net_ns+0x32e/0x590 net/core/net_namespace.c:518 create_new_namespaces+0x3d3/0x700 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:228 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3375 __do_sys_unshare kernel/fork.c:3446 [inline] __se_sys_unshare kernel/fork.c:3444 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3444 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88805be7ec00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 400 bytes to the right of allocated 432-byte region [ffff88805be7ec00, ffff88805be7edb0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5be7c head: order:2 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 ffff88801a041c80 ffffea0000a37a00 dead000000000002 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801a041c80 ffffea0000a37a00 dead000000000002 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea00016f9f01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 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 36, tgid 36 (kworker/u8:2), ts 86119048935, free_ts 28164974479 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1718 prep_new_page mm/page_alloc.c:1726 [inline] get_page_from_freelist+0x21c7/0x22a0 mm/page_alloc.c:3688 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2468 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2632 new_slab mm/slub.c:2686 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3872 __slab_alloc mm/slub.c:3962 [inline] __slab_alloc_node mm/slub.c:4037 [inline] slab_alloc_node mm/slub.c:4198 [inline] __do_kmalloc_node mm/slub.c:4340 [inline] __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4353 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] fib6_info_alloc+0x30/0xf0 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x4b3/0x1360 net/ipv6/route.c:3802 ip6_route_add+0x28/0x160 net/ipv6/route.c:3896 addrconf_add_mroute net/ipv6/addrconf.c:2551 [inline] addrconf_add_dev+0x24f/0x340 net/ipv6/addrconf.c:2569 addrconf_dev_config net/ipv6/addrconf.c:3480 [inline] addrconf_init_auto_addrs+0x674/0xb80 net/ipv6/addrconf.c:3568 addrconf_notify+0xacc/0x1010 net/ipv6/addrconf.c:3741 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 netif_state_change+0x284/0x3a0 net/core/dev.c:1530 linkwatch_do_dev+0x117/0x170 net/core/link_watch.c:186 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:1262 [inline] __free_frozen_pages+0xb05/0xcd0 mm/page_alloc.c:2725 __free_pages mm/page_alloc.c:5080 [inline] free_contig_range+0x159/0x440 mm/page_alloc.c:6936 destroy_args+0x86/0x460 mm/debug_vm_pgtable.c:1017 debug_vm_pgtable+0x3cf/0x410 mm/debug_vm_pgtable.c:1397 do_one_initcall+0x233/0x820 init/main.c:1257 do_initcall_level+0x137/0x1f0 init/main.c:1319 do_initcalls+0x69/0xd0 init/main.c:1335 kernel_init_freeable+0x3d9/0x570 init/main.c:1567 kernel_init+0x1d/0x1d0 init/main.c:1457 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff88805be7ee00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805be7ee80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805be7ef00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88805be7ef80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805be7f000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: cc int3 1: cc int3 2: cc int3 3: cc int3 4: cc int3 5: cc int3 6: cc int3 7: 90 nop 8: 90 nop 9: 90 nop a: 90 nop b: 90 nop c: 90 nop d: 90 nop e: 90 nop f: 90 nop 10: 90 nop 11: 90 nop 12: 90 nop 13: 90 nop 14: 90 nop 15: 90 nop 16: 90 nop 17: f3 0f 1e fa endbr64 1b: 66 90 xchg %ax,%ax 1d: 0f 00 2d 03 4b 19 00 verw 0x194b03(%rip) # 0x194b27 24: f3 0f 1e fa endbr64 28: fb sti 29: f4 hlt * 2a: c3 ret <-- trapping instruction 2b: cc int3 2c: cc int3 2d: cc int3 2e: cc int3 2f: cc int3 30: cc int3 31: cc int3 32: cc int3 33: cc int3 34: cc int3 35: cc int3 36: cc int3 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop