================================================================== BUG: KASAN: global-out-of-bounds in fib6_clean_node+0x51c/0x5b0 net/ipv6/ip6_fib.c:2251 Read of size 8 at addr ffffffff9b2233a8 by task syz.6.3100/15809 CPU: 3 UID: 0 PID: 15809 Comm: syz.6.3100 Not tainted 6.15.0-syzkaller-12426-ge271ed52b344 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xcd/0x680 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 fib6_clean_node+0x51c/0x5b0 net/ipv6/ip6_fib.c:2251 fib6_walk_continue+0x44f/0x8d0 net/ipv6/ip6_fib.c:2177 fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2225 fib6_clean_tree+0xd4/0x110 net/ipv6/ip6_fib.c:2305 __fib6_clean_all+0x107/0x2d0 net/ipv6/ip6_fib.c:2321 rt6_sync_down_dev net/ipv6/route.c:5004 [inline] rt6_disable_ip+0x2ec/0x990 net/ipv6/route.c:5009 addrconf_ifdown.isra.0+0x11d/0x1a90 net/ipv6/addrconf.c:3857 addrconf_notify+0x220/0x19e0 net/ipv6/addrconf.c:3780 notifier_call_chain+0xbc/0x410 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:2230 call_netdevice_notifiers_extack net/core/dev.c:2268 [inline] call_netdevice_notifiers net/core/dev.c:2282 [inline] unregister_netdevice_many_notify+0xf9d/0x2700 net/core/dev.c:12077 unregister_netdevice_many net/core/dev.c:12140 [inline] unregister_netdevice_queue+0x305/0x3f0 net/core/dev.c:11984 unregister_netdevice include/linux/netdevice.h:3379 [inline] __tun_detach+0x1249/0x1540 drivers/net/tun.c:620 tun_detach drivers/net/tun.c:636 [inline] tun_chr_close+0xc2/0x230 drivers/net/tun.c:3396 __fput+0x402/0xb70 fs/file_table.c:465 task_work_run+0x14d/0x240 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x864/0x2bd0 kernel/exit.c:955 do_group_exit+0xd3/0x2a0 kernel/exit.c:1104 get_signal+0x2673/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] irqentry_exit_to_user_mode+0x12a/0x270 kernel/entry/common.c:184 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7fb39464f837 Code: Unable to access opcode bytes at 0x7fb39464f80d. RSP: 002b:00007fffda0b1aa0 EFLAGS: 00010206 RAX: 0000000000000000 RBX: 000000000000000b RCX: ffffe00000000000 RDX: 00007fffda0b1ac0 RSI: 00007fffda0b1bf0 RDI: 000000000000000b RBP: 00007fb3949b7ba0 R08: 00007fb394600000 R09: 000000000000000f R10: 0000000000000001 R11: 0000000000000006 R12: 00007fb3949b5fac R13: 00007fb3949b5fa0 R14: fffffffffffffffe R15: 00007fffda1b00c0 The buggy address belongs to the variable: binder_devices+0x8/0x40 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1b223 flags: 0xfff00000002000(reserved|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000002000 ffffea00006c88c8 ffffea00006c88c8 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner info is not present (never set?) Memory state around the buggy address: ffffffff9b223280: f9 f9 f9 f9 00 f9 f9 f9 f9 f9 f9 f9 00 f9 f9 f9 ffffffff9b223300: f9 f9 f9 f9 00 f9 f9 f9 f9 f9 f9 f9 00 f9 f9 f9 >ffffffff9b223380: f9 f9 f9 f9 00 f9 f9 f9 f9 f9 f9 f9 00 f9 f9 f9 ^ ffffffff9b223400: f9 f9 f9 f9 00 00 f9 f9 f9 f9 f9 f9 00 f9 f9 f9 ffffffff9b223480: f9 f9 f9 f9 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================