IPv6: ADDRCONF(NETDEV_UP): batadv_slave_1: link is not ready batman_adv: batadv0: Interface activated: batadv_slave_1 IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready ================================================================== BUG: KASAN: use-after-free in perf_output_read_group kernel/events/core.c:5895 [inline] BUG: KASAN: use-after-free in perf_output_read+0x118d/0x1500 kernel/events/core.c:5930 Read of size 8 at addr ffff8881db0e35a0 by task syz-executor262/31435 CPU: 1 PID: 31435 Comm: syz-executor262 Not tainted 4.14.209-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x14b/0x1f1 lib/dump_stack.c:58 print_address_description.cold.6+0x9/0x1ca mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report.cold.7+0x11a/0x2d4 mm/kasan/report.c:409 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 perf_output_read_group kernel/events/core.c:5895 [inline] perf_output_read+0x118d/0x1500 kernel/events/core.c:5930 perf_output_sample+0x128c/0x1930 kernel/events/core.c:5972 __perf_event_output kernel/events/core.c:6285 [inline] perf_event_output_forward+0x103/0x1d0 kernel/events/core.c:6298 __perf_event_overflow+0x107/0x300 kernel/events/core.c:7547 perf_swevent_overflow+0x165/0x210 kernel/events/core.c:7623 perf_swevent_event+0x1f5/0x2f0 kernel/events/core.c:7656 do_perf_sw_event kernel/events/core.c:7764 [inline] ___perf_sw_event+0x26b/0x3f0 kernel/events/core.c:7795 __perf_sw_event+0x3c/0x60 kernel/events/core.c:7807 perf_sw_event include/linux/perf_event.h:1046 [inline] __do_page_fault+0x648/0xb10 arch/x86/mm/fault.c:1483 do_page_fault+0x64/0x3fb arch/x86/mm/fault.c:1517 page_fault+0x25/0x50 arch/x86/entry/entry_64.S:1123 RIP: 0010:copy_user_enhanced_fast_string+0xe/0x20 arch/x86/lib/copy_user_64.S:181 RSP: 0018:ffff8881d3abf928 EFLAGS: 00010206 RAX: 0000000000000000 RBX: 0000000020f45acb RCX: 0000000000007acb RDX: 0000000000008000 RSI: 0000000020f46000 RDI: ffff8881c4d80535 RBP: ffff8881d3abf950 R08: 0000000000000000 R09: 0000000000000200 R10: ffffed10389b0fff R11: ffff8881c4d87fff R12: ffff8881c4d80000 R13: ffff8881d87f4680 R14: ffff8881d3abfdb0 R15: ffff8881d3abfd60 _copy_from_iter_full+0x166/0x760 lib/iov_iter.c:608 copy_from_iter_full include/linux/uio.h:126 [inline] skb_do_copy_data_nocache include/net/sock.h:1889 [inline] skb_copy_to_page_nocache include/net/sock.h:1915 [inline] tcp_sendmsg_locked+0xa02/0x3be0 net/ipv4/tcp.c:1360 tcp_sendmsg+0x27/0x40 net/ipv4/tcp.c:1457 inet_sendmsg+0x108/0x440 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:656 SYSC_sendto net/socket.c:1763 [inline] SyS_sendto+0x1e4/0x2c0 net/socket.c:1731 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x449899 RSP: 002b:00007f7b90e6eda8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000006dec48 RCX: 0000000000449899 RDX: ffffffffffffffef RSI: 0000000020d7cfcb RDI: 0000000000000004 RBP: 00000000006dec40 R08: 0000000000000000 R09: 0000000000000053 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dec4c R13: 00007fffb682584f R14: 00007f7b90e6f9c0 R15: 0000000000000064 Allocated by task 31349: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc.part.1+0x62/0xf0 mm/kasan/kasan.c:551 kasan_kmalloc+0xaf/0xc0 mm/kasan/kasan.c:536 kmem_cache_alloc_trace+0x152/0x3f0 mm/slab.c:3618 kmalloc include/linux/slab.h:488 [inline] kzalloc include/linux/slab.h:661 [inline] alloc_perf_context+0x43/0xd0 kernel/events/core.c:3865 find_get_context.isra.49+0x108/0x510 kernel/events/core.c:3954 SYSC_perf_event_open kernel/events/core.c:10179 [inline] SyS_perf_event_open+0x689/0x2100 kernel/events/core.c:10010 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 31361: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xab/0x190 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xcc/0x270 mm/slab.c:3815 free_ctx+0x41/0x50 kernel/events/core.c:1152 __rcu_reclaim kernel/rcu/rcu.h:195 [inline] rcu_do_batch kernel/rcu/tree.c:2699 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline] __rcu_process_callbacks kernel/rcu/tree.c:2929 [inline] rcu_process_callbacks+0x7a5/0x11e0 kernel/rcu/tree.c:2946 __do_softirq+0x246/0x9b5 kernel/softirq.c:288 The buggy address belongs to the object at ffff8881db0e3540 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 96 bytes inside of 512-byte region [ffff8881db0e3540, ffff8881db0e3740) The buggy address belongs to the page: page:ffffea00076c38c0 count:1 mapcount:0 mapping:ffff8881db0e3040 index:0x0 flags: 0x17ffe0000000100(slab) raw: 017ffe0000000100 ffff8881db0e3040 0000000000000000 0000000100000006 raw: ffffea00076dd6e0 ffffea00079b8ca0 ffff8881f6000940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8881db0e3480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8881db0e3500: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff8881db0e3580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881db0e3600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881db0e3680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================