================================================================== BUG: KASAN: use-after-free in primary_event_id kernel/events/core.c:1316 [inline] BUG: KASAN: use-after-free in perf_output_read_group kernel/events/core.c:5897 [inline] BUG: KASAN: use-after-free in perf_output_read+0x1046/0x1090 kernel/events/core.c:5932 Read of size 8 at addr ffff8880a26038a0 by task syz-executor.5/14702 CPU: 1 PID: 14702 Comm: syz-executor.5 Not tainted 4.14.277-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+0x1b2/0x281 lib/dump_stack.c:58 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252 kasan_report_error.cold+0x8a/0x191 mm/kasan/report.c:351 kasan_report mm/kasan/report.c:409 [inline] __asan_report_load8_noabort+0x68/0x70 mm/kasan/report.c:430 primary_event_id kernel/events/core.c:1316 [inline] perf_output_read_group kernel/events/core.c:5897 [inline] perf_output_read+0x1046/0x1090 kernel/events/core.c:5932 perf_output_sample+0xa28/0x16f0 kernel/events/core.c:5974 __perf_event_output kernel/events/core.c:6287 [inline] perf_event_output_forward+0xf8/0x1f0 kernel/events/core.c:6300 __perf_event_overflow+0x113/0x310 kernel/events/core.c:7549 perf_swevent_overflow kernel/events/core.c:7625 [inline] perf_swevent_event+0x299/0x460 kernel/events/core.c:7653 do_perf_sw_event kernel/events/core.c:7766 [inline] ___perf_sw_event+0x2a1/0x480 kernel/events/core.c:7797 __perf_sw_event+0x4f/0x100 kernel/events/core.c:7809 perf_sw_event include/linux/perf_event.h:1046 [inline] __do_page_fault+0x692/0xad0 arch/x86/mm/fault.c:1483 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:ffff88806f03fa60 EFLAGS: 00050202 RAX: ffffed100df618ab RBX: 0000000000004553 RCX: 000000000000101e RDX: 0000000000004553 RSI: 0000000020f11000 RDI: ffff88806fb0b535 RBP: 0000000020f0dacb R08: 0000000000000001 R09: ffffed100df618aa R10: ffff88806fb0c552 R11: 0000000000000000 R12: ffff88806fb08000 R13: 00007ffffffff000 R14: 0000000020f1201e R15: ffff8880ab098140 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:55 [inline] copyin+0x99/0xc0 lib/iov_iter.c:146 _copy_from_iter_full+0x19c/0x760 lib/iov_iter.c:610 copy_from_iter_full include/linux/uio.h:126 [inline] skb_do_copy_data_nocache include/net/sock.h:1892 [inline] skb_copy_to_page_nocache include/net/sock.h:1918 [inline] tcp_sendmsg_locked+0x23fc/0x2ef0 net/ipv4/tcp.c:1360 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1457 inet_sendmsg+0x11a/0x4e0 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xb5/0x100 net/socket.c:656 SYSC_sendto net/socket.c:1763 [inline] SyS_sendto+0x1c7/0x2c0 net/socket.c:1731 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7ffa100590e9 RSP: 002b:00007ffa0e9ce168 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007ffa1016bf60 RCX: 00007ffa100590e9 RDX: ffffffffffffffef RSI: 0000000020d7cfcb RDI: 0000000000000006 RBP: 00007ffa100b308d R08: 0000000000000000 R09: 0000000000000053 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff57ea765f R14: 00007ffa0e9ce300 R15: 0000000000022000 Allocated by task 4627: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551 __do_kmalloc_node mm/slab.c:3682 [inline] __kmalloc_node_track_caller+0x4c/0x70 mm/slab.c:3696 __kmalloc_reserve net/core/skbuff.c:137 [inline] __alloc_skb+0x96/0x510 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:980 [inline] kobject_uevent_env+0x882/0xf30 lib/kobject_uevent.c:480 kobject_synth_uevent+0x5b6/0x6d0 lib/kobject_uevent.c:205 uevent_store+0x21/0x60 drivers/base/core.c:1020 dev_attr_store+0x56/0x80 drivers/base/core.c:738 sysfs_kf_write+0x106/0x160 fs/sysfs/file.c:142 kernfs_fop_write+0x289/0x440 fs/kernfs/file.c:316 __vfs_write+0xe4/0x630 fs/read_write.c:480 vfs_write+0x17f/0x4d0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb Freed by task 4627: save_stack mm/kasan/kasan.c:447 [inline] set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0xc3/0x1a0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kfree+0xc9/0x250 mm/slab.c:3815 skb_free_head net/core/skbuff.c:563 [inline] skb_release_data+0x5f6/0x820 net/core/skbuff.c:583 skb_release_all net/core/skbuff.c:640 [inline] __kfree_skb net/core/skbuff.c:654 [inline] consume_skb+0xe0/0x380 net/core/skbuff.c:714 netlink_broadcast_filtered+0x2ae/0x9e0 net/netlink/af_netlink.c:1498 kobject_uevent_env+0x9c8/0xf30 lib/kobject_uevent.c:496 kobject_synth_uevent+0x5b6/0x6d0 lib/kobject_uevent.c:205 uevent_store+0x21/0x60 drivers/base/core.c:1020 dev_attr_store+0x56/0x80 drivers/base/core.c:738 sysfs_kf_write+0x106/0x160 fs/sysfs/file.c:142 kernfs_fop_write+0x289/0x440 fs/kernfs/file.c:316 __vfs_write+0xe4/0x630 fs/read_write.c:480 vfs_write+0x17f/0x4d0 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xf2/0x210 fs/read_write.c:582 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb The buggy address belongs to the object at ffff8880a2603840 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 96 bytes inside of 512-byte region [ffff8880a2603840, ffff8880a2603a40) The buggy address belongs to the page: page:ffffea00028980c0 count:1 mapcount:0 mapping:ffff8880a26030c0 index:0xffff8880a26030c0 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffff8880a26030c0 ffff8880a26030c0 0000000100000005 raw: ffffea00026759a0 ffffea00024464a0 ffff88813fe74940 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a2603780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880a2603800: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff8880a2603880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a2603900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a2603980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================