syzbot


KASAN: out-of-bounds Read in perf_output_read

Status: auto-closed as invalid on 2020/11/03 15:55
Reported-by: syzbot+04cc755f1cdba84875fd@syzkaller.appspotmail.com
First crash: 723d, last: 723d

Sample crash report:
==================================================================
BUG: KASAN: out-of-bounds in perf_output_read_group kernel/events/core.c:5888 [inline]
BUG: KASAN: out-of-bounds in perf_output_read+0xe24/0xf80 kernel/events/core.c:5923
Read of size 8 at addr ffff888091511e08 by task syz-executor.5/12777

CPU: 0 PID: 12777 Comm: syz-executor.5 Not tainted 4.14.184-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+0x1b2/0x283 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1dc mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0xa9/0x2b9 mm/kasan/report.c:393
 perf_output_read_group kernel/events/core.c:5888 [inline]
 perf_output_read+0xe24/0xf80 kernel/events/core.c:5923
 perf_output_sample+0x1196/0x1720 kernel/events/core.c:5965
 __perf_event_output kernel/events/core.c:6278 [inline]
 perf_event_output_forward+0xf8/0x1f0 kernel/events/core.c:6291
 __perf_event_overflow+0x113/0x310 kernel/events/core.c:7536
 perf_swevent_overflow+0x17b/0x210 kernel/events/core.c:7612
 perf_swevent_event+0x19c/0x270 kernel/events/core.c:7645
 do_perf_sw_event kernel/events/core.c:7753 [inline]
 ___perf_sw_event+0x295/0x480 kernel/events/core.c:7784
 __perf_sw_event+0x42/0x80 kernel/events/core.c:7796
 perf_sw_event include/linux/perf_event.h:1046 [inline]
 __do_page_fault+0x6c1/0xb50 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:ffff88804f8ffa88 EFLAGS: 00010206
RAX: 0000000000000000 RBX: 0000000000008000 RCX: 0000000000007acb
RDX: 0000000000008000 RSI: 0000000020f66000 RDI: ffff88803ad90535
RBP: 0000000020f65acb R08: ffffed10075b3000 R09: 0000000000000000
R10: ffffed10075b2fff R11: ffff88803ad97fff R12: ffff88803ad90000
R13: 00007ffffffff000 R14: 0000000020f6dacb R15: ffff88803ad90000
 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+0x195/0x680 lib/iov_iter.c:608
 copy_from_iter_full include/linux/uio.h:126 [inline]
 skb_do_copy_data_nocache include/net/sock.h:1886 [inline]
 skb_copy_to_page_nocache include/net/sock.h:1912 [inline]
 tcp_sendmsg_locked+0x249d/0x2ef0 net/ipv4/tcp.c:1360
 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1457
 inet_sendmsg+0x116/0x4d0 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: 0033:0x45cb29
RSP: 002b:00007f8dbd1c3c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000502b80 RCX: 000000000045cb29
RDX: ffffffffffffffef RSI: 0000000020d7cfcb RDI: 0000000000000006
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0f0000000000e814
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000a51 R14: 00000000004cd36a R15: 00007f8dbd1c46d4

Allocated by task 12776:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc.part.0+0x4f/0xd0 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.isra.0+0x35/0xd0 net/core/skbuff.c:137
 pskb_expand_head+0x115/0xc90 net/core/skbuff.c:1462
 __skb_pad+0x1f6/0x5d0 net/core/skbuff.c:1638
 __skb_put_padto include/linux/skbuff.h:3009 [inline]
 skb_put_padto include/linux/skbuff.h:3028 [inline]
 send_hsr_supervision_frame+0xc2b/0xf00 net/hsr/hsr_device.c:318
 hsr_announce+0xf0/0x330 net/hsr/hsr_device.c:350
 call_timer_fn+0x14a/0x650 kernel/time/timer.c:1279
 expire_timers+0x233/0x4d0 kernel/time/timer.c:1318
 __run_timers kernel/time/timer.c:1636 [inline]
 run_timer_softirq+0x1d8/0x5b0 kernel/time/timer.c:1649
 __do_softirq+0x254/0x9bf kernel/softirq.c:288

Freed by task 11916:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xaf/0x190 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kfree+0xcb/0x260 mm/slab.c:3815
 __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+0x78d/0x1180 kernel/rcu/tree.c:2946
 __do_softirq+0x254/0x9bf kernel/softirq.c:288

The buggy address belongs to the object at ffff888091511d00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 264 bytes inside of
 512-byte region [ffff888091511d00, ffff888091511f00)
The buggy address belongs to the page:
page:ffffea0002454440 count:1 mapcount:0 mapping:ffff888091511080 index:0xffff888091511800
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffff888091511080 ffff888091511800 0000000100000002
raw: ffffea00023a20a0 ffffea00025b9b60 ffff8880aa800940 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888091511d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888091511d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888091511e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                         ^
 ffff888091511e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888091511f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-14 2020/07/06 15:54 linux-4.14.y b850307b279c ac5a135b .config log report