On Tue, May 04, 2021 at 02:50:03PM -0700, ETenal wrote: > Hi, > > This is SyzScope, a research project that aims to reveal high-risk > primitives from a seemingly low-risk bug (UAF/OOB read, WARNING, BUG, etc.). > > We are currently testing seemingly low-risk bugs on syzbot's open > section(https://syzkaller.appspot.com/upstream), and try to reach out to > kernel developers as long as SyzScope discovers any high-risk primitives. > > Please let us know if SyzScope indeed helps, and any suggestions/feedback. > > Regrading the bug "KASAN: use-after-free Read in hci_chan_del", SyzScope > reports 3 memory write capability. > > The detailed comments can be found at https://sites.google.com/view/syzscope/kasan-use-after-free-read-in-hci_chan_del > I don't understand what you are saying at all. This looks like a normal syzbot email. Are you saying that part of it generated by SyzScope? I don't think there is anyone who thinks a UAF/OOB read is low impact. There are no comments at the "detailed comments" URL. regards, dan carpenter > On 8/2/2020 1:45 PM, syzbot wrote: > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit: ac3a0c84 Merge git://git.kernel.org/pub/scm/linux/kernel/g.. > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=11b8d570900000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=e59ee776d5aa8d55 > > dashboard link: https://syzkaller.appspot.com/bug?extid=305a91e025a73e4fd6ce > > compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11f7ceea900000 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17e5de04900000 > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > Reported-by: syzbot+305a91e025a73e4fd6ce@xxxxxxxxxxxxxxxxxxxxxxxxx > > > > IPVS: ftp: loaded support on port[0] = 21 > > ================================================================== > > BUG: KASAN: use-after-free in hci_chan_del+0x33/0x130 net/bluetooth/hci_conn.c:1707 > > Read of size 8 at addr ffff8880a9591f18 by task syz-executor081/6793 > > > > CPU: 0 PID: 6793 Comm: syz-executor081 Not tainted 5.8.0-rc7-syzkaller #0 > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > > Call Trace: > > __dump_stack lib/dump_stack.c:77 [inline] > > dump_stack+0x1f0/0x31e lib/dump_stack.c:118 > > print_address_description+0x66/0x5a0 mm/kasan/report.c:383 > > __kasan_report mm/kasan/report.c:513 [inline] > > kasan_report+0x132/0x1d0 mm/kasan/report.c:530 > > hci_chan_del+0x33/0x130 net/bluetooth/hci_conn.c:1707 > > l2cap_conn_del+0x4c2/0x650 net/bluetooth/l2cap_core.c:1900 > > hci_disconn_cfm include/net/bluetooth/hci_core.h:1355 [inline] > > hci_conn_hash_flush+0x127/0x200 net/bluetooth/hci_conn.c:1536 > > hci_dev_do_close+0xb7b/0x1040 net/bluetooth/hci_core.c:1761 > > hci_unregister_dev+0x16d/0x1590 net/bluetooth/hci_core.c:3606 > > vhci_release+0x73/0xc0 drivers/bluetooth/hci_vhci.c:340 > > __fput+0x2f0/0x750 fs/file_table.c:281 > > task_work_run+0x137/0x1c0 kernel/task_work.c:135 > > exit_task_work include/linux/task_work.h:25 [inline] > > do_exit+0x601/0x1f80 kernel/exit.c:805 > > do_group_exit+0x161/0x2d0 kernel/exit.c:903 > > __do_sys_exit_group+0x13/0x20 kernel/exit.c:914 > > __se_sys_exit_group+0x10/0x10 kernel/exit.c:912 > > __x64_sys_exit_group+0x37/0x40 kernel/exit.c:912 > > do_syscall_64+0x73/0xe0 arch/x86/entry/common.c:384 > > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > > RIP: 0033:0x444fe8 > > Code: Bad RIP value. > > RSP: 002b:00007ffe96e46e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 > > RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000444fe8 > > RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001 > > RBP: 00000000004ccdd0 R08: 00000000000000e7 R09: ffffffffffffffd0 > > R10: 00007f5ee25cd700 R11: 0000000000000246 R12: 0000000000000001 > > R13: 00000000006e0200 R14: 0000000000000000 R15: 0000000000000000 > > > > Allocated by task 6821: > > save_stack mm/kasan/common.c:48 [inline] > > set_track mm/kasan/common.c:56 [inline] > > __kasan_kmalloc+0x103/0x140 mm/kasan/common.c:494 > > kmem_cache_alloc_trace+0x234/0x300 mm/slab.c:3551 > > kmalloc include/linux/slab.h:555 [inline] > > kzalloc include/linux/slab.h:669 [inline] > > hci_chan_create+0x9a/0x270 net/bluetooth/hci_conn.c:1692 > > l2cap_conn_add+0x66/0xb00 net/bluetooth/l2cap_core.c:7699 > > l2cap_connect_cfm+0xdb/0x12b0 net/bluetooth/l2cap_core.c:8097 > > hci_connect_cfm include/net/bluetooth/hci_core.h:1340 [inline] > > hci_remote_features_evt net/bluetooth/hci_event.c:3210 [inline] > > hci_event_packet+0x1164c/0x18260 net/bluetooth/hci_event.c:6061 > > hci_rx_work+0x236/0x9c0 net/bluetooth/hci_core.c:4705 > > process_one_work+0x789/0xfc0 kernel/workqueue.c:2269 > > worker_thread+0xaa4/0x1460 kernel/workqueue.c:2415 > > kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234 > > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 > > > > Freed by task 1530: > > save_stack mm/kasan/common.c:48 [inline] > > set_track mm/kasan/common.c:56 [inline] > > kasan_set_free_info mm/kasan/common.c:316 [inline] > > __kasan_slab_free+0x114/0x170 mm/kasan/common.c:455 > > __cache_free mm/slab.c:3426 [inline] > > kfree+0x10a/0x220 mm/slab.c:3757 > > hci_disconn_loglink_complete_evt net/bluetooth/hci_event.c:4999 [inline] > > hci_event_packet+0x304e/0x18260 net/bluetooth/hci_event.c:6188 > > hci_rx_work+0x236/0x9c0 net/bluetooth/hci_core.c:4705 > > process_one_work+0x789/0xfc0 kernel/workqueue.c:2269 > > worker_thread+0xaa4/0x1460 kernel/workqueue.c:2415 > > kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234 > > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 > > > > The buggy address belongs to the object at ffff8880a9591f00 > > which belongs to the cache kmalloc-128 of size 128 > > The buggy address is located 24 bytes inside of > > 128-byte region [ffff8880a9591f00, ffff8880a9591f80) > > The buggy address belongs to the page: > > page:ffffea0002a56440 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880a9591800 > > flags: 0xfffe0000000200(slab) > > raw: 00fffe0000000200 ffffea0002a5a648 ffffea00028a4a08 ffff8880aa400700 > > raw: ffff8880a9591800 ffff8880a9591000 000000010000000a 0000000000000000 > > page dumped because: kasan: bad access detected > > > > Memory state around the buggy address: > > ffff8880a9591e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ffff8880a9591e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > > > ffff8880a9591f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ^ > > ffff8880a9591f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > > ffff8880a9592000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc > > ================================================================== > > > > > > --- > > This report is generated by a bot. It may contain errors. > > See https://goo.gl/tpsmEJ for more information about syzbot. > > syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. > > > > syzbot will keep track of this issue. See: > > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > > syzbot can test patches for this issue, for details see: > > https://goo.gl/tpsmEJ#testing-patches > > > > -- > You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/c2004663-e54a-7fbc-ee19-b2749549e2dd%40gmail.com.
