Hi On Tue, Mar 10, 2020 at 4:18 AM Hillf Danton <hdanton@xxxxxxxx> wrote: > On Mon, 09 Mar 2020 08:26:10 -0700 > > syzbot has found a reproducer for the following crash on: > > > > HEAD commit: 2c523b34 Linux 5.6-rc5 > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=150bce55e00000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=a5295e161cd85b82 > > dashboard link: https://syzkaller.appspot.com/bug?extid=8357fbef0d7bb602de45 > > compiler: clang version 10.0.0 (https://github.com/llvm/llvm-project/ c2443155a0fb245c8f17f2c1c72b6ea391e86e81) > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11b439c3e00000 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16dc6fb5e00000 > > > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > > Reported-by: syzbot+8357fbef0d7bb602de45@xxxxxxxxxxxxxxxxxxxxxxxxx > > > > INFO: trying to register non-static key. > > the code is fine but needs lockdep annotation. > > turning off the locking correctness validator. > > CPU: 0 PID: 10346 Comm: syz-executor364 Not tainted 5.6.0-rc5-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+0x1e9/0x30e lib/dump_stack.c:118 > > register_lock_class+0x6f4/0xec0 kernel/locking/lockdep.c:443 > > __lock_acquire+0x116/0x1bc0 kernel/locking/lockdep.c:3836 > > lock_acquire+0x154/0x250 kernel/locking/lockdep.c:4484 > > __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] > > _raw_spin_lock_irqsave+0x9e/0xc0 kernel/locking/spinlock.c:159 > > __wake_up_common_lock kernel/sched/wait.c:122 [inline] > > __wake_up+0xb8/0x150 kernel/sched/wait.c:142 > > uhid_dev_destroy drivers/hid/uhid.c:563 [inline] > > uhid_char_release+0x99/0x600 drivers/hid/uhid.c:642 > > __fput+0x2d8/0x730 fs/file_table.c:280 > > task_work_run+0x176/0x1b0 kernel/task_work.c:113 > > exit_task_work include/linux/task_work.h:22 [inline] > > do_exit+0x5ef/0x1f80 kernel/exit.c:801 > > do_group_exit+0x15e/0x2c0 kernel/exit.c:899 > > __do_sys_exit_group+0x13/0x20 kernel/exit.c:910 > > __se_sys_exit_group+0x10/0x10 kernel/exit.c:908 > > __x64_sys_exit_group+0x37/0x40 kernel/exit.c:908 > > do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:294 > > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > RIP: 0033:0x4403d8 > > Code: 00 00 be 3c 00 00 00 eb 19 66 0f 1f 84 00 00 00 00 00 48 89 d7 89 f0 0f 05 48 3d 00 f0 ff ff 77 21 f4 48 89 d7 44 89 c0 0f 05 <48> 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 0f 1f 84 00 00 00 > > RSP: 002b:00007ffd67f7d928 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 > > RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004403d8 > > RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 > > RBP: 00000000004c0d90 R08: 00000000000000e7 R09: ffffffffffffffd4 > > R10: 0000000000402570 R11: 0000000000000246 R12: 0000000000000001 > > R13: 00000000006d3180 R14: 0000000000000000 R15: 0000000000000000 > > general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN > > KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] > > CPU: 0 PID: 10346 Comm: syz-executor364 Not tainted 5.6.0-rc5-syzkaller #0 > > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > > RIP: 0010:__wake_up_common+0x297/0x4d0 kernel/sched/wait.c:86 > > Code: fb 01 00 00 45 31 f6 eb 13 66 2e 0f 1f 84 00 00 00 00 00 4d 39 fc 0f 84 e3 01 00 00 4c 89 fb 49 8d 6f e8 4c 89 f8 48 c1 e8 03 <80> 3c 10 00 74 12 48 89 df e8 eb 4e 59 00 48 ba 00 00 00 00 00 fc > > RSP: 0018:ffffc90001687c10 EFLAGS: 00010046 > > RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 > > RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff888091fe13c8 > > RBP: ffffffffffffffe8 R08: 0000000000000000 R09: ffffc90001687c78 > > R10: fffff520002d0f82 R11: 0000000000000000 R12: ffff888091fe1400 > > R13: 1ffff920002d0f8f R14: 0000000000000000 R15: 0000000000000000 > > FS: 00000000023ec940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > CR2: 0000000020000088 CR3: 0000000096b74000 CR4: 00000000001406f0 > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > Call Trace: > > __wake_up_common_lock kernel/sched/wait.c:123 [inline] > > __wake_up+0xd4/0x150 kernel/sched/wait.c:142 > > uhid_dev_destroy drivers/hid/uhid.c:563 [inline] > > uhid_char_release+0x99/0x600 drivers/hid/uhid.c:642 > > __fput+0x2d8/0x730 fs/file_table.c:280 > > task_work_run+0x176/0x1b0 kernel/task_work.c:113 > > exit_task_work include/linux/task_work.h:22 [inline] > > do_exit+0x5ef/0x1f80 kernel/exit.c:801 > > do_group_exit+0x15e/0x2c0 kernel/exit.c:899 > > __do_sys_exit_group+0x13/0x20 kernel/exit.c:910 > > __se_sys_exit_group+0x10/0x10 kernel/exit.c:908 > > __x64_sys_exit_group+0x37/0x40 kernel/exit.c:908 > > do_syscall_64+0xf3/0x1b0 arch/x86/entry/common.c:294 > > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > RIP: 0033:0x4403d8 > > Code: 00 00 be 3c 00 00 00 eb 19 66 0f 1f 84 00 00 00 00 00 48 89 d7 89 f0 0f 05 48 3d 00 f0 ff ff 77 21 f4 48 89 d7 44 89 c0 0f 05 <48> 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 0f 1f 84 00 00 00 > > RSP: 002b:00007ffd67f7d928 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 > > RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004403d8 > > RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 > > RBP: 00000000004c0d90 R08: 00000000000000e7 R09: ffffffffffffffd4 > > R10: 0000000000402570 R11: 0000000000000246 R12: 0000000000000001 > > R13: 00000000006d3180 R14: 0000000000000000 R15: 0000000000000000 > > Modules linked in: > > ---[ end trace 6b49c4c2b7708f14 ]--- > > RIP: 0010:__wake_up_common+0x297/0x4d0 kernel/sched/wait.c:86 > > Code: fb 01 00 00 45 31 f6 eb 13 66 2e 0f 1f 84 00 00 00 00 00 4d 39 fc 0f 84 e3 01 00 00 4c 89 fb 49 8d 6f e8 4c 89 f8 48 c1 e8 03 <80> 3c 10 00 74 12 48 89 df e8 eb 4e 59 00 48 ba 00 00 00 00 00 fc > > RSP: 0018:ffffc90001687c10 EFLAGS: 00010046 > > RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 > > RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff888091fe13c8 > > RBP: ffffffffffffffe8 R08: 0000000000000000 R09: ffffc90001687c78 > > R10: fffff520002d0f82 R11: 0000000000000000 R12: ffff888091fe1400 > > R13: 1ffff920002d0f8f R14: 0000000000000000 R15: 0000000000000000 > > FS: 00000000023ec940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > CR2: 0000000020000088 CR3: 0000000096b74000 CR4: 00000000001406f0 > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > > --- a/drivers/hid/uhid.c > +++ b/drivers/hid/uhid.c > @@ -639,7 +639,9 @@ static int uhid_char_release(struct inod > struct uhid_device *uhid = file->private_data; > unsigned int i; > > - uhid_dev_destroy(uhid); > + /* back off if anyone is taking care of uhid */ > + if (uhid_dev_destroy(uhid)) > + return 0; > > for (i = 0; i < UHID_BUFSIZE; ++i) > kfree(uhid->outq[i]); > That looks not correct. `uhid_dev_destroy()` returns a non-significant error code. This is only done to make sure the ioctl that call it can return a suitable code to user-space. What is this trying to fix? I am having a hard-time reading the backtrace. Thanks David
