Hello, syzbot found the following issue on: HEAD commit: 5ee96fa9 Merge tag 'irq-urgent-2021-03-21' of git://git.ke.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=17fb84bed00000 kernel config: https://syzkaller.appspot.com/x/.config?x=6abda3336c698a07 dashboard link: https://syzkaller.appspot.com/bug?extid=283ce5a46486d6acdbaf Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+283ce5a46486d6acdbaf@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:71 [inline] BUG: KASAN: null-ptr-deref in atomic64_read include/asm-generic/atomic-instrumented.h:837 [inline] BUG: KASAN: null-ptr-deref in atomic_long_read include/asm-generic/atomic-long.h:29 [inline] BUG: KASAN: null-ptr-deref in filp_close+0x22/0x170 fs/open.c:1289 Read of size 8 at addr 0000000000000077 by task syz-executor.4/16965 CPU: 0 PID: 16965 Comm: syz-executor.4 Not tainted 5.12.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 __kasan_report mm/kasan/report.c:403 [inline] kasan_report.cold+0x5f/0xd8 mm/kasan/report.c:416 check_region_inline mm/kasan/generic.c:180 [inline] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:186 instrument_atomic_read include/linux/instrumented.h:71 [inline] atomic64_read include/asm-generic/atomic-instrumented.h:837 [inline] atomic_long_read include/asm-generic/atomic-long.h:29 [inline] filp_close+0x22/0x170 fs/open.c:1289 close_files fs/file.c:403 [inline] put_files_struct fs/file.c:418 [inline] put_files_struct+0x1d0/0x350 fs/file.c:415 exit_files+0x7e/0xa0 fs/file.c:435 do_exit+0xbc2/0x2a60 kernel/exit.c:820 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x42c/0x2100 kernel/signal.c:2773 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:789 handle_signal_work kernel/entry/common.c:147 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:208 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x466459 Code: Unable to access opcode bytes at RIP 0x46642f. RSP: 002b:00007feb5e334218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000056bf68 RCX: 0000000000466459 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000056bf68 RBP: 000000000056bf60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf6c R13: 0000000000a9fb1f R14: 00007feb5e334300 R15: 0000000000022000 ================================================================== --- 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.