On Fri, Mar 26, 2021 at 8:55 AM syzbot <syzbot+283ce5a46486d6acd...@syzkaller.appspotmail.com> wrote: > > 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+283ce5a46486d6acd...@syzkaller.appspotmail.com
I was able to reproduce this with the following C program: https://gist.githubusercontent.com/dvyukov/00fb7aae489f22c60b4e64b45ef14d60/raw/cb368ca523d01986c2917f4414add0893b8f4243/gistfile1.txt +Christian The repro also contains close_range as the previous similar crash: https://syzkaller.appspot.com/bug?id=1bef50bdd9622a1969608d1090b2b4a588d0c6ac I don't know if it's related or not in this case, but looks suspicious. > ================================================================== > 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 syzkal...@googlegroups.com. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > > -- > 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+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/syzkaller-bugs/00000000000069c40405be6bdad4%40google.com.