Hello, syzbot found the following issue on: HEAD commit: c6d7e3b385f1 Add linux-next specific files for 20220616 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=10d9fb1bf00000 kernel config: https://syzkaller.appspot.com/x/.config?x=9d495405e4a98620 dashboard link: https://syzkaller.appspot.com/bug?extid=4d875b4d2e2b60bae9b4 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 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+4d875b4d2e2b60bae9b4@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read include/linux/instrumented.h:71 [inline] BUG: KASAN: null-ptr-deref in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] BUG: KASAN: null-ptr-deref in hugepage_vma_check+0x8e/0x750 mm/huge_memory.c:82 Read of size 8 at addr 00000000000005a8 by task syz-executor.5/21978 CPU: 0 PID: 21978 Comm: syz-executor.5 Not tainted 5.19.0-rc2-next-20220616-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 kasan_report+0xbe/0x1f0 mm/kasan/report.c:495 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] hugepage_vma_check+0x8e/0x750 mm/huge_memory.c:82 show_smap+0x1c6/0x470 fs/proc/task_mmu.c:866 traverse.part.0+0xcf/0x5f0 fs/seq_file.c:111 traverse fs/seq_file.c:101 [inline] seq_read_iter+0x90f/0x1280 fs/seq_file.c:195 seq_read+0x337/0x4b0 fs/seq_file.c:162 do_loop_readv_writev fs/read_write.c:763 [inline] do_loop_readv_writev fs/read_write.c:750 [inline] do_iter_read+0x4f8/0x750 fs/read_write.c:805 vfs_readv+0xe5/0x150 fs/read_write.c:923 do_preadv fs/read_write.c:1015 [inline] __do_sys_preadv fs/read_write.c:1065 [inline] __se_sys_preadv fs/read_write.c:1060 [inline] __x64_sys_preadv+0x22b/0x310 fs/read_write.c:1060 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7f5c1d889109 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5c1ea69168 EFLAGS: 00000246 ORIG_RAX: 0000000000000127 RAX: ffffffffffffffda RBX: 00007f5c1d99bf60 RCX: 00007f5c1d889109 RDX: 0000000000000001 RSI: 00000000200006c0 RDI: 0000000000000005 RBP: 00007f5c1d8e305d R08: 0000000000000000 R09: 0000000000000000 R10: 00000000fffffffe R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd8514b43f R14: 00007f5c1ea69300 R15: 0000000000022000 </TASK> ================================================================== --- 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.