Hello, syzbot found the following issue on: HEAD commit: aa14a3016182 Add linux-next specific files for 20210910 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=148da295300000 kernel config: https://syzkaller.appspot.com/x/.config?x=e400f2d70a0ed309 dashboard link: https://syzkaller.appspot.com/bug?extid=74a15f02ccb51f398601 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.1 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12da37b9300000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10bb87ed300000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+74a15f02ccb51f398601@xxxxxxxxxxxxxxxxxxxxxxxxx general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 6638 Comm: syz-executor038 Not tainted 5.14.0-next-20210910-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:get_fuse_conn_super fs/fuse/fuse_i.h:844 [inline] RIP: 0010:fuse_test_super+0x68/0xa0 fs/fuse/inode.c:1633 Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 3a 48 8b 9b 78 06 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 75 12 31 c0 48 39 2b 5b 5d 0f 94 c0 c3 e8 92 9f 0d ff RSP: 0018:ffffc90002e1fcc8 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff82ae91fd RDI: ffff8880750a4678 RBP: ffff88801ca4d000 R08: 0000000000000001 R09: 0000000000000003 R10: fffff520005c3f8e R11: 0000000000000000 R12: dffffc0000000000 R13: ffffffff82ae91f0 R14: 0000000000000000 R15: 0000000000000002 FS: 0000000000fd5300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd112d1758 CR3: 0000000071247000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sget_fc+0x1ff/0x7c0 fs/super.c:525 fuse_get_tree+0x201/0x3f0 fs/fuse/inode.c:1664 vfs_get_tree+0x89/0x2f0 fs/super.c:1498 do_new_mount fs/namespace.c:2988 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3318 do_mount fs/namespace.c:3331 [inline] __do_sys_mount fs/namespace.c:3539 [inline] __se_sys_mount fs/namespace.c:3516 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3516 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+0x44/0xae RIP: 0033:0x440089 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 90 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd112d1778 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000000483088 RCX: 0000000000440089 RDX: 0000000020002100 RSI: 00000000200020c0 RDI: 0000000000000000 RBP: 0030656c69662f2e R08: 00000000200004c0 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000010bf1 R13: 00007ffd112d178c R14: 00007ffd112d17a0 R15: 00007ffd112d1790 Modules linked in: ---[ end trace 750f18e3bec431c4 ]--- RIP: 0010:get_fuse_conn_super fs/fuse/fuse_i.h:844 [inline] RIP: 0010:fuse_test_super+0x68/0xa0 fs/fuse/inode.c:1633 Code: 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 3a 48 8b 9b 78 06 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 75 12 31 c0 48 39 2b 5b 5d 0f 94 c0 c3 e8 92 9f 0d ff RSP: 0018:ffffc90002e1fcc8 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff82ae91fd RDI: ffff8880750a4678 RBP: ffff88801ca4d000 R08: 0000000000000001 R09: 0000000000000003 R10: fffff520005c3f8e R11: 0000000000000000 R12: dffffc0000000000 R13: ffffffff82ae91f0 R14: 0000000000000000 R15: 0000000000000002 FS: 0000000000fd5300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd112d1758 CR3: 0000000071247000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 4 bytes skipped: 0: df 48 89 fisttps -0x77(%rax) 3: fa cli 4: 48 c1 ea 03 shr $0x3,%rdx 8: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) c: 75 3a jne 0x48 e: 48 8b 9b 78 06 00 00 mov 0x678(%rbx),%rbx 15: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 1c: fc ff df 1f: 48 89 da mov %rbx,%rdx 22: 48 c1 ea 03 shr $0x3,%rdx * 26: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2a: 75 12 jne 0x3e 2c: 31 c0 xor %eax,%eax 2e: 48 39 2b cmp %rbp,(%rbx) 31: 5b pop %rbx 32: 5d pop %rbp 33: 0f 94 c0 sete %al 36: c3 retq 37: e8 92 9f 0d ff callq 0xff0d9fce --- 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
