Hello, syzbot found the following issue on: HEAD commit: e4fb79c7 Add linux-next specific files for 20201008 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=125c9a9f900000 kernel config: https://syzkaller.appspot.com/x/.config?x=568d41fe4341ed0f dashboard link: https://syzkaller.appspot.com/bug?extid=0796b72dc61f223d8cc5 compiler: gcc (GCC) 10.1.0-syz 20200507 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12582fe7900000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=124ac7d0500000 The issue was bisected to: commit 2ceda20f0a99a74a82b78870f3b3e5fa93087a7f Author: Christoph Hellwig <hch@xxxxxx> Date: Mon Oct 5 08:41:23 2020 +0000 scsi: core: Move command size detection out of the fast path bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=135ea777900000 final oops: https://syzkaller.appspot.com/x/report.txt?x=10dea777900000 console output: https://syzkaller.appspot.com/x/log.txt?x=175ea777900000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+0796b72dc61f223d8cc5@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 2ceda20f0a99 ("scsi: core: Move command size detection out of the fast path") 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: 6889 Comm: syz-executor086 Not tainted 5.9.0-rc8-next-20201008-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:scsi_command_size include/scsi/scsi_common.h:24 [inline] RIP: 0010:scsi_setup_scsi_cmnd drivers/scsi/scsi_lib.c:1186 [inline] RIP: 0010:scsi_prepare_cmd drivers/scsi/scsi_lib.c:1565 [inline] RIP: 0010:scsi_queue_rq+0x2155/0x3020 drivers/scsi/scsi_lib.c:1654 Code: 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 98 0c 00 00 48 8b 83 58 02 00 00 48 ba 00 00 00 00 00 fc ff df 48 89 c1 48 c1 e9 03 <0f> b6 14 11 48 89 c1 83 e1 07 38 ca 7f 08 84 d2 0f 85 53 0c 00 00 RSP: 0018:ffffc90005627580 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88801b6bd400 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffffffff84aaad82 RDI: 0000000000000003 RBP: ffff888019670000 R08: 0000000000000001 R09: ffff88801b6bd7c0 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff88801b6bd658 R14: ffff8881341bc000 R15: 0000000000000000 FS: 00007f1d217b3700(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005617bf6e4410 CR3: 000000001f08b000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: blk_mq_dispatch_rq_list+0x3a1/0x1eb0 block/blk-mq.c:1388 __blk_mq_sched_dispatch_requests+0x263/0x490 block/blk-mq-sched.c:308 blk_mq_sched_dispatch_requests+0xfb/0x180 block/blk-mq-sched.c:341 __blk_mq_run_hw_queue+0x13a/0x2d0 block/blk-mq.c:1532 __blk_mq_delay_run_hw_queue+0x522/0x5f0 block/blk-mq.c:1609 blk_mq_run_hw_queue+0x16c/0x2f0 block/blk-mq.c:1662 blk_mq_sched_insert_request+0x4d7/0x5e0 block/blk-mq-sched.c:473 blk_execute_rq+0xd4/0x1b0 block/blk-exec.c:86 sg_io+0x609/0xf50 block/scsi_ioctl.c:360 scsi_cmd_ioctl+0x5ce/0x660 block/scsi_ioctl.c:808 scsi_cmd_blk_ioctl block/scsi_ioctl.c:866 [inline] scsi_cmd_blk_ioctl+0xe1/0x130 block/scsi_ioctl.c:857 sd_ioctl_common+0x17e/0x280 drivers/scsi/sd.c:1575 sd_ioctl+0x26/0xf0 drivers/scsi/sd.c:1765 __blkdev_driver_ioctl block/ioctl.c:228 [inline] blkdev_ioctl+0x2a7/0x7f0 block/ioctl.c:623 block_ioctl+0xf9/0x140 fs/block_dev.c:1869 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl fs/ioctl.c:739 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x446059 Code: e8 fc b8 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 0f 83 0b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f1d217b2d98 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000006ddc48 RCX: 0000000000446059 RDX: 00000000200046c0 RSI: 0000000000002285 RDI: 0000000000000004 RBP: 00000000006ddc40 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006ddc4c R13: 0000000020000000 R14: 00000000004ae698 R15: 0000000000000003 Modules linked in: ---[ end trace 2bb961546eae45fe ]--- RIP: 0010:scsi_command_size include/scsi/scsi_common.h:24 [inline] RIP: 0010:scsi_setup_scsi_cmnd drivers/scsi/scsi_lib.c:1186 [inline] RIP: 0010:scsi_prepare_cmd drivers/scsi/scsi_lib.c:1565 [inline] RIP: 0010:scsi_queue_rq+0x2155/0x3020 drivers/scsi/scsi_lib.c:1654 Code: 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 98 0c 00 00 48 8b 83 58 02 00 00 48 ba 00 00 00 00 00 fc ff df 48 89 c1 48 c1 e9 03 <0f> b6 14 11 48 89 c1 83 e1 07 38 ca 7f 08 84 d2 0f 85 53 0c 00 00 RSP: 0018:ffffc90005627580 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff88801b6bd400 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffffffff84aaad82 RDI: 0000000000000003 RBP: ffff888019670000 R08: 0000000000000001 R09: ffff88801b6bd7c0 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff88801b6bd658 R14: ffff8881341bc000 R15: 0000000000000000 FS: 00007f1d217b3700(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005617bf6e4410 CR3: 000000001f08b000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 --- 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. For information about bisection process see: https://goo.gl/tpsmEJ#bisection syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches