Hello, syzbot found the following issue on: HEAD commit: 372b2891c15a Add linux-next specific files for 20210824 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=15dc8389300000 kernel config: https://syzkaller.appspot.com/x/.config?x=18ce42745c8b0dd6 dashboard link: https://syzkaller.appspot.com/bug?extid=f74aa89114a236643919 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=10979275300000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10fe84a9300000 The issue was bisected to: commit 45938335d0a9773d65a82a7ca722bb76e4b997a8 Author: Christoph Hellwig <hch@xxxxxx> Date: Mon Aug 16 13:19:03 2021 +0000 st: do not allocate a gendisk bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14682399300000 final oops: https://syzkaller.appspot.com/x/report.txt?x=16682399300000 console output: https://syzkaller.appspot.com/x/log.txt?x=12682399300000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+f74aa89114a236643919@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 45938335d0a9 ("st: do not allocate a gendisk") 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: 6540 Comm: syz-executor323 Not tainted 5.14.0-rc7-next-20210824-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:strncpy+0x32/0xb0 lib/string.c:130 Code: 54 55 53 48 83 ec 08 48 85 d2 74 5c 4c 8d 2c 17 48 89 fb 49 bc 00 00 00 00 00 fc ff df 48 89 f0 48 89 f2 48 c1 e8 03 83 e2 07 <42> 0f b6 04 20 38 d0 7f 04 84 c0 75 41 48 89 d8 48 89 da 0f b6 2e RSP: 0018:ffffc90002d2fb98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffc90002d2fc70 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc90002d2fc70 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffc90002d2fcb7 R10: ffffffff817c66f5 R11: 0000000000000000 R12: dffffc0000000000 R13: ffffc90002d2fc90 R14: ffffc90002d2fc70 R15: ffffc90002d2fc94 FS: 0000000001ff3300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5c7fb696c0 CR3: 000000001ae25000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: strncpy include/linux/fortify-string.h:59 [inline] do_blk_trace_setup+0x113/0xcd0 kernel/trace/blktrace.c:485 __blk_trace_setup+0xca/0x180 kernel/trace/blktrace.c:589 blk_trace_setup+0x43/0x60 kernel/trace/blktrace.c:607 sg_ioctl_common drivers/scsi/sg.c:1122 [inline] sg_ioctl+0x252/0x2760 drivers/scsi/sg.c:1164 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 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: 0033:0x4434b9 Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 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 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd335501e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004004a0 RCX: 00000000004434b9 RDX: 0000000020000100 RSI: 00000000c0481273 RDI: 0000000000000004 RBP: 0000000000403060 R08: 00000000004004a0 R09: 00000000004004a0 R10: 002367732f766564 R11: 0000000000000246 R12: 00000000004030f0 R13: 0000000000000000 R14: 00000000004b1018 R15: 00000000004004a0 Modules linked in: ---[ end trace c8de7dc978626109 ]--- RIP: 0010:strncpy+0x32/0xb0 lib/string.c:130 Code: 54 55 53 48 83 ec 08 48 85 d2 74 5c 4c 8d 2c 17 48 89 fb 49 bc 00 00 00 00 00 fc ff df 48 89 f0 48 89 f2 48 c1 e8 03 83 e2 07 <42> 0f b6 04 20 38 d0 7f 04 84 c0 75 41 48 89 d8 48 89 da 0f b6 2e RSP: 0018:ffffc90002d2fb98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffc90002d2fc70 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc90002d2fc70 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffc90002d2fcb7 R10: ffffffff817c66f5 R11: 0000000000000000 R12: dffffc0000000000 R13: ffffc90002d2fc90 R14: ffffc90002d2fc70 R15: ffffc90002d2fc94 FS: 0000000001ff3300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8125f40018 CR3: 000000001ae25000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 54 push %rsp 1: 55 push %rbp 2: 53 push %rbx 3: 48 83 ec 08 sub $0x8,%rsp 7: 48 85 d2 test %rdx,%rdx a: 74 5c je 0x68 c: 4c 8d 2c 17 lea (%rdi,%rdx,1),%r13 10: 48 89 fb mov %rdi,%rbx 13: 49 bc 00 00 00 00 00 movabs $0xdffffc0000000000,%r12 1a: fc ff df 1d: 48 89 f0 mov %rsi,%rax 20: 48 89 f2 mov %rsi,%rdx 23: 48 c1 e8 03 shr $0x3,%rax 27: 83 e2 07 and $0x7,%edx * 2a: 42 0f b6 04 20 movzbl (%rax,%r12,1),%eax <-- trapping instruction 2f: 38 d0 cmp %dl,%al 31: 7f 04 jg 0x37 33: 84 c0 test %al,%al 35: 75 41 jne 0x78 37: 48 89 d8 mov %rbx,%rax 3a: 48 89 da mov %rbx,%rdx 3d: 0f b6 2e movzbl (%rsi),%ebp --- 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
