program syz.8.7706 is using a deprecated SCSI ioctl, please convert it to SG_IO ------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: lib/refcount.c:25 at refcount_warn_saturate+0x111/0x130 lib/refcount.c:25, CPU#0: syz.8.7706/1740 Modules linked in: CPU: 0 UID: 0 PID: 1740 Comm: syz.8.7706 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:refcount_warn_saturate+0x111/0x130 lib/refcount.c:25 Code: 06 e8 d3 83 09 fd 48 8d 3d 2c 15 e5 0b 67 48 0f b9 3a e8 c2 83 09 fd 5b 5d c3 cc cc cc cc e8 b6 83 09 fd 48 8d 3d 1f 15 e5 0b <67> 48 0f b9 3a e8 a5 83 09 fd 5b 5d c3 cc cc cc cc 48 89 df e8 16 RSP: 0018:ffffc900069078c0 EFLAGS: 00010287 RAX: 00000000000028c5 RBX: ffff88802dca5e10 RCX: ffffc90029e01000 RDX: 0000000000080000 RSI: ffffffff84ffdb6a RDI: ffffffff90e4f090 RBP: 0000000000000002 R08: 0000000000000005 R09: 0000000000000004 R10: 0000000000000002 R11: 0000000000000000 R12: ffff88802cdff880 R13: ffff888057ab6010 R14: ffff88802e5d55b8 R15: ffff88802dca5e10 FS: 00007f8211d776c0(0000) GS:ffff8880d631a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c341cef CR3: 000000005a91a000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 00000000fda3b69a DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __refcount_add include/linux/refcount.h:289 [inline] __refcount_inc include/linux/refcount.h:366 [inline] refcount_inc include/linux/refcount.h:383 [inline] kref_get include/linux/kref.h:45 [inline] dvb_device_get drivers/media/dvb-core/dvbdev.c:621 [inline] dvb_device_open+0x304/0x3b0 drivers/media/dvb-core/dvbdev.c:106 chrdev_open+0x234/0x6a0 fs/char_dev.c:411 do_dentry_open+0x6ab/0x14d0 fs/open.c:947 vfs_open+0x82/0x3f0 fs/open.c:1079 do_open fs/namei.c:4700 [inline] path_openat+0x2873/0x4280 fs/namei.c:4859 do_file_open+0x20e/0x430 fs/namei.c:4888 do_sys_openat2+0x10f/0x1e0 fs/open.c:1395 do_sys_open fs/open.c:1401 [inline] __do_sys_openat fs/open.c:1417 [inline] __se_sys_openat fs/open.c:1412 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1412 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8210f5d68e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007f8211d76b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f8211d776c0 RCX: 00007f8210f5d68e RDX: 0000000000000002 RSI: 00007f8211d76c00 RDI: ffffffffffffff9c RBP: 00007f8211d76c00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd R13: 00007f8211216038 R14: 00007f8211215fa0 R15: 00007ffcae9b4608 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: e8 d3 83 09 fd call 0xfd0983d8 5: 48 8d 3d 2c 15 e5 0b lea 0xbe5152c(%rip),%rdi # 0xbe51538 c: 67 48 0f b9 3a ud1 (%edx),%rdi 11: e8 c2 83 09 fd call 0xfd0983d8 16: 5b pop %rbx 17: 5d pop %rbp 18: c3 ret 19: cc int3 1a: cc int3 1b: cc int3 1c: cc int3 1d: e8 b6 83 09 fd call 0xfd0983d8 22: 48 8d 3d 1f 15 e5 0b lea 0xbe5151f(%rip),%rdi # 0xbe51548 * 29: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2e: e8 a5 83 09 fd call 0xfd0983d8 33: 5b pop %rbx 34: 5d pop %rbp 35: c3 ret 36: cc int3 37: cc int3 38: cc int3 39: cc int3 3a: 48 89 df mov %rbx,%rdi 3d: e8 .byte 0xe8 3e: 16 (bad)