program: r0 = socket$can_j1939(0x1d, 0x2, 0x7) ioctl$ifreq_SIOCGIFINDEX_vcan(r0, 0x8933, &(0x7f0000000040)={'vxcan0\x00', 0x0}) bind$can_j1939(r0, &(0x7f0000000080)={0x1d, r1}, 0x18) r2 = socket$can_j1939(0x1d, 0x2, 0x7) ioctl$ifreq_SIOCGIFINDEX_vcan(r2, 0x8933, &(0x7f00000000c0)={'vxcan1\x00', 0x0}) bind$can_j1939(r2, &(0x7f0000000100)={0x1d, r3}, 0x18) connect$can_j1939(r2, &(0x7f0000000140)={0x1d, r3}, 0x18) sendmsg$can_j1939(r2, &(0x7f0000000180)={0x0, 0x0, &(0x7f00000001c0)={&(0x7f0000000200)='data', 0x4}}, 0x0) recvmsg$can_j1939(r0, &(0x7f0000000240)={0x0, 0x0, &(0x7f0000000280)=[{&(0x7f00000002c0)=""/4, 0x4}], 0x1}, 0x0) [ 59.570302][ T4675] Bluetooth: hci0: command tx timeout [ 59.589992][ T5327] ------------[ cut here ]------------ [ 59.592216][ T5327] refcount_t: underflow; use-after-free. [ 59.594619][ T5327] WARNING: CPU: 0 PID: 5327 at lib/refcount.c:28 refcount_warn_saturate+0x15a/0x1d0 [ 59.598132][ T5327] Modules linked in: [ 59.599596][ T5327] CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 Not tainted 6.12.0-syzkaller-01892-g8f7c8b88bda4 #0 [ 59.603329][ T5327] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 [ 59.607125][ T5327] RIP: 0010:refcount_warn_saturate+0x15a/0x1d0 [ 59.609419][ T5327] Code: 20 de 60 8c e8 27 03 97 fc 90 0f 0b 90 90 eb 99 e8 ab ff d5 fc c6 05 67 93 48 0b 01 90 48 c7 c7 80 de 60 8c e8 07 03 97 fc 90 <0f> 0b 90 90 e9 76 ff ff ff e8 88 ff d5 fc c6 05 41 93 48 0b 01 90 [ 59.616024][ T5327] RSP: 0018:ffffc9000d28f8e8 EFLAGS: 00010246 [ 59.618209][ T5327] RAX: 556f870c1f579c00 RBX: ffff88803e966ea4 RCX: 0000000000100000 [ 59.621204][ T5327] RDX: ffffc9000e312000 RSI: 00000000000009b3 RDI: 00000000000009b4 [ 59.624460][ T5327] RBP: 0000000000000003 R08: ffffffff8155e432 R09: 1ffff11003f8519a [ 59.627703][ T5327] R10: dffffc0000000000 R11: ffffed1003f8519b R12: ffff888043720868 [ 59.630842][ T5327] R13: ffff88803e966ea4 R14: 1ffff110086e4118 R15: ffff888043720800 [ 59.633876][ T5327] FS: 00007f2909dc66c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000 [ 59.637590][ T5327] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 59.640484][ T5327] CR2: 0000000020000040 CR3: 0000000040976000 CR4: 0000000000352ef0 [ 59.643374][ T5327] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 59.645684][ T5327] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 59.648787][ T5327] Call Trace: [ 59.650240][ T5327] [ 59.651413][ T5327] ? __warn+0x168/0x4e0 [ 59.653112][ T5327] ? refcount_warn_saturate+0x15a/0x1d0 [ 59.655246][ T5327] ? report_bug+0x2b3/0x500 [ 59.656942][ T5327] ? refcount_warn_saturate+0x15a/0x1d0 [ 59.658869][ T5327] ? handle_bug+0x60/0x90 [ 59.660506][ T5327] ? exc_invalid_op+0x1a/0x50 [ 59.662150][ T5327] ? asm_exc_invalid_op+0x1a/0x20 [ 59.663907][ T5327] ? __warn_printk+0x292/0x360 [ 59.665554][ T5327] ? refcount_warn_saturate+0x15a/0x1d0 [ 59.667057][ T5327] ? refcount_warn_saturate+0x159/0x1d0 [ 59.668806][ T5327] j1939_session_put+0x1ed/0x440 [ 59.670669][ T5327] j1939_sk_sendmsg+0x121b/0x14c0 [ 59.672695][ T5327] ? __pfx_j1939_sk_sendmsg+0x10/0x10 [ 59.674761][ T5327] ? __import_iovec+0x590/0x870 [ 59.676645][ T5327] ? aa_sock_msg_perm+0x91/0x160 [ 59.678505][ T5327] ? __pfx_j1939_sk_sendmsg+0x10/0x10 [ 59.680781][ T5327] __sock_sendmsg+0x221/0x270 [ 59.682503][ T5327] ____sys_sendmsg+0x52a/0x7e0 [ 59.684193][ T5327] ? __pfx_____sys_sendmsg+0x10/0x10 [ 59.686042][ T5327] ? __fget_files+0x2a/0x410 [ 59.687725][ T5327] ? __fget_files+0x2a/0x410 [ 59.689430][ T5327] __sys_sendmsg+0x269/0x350 [ 59.690992][ T5327] ? __pfx___sys_sendmsg+0x10/0x10 [ 59.692569][ T5327] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10 [ 59.694596][ T5327] ? do_syscall_64+0x100/0x230 [ 59.696223][ T5327] ? do_syscall_64+0xb6/0x230 [ 59.697906][ T5327] do_syscall_64+0xf3/0x230 [ 59.699501][ T5327] ? clear_bhb_loop+0x35/0x90 [ 59.701052][ T5327] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 59.703163][ T5327] RIP: 0033:0x7f2908f7e819 [ 59.704796][ T5327] 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 a8 ff ff ff f7 d8 64 89 01 48 [ 59.711513][ T5327] RSP: 002b:00007f2909dc6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 59.714295][ T5327] RAX: ffffffffffffffda RBX: 00007f2909135fa0 RCX: 00007f2908f7e819 [ 59.717070][ T5327] RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000004 [ 59.719837][ T5327] RBP: 00007f2908ff175e R08: 0000000000000000 R09: 0000000000000000 [ 59.722633][ T5327] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 59.725149][ T5327] R13: 0000000000000000 R14: 00007f2909135fa0 R15: 00007ffcc73d21a8 [ 59.727860][ T5327] [ 59.729027][ T5327] Kernel panic - not syncing: kernel: panic_on_warn set ... [ 59.731736][ T5327] CPU: 0 UID: 0 PID: 5327 Comm: syz.0.0 Not tainted 6.12.0-syzkaller-01892-g8f7c8b88bda4 #0 [ 59.735588][ T5327] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 [ 59.739719][ T5327] Call Trace: [ 59.741040][ T5327] [ 59.742292][ T5327] dump_stack_lvl+0x241/0x360 [ 59.743916][ T5327] ? __pfx_dump_stack_lvl+0x10/0x10 [ 59.745600][ T5327] ? __pfx__printk+0x10/0x10 [ 59.747336][ T5327] ? vscnprintf+0x5d/0x90 [ 59.749006][ T5327] panic+0x349/0x880 [ 59.750526][ T5327] ? __warn+0x177/0x4e0 [ 59.752208][ T5327] ? __pfx_panic+0x10/0x10 [ 59.753994][ T5327] __warn+0x34b/0x4e0 [ 59.755515][ T5327] ? refcount_warn_saturate+0x15a/0x1d0 [ 59.757637][ T5327] report_bug+0x2b3/0x500 [ 59.759181][ T5327] ? refcount_warn_saturate+0x15a/0x1d0 [ 59.760954][ T5327] handle_bug+0x60/0x90 [ 59.762300][ T5327] exc_invalid_op+0x1a/0x50 [ 59.763784][ T5327] asm_exc_invalid_op+0x1a/0x20 [ 59.765450][ T5327] RIP: 0010:refcount_warn_saturate+0x15a/0x1d0 [ 59.767496][ T5327] Code: 20 de 60 8c e8 27 03 97 fc 90 0f 0b 90 90 eb 99 e8 ab ff d5 fc c6 05 67 93 48 0b 01 90 48 c7 c7 80 de 60 8c e8 07 03 97 fc 90 <0f> 0b 90 90 e9 76 ff ff ff e8 88 ff d5 fc c6 05 41 93 48 0b 01 90 [ 59.774885][ T5327] RSP: 0018:ffffc9000d28f8e8 EFLAGS: 00010246 [ 59.777103][ T5327] RAX: 556f870c1f579c00 RBX: ffff88803e966ea4 RCX: 0000000000100000 [ 59.779843][ T5327] RDX: ffffc9000e312000 RSI: 00000000000009b3 RDI: 00000000000009b4 [ 59.782723][ T5327] RBP: 0000000000000003 R08: ffffffff8155e432 R09: 1ffff11003f8519a [ 59.785681][ T5327] R10: dffffc0000000000 R11: ffffed1003f8519b R12: ffff888043720868 [ 59.789327][ T5327] R13: ffff88803e966ea4 R14: 1ffff110086e4118 R15: ffff888043720800 [ 59.792611][ T5327] ? __warn_printk+0x292/0x360 [ 59.794567][ T5327] ? refcount_warn_saturate+0x159/0x1d0 [ 59.796963][ T5327] j1939_session_put+0x1ed/0x440 [ 59.799756][ T5327] j1939_sk_sendmsg+0x121b/0x14c0 [ 59.802042][ T5327] ? __pfx_j1939_sk_sendmsg+0x10/0x10 [ 59.804519][ T5327] ? __import_iovec+0x590/0x870 [ 59.806421][ T5327] ? aa_sock_msg_perm+0x91/0x160 [ 59.808339][ T5327] ? __pfx_j1939_sk_sendmsg+0x10/0x10 [ 59.810112][ T5327] __sock_sendmsg+0x221/0x270 [ 59.811956][ T5327] ____sys_sendmsg+0x52a/0x7e0 [ 59.813844][ T5327] ? __pfx_____sys_sendmsg+0x10/0x10 [ 59.815924][ T5327] ? __fget_files+0x2a/0x410 [ 59.817690][ T5327] ? __fget_files+0x2a/0x410 [ 59.819578][ T5327] __sys_sendmsg+0x269/0x350 [ 59.821403][ T5327] ? __pfx___sys_sendmsg+0x10/0x10 [ 59.823429][ T5327] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10 [ 59.825933][ T5327] ? do_syscall_64+0x100/0x230 [ 59.827855][ T5327] ? do_syscall_64+0xb6/0x230 [ 59.829706][ T5327] do_syscall_64+0xf3/0x230 [ 59.831585][ T5327] ? clear_bhb_loop+0x35/0x90 [ 59.833382][ T5327] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 59.835473][ T5327] RIP: 0033:0x7f2908f7e819 [ 59.837268][ T5327] 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 a8 ff ff ff f7 d8 64 89 01 48 [ 59.844389][ T5327] RSP: 002b:00007f2909dc6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 59.847500][ T5327] RAX: ffffffffffffffda RBX: 00007f2909135fa0 RCX: 00007f2908f7e819 [ 59.850413][ T5327] RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000004 [ 59.853202][ T5327] RBP: 00007f2908ff175e R08: 0000000000000000 R09: 0000000000000000 [ 59.855987][ T5327] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 59.858996][ T5327] R13: 0000000000000000 R14: 00007f2909135fa0 R15: 00007ffcc73d21a8 [ 59.861933][ T5327] [ 59.863363][ T5327] Kernel Offset: disabled [ 59.865001][ T5327] Rebooting in 86400 seconds..