program: r0 = socket$can_j1939(0x1d, 0x2, 0x7) r1 = socket$nl_generic(0x10, 0x3, 0x10) ioctl$ifreq_SIOCGIFINDEX_vcan(r1, 0x8933, &(0x7f0000000140)={'vcan0\x00', 0x0}) bind$can_j1939(r0, &(0x7f0000000300)={0x1d, r2}, 0x18) sendmsg$can_j1939(r0, &(0x7f0000000180)={&(0x7f0000000040)={0x1d, 0x0, 0x0, {0x0, 0x1}}, 0x18, &(0x7f0000000100)={&(0x7f00000000c0)="d4", 0x1}}, 0x0) [ 73.347482][ T5310] Bluetooth: hci0: command tx timeout [ 73.448753][ T5325] ------------[ cut here ]------------ [ 73.450885][ T5325] refcount_t: underflow; use-after-free. [ 73.453288][ T5325] WARNING: CPU: 0 PID: 5325 at lib/refcount.c:28 refcount_warn_saturate+0x15a/0x1d0 [ 73.457216][ T5325] Modules linked in: [ 73.458655][ T5325] CPU: 0 UID: 0 PID: 5325 Comm: syz.0.0 Not tainted 6.13.0-rc1-syzkaller-00025-gfeffde684ac2 #0 [ 73.462310][ T5325] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 [ 73.466814][ T5325] RIP: 0010:refcount_warn_saturate+0x15a/0x1d0 [ 73.469346][ T5325] Code: e0 1e 5f 8c e8 87 c5 95 fc 90 0f 0b 90 90 eb 99 e8 2b 1e d5 fc c6 05 6d 2c 39 0b 01 90 48 c7 c7 40 1f 5f 8c e8 67 c5 95 fc 90 <0f> 0b 90 90 e9 76 ff ff ff e8 08 1e d5 fc c6 05 47 2c 39 0b 01 90 [ 73.476836][ T5325] RSP: 0018:ffffc9000d3378e8 EFLAGS: 00010246 [ 73.479096][ T5325] RAX: 501f4696829f7a00 RBX: ffff888040333224 RCX: 0000000000100000 [ 73.482148][ T5325] RDX: ffffc9000ebb1000 RSI: 00000000000009be RDI: 00000000000009bf [ 73.485313][ T5325] RBP: 0000000000000003 R08: ffffffff81601c02 R09: 1ffff11003f8519a [ 73.488702][ T5325] R10: dffffc0000000000 R11: ffffed1003f8519b R12: ffff888040e1c868 [ 73.491335][ T5325] R13: ffff888040333224 R14: 1ffff110081c3918 R15: ffff888040e1c800 [ 73.494421][ T5325] FS: 00007f28dde306c0(0000) GS:ffff88801fc00000(0000) knlGS:0000000000000000 [ 73.498140][ T5325] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 73.500774][ T5325] CR2: 0000000020000140 CR3: 0000000042826000 CR4: 0000000000352ef0 [ 73.504251][ T5325] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 73.507772][ T5325] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 73.510863][ T5325] Call Trace: [ 73.512179][ T5325] [ 73.513416][ T5325] ? __warn+0x165/0x4d0 [ 73.515167][ T5325] ? refcount_warn_saturate+0x15a/0x1d0 [ 73.517754][ T5325] ? report_bug+0x2b3/0x500 [ 73.519672][ T5325] ? refcount_warn_saturate+0x15a/0x1d0 [ 73.521831][ T5325] ? handle_bug+0x60/0x90 [ 73.523693][ T5325] ? exc_invalid_op+0x1a/0x50 [ 73.525590][ T5325] ? asm_exc_invalid_op+0x1a/0x20 [ 73.528047][ T5325] ? __warn_printk+0x292/0x360 [ 73.530037][ T5325] ? refcount_warn_saturate+0x15a/0x1d0 [ 73.532196][ T5325] ? refcount_warn_saturate+0x159/0x1d0 [ 73.534886][ T5325] j1939_session_put+0x1ed/0x440 [ 73.537385][ T5325] j1939_sk_sendmsg+0x121b/0x14c0 [ 73.539323][ T5325] ? __pfx_j1939_sk_sendmsg+0x10/0x10 [ 73.541387][ T5325] ? __import_iovec+0x590/0x870 [ 73.543215][ T5325] ? aa_sock_msg_perm+0x91/0x160 [ 73.545154][ T5325] ? __pfx_j1939_sk_sendmsg+0x10/0x10 [ 73.547609][ T5325] __sock_sendmsg+0x221/0x270 [ 73.549411][ T5325] ____sys_sendmsg+0x52a/0x7e0 [ 73.551202][ T5325] ? __pfx_____sys_sendmsg+0x10/0x10 [ 73.553088][ T5325] ? __fget_files+0x2a/0x410 [ 73.554826][ T5325] ? __fget_files+0x2a/0x410 [ 73.557006][ T5325] __sys_sendmsg+0x269/0x350 [ 73.558914][ T5325] ? __pfx___sys_sendmsg+0x10/0x10 [ 73.560853][ T5325] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10 [ 73.563175][ T5325] ? do_syscall_64+0x100/0x230 [ 73.565112][ T5325] ? do_syscall_64+0xb6/0x230 [ 73.567296][ T5325] do_syscall_64+0xf3/0x230 [ 73.568977][ T5325] ? clear_bhb_loop+0x35/0x90 [ 73.570674][ T5325] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 73.572980][ T5325] RIP: 0033:0x7f28dcf7ff19 [ 73.574687][ T5325] 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 [ 73.582225][ T5325] RSP: 002b:00007f28dde30058 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 73.585644][ T5325] RAX: ffffffffffffffda RBX: 00007f28dd145fa0 RCX: 00007f28dcf7ff19 [ 73.589091][ T5325] RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000003 [ 73.592166][ T5325] RBP: 00007f28dcff3986 R08: 0000000000000000 R09: 0000000000000000 [ 73.595325][ T5325] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 73.598940][ T5325] R13: 0000000000000000 R14: 00007f28dd145fa0 R15: 00007fff2ccd6248 [ 73.602028][ T5325] [ 73.603256][ T5325] Kernel panic - not syncing: kernel: panic_on_warn set ... [ 73.605911][ T5325] CPU: 0 UID: 0 PID: 5325 Comm: syz.0.0 Not tainted 6.13.0-rc1-syzkaller-00025-gfeffde684ac2 #0 [ 73.609756][ T5325] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 [ 73.613624][ T5325] Call Trace: [ 73.614745][ T5325] [ 73.615822][ T5325] dump_stack_lvl+0x241/0x360 [ 73.617611][ T5325] ? __pfx_dump_stack_lvl+0x10/0x10 [ 73.619613][ T5325] ? __pfx__printk+0x10/0x10 [ 73.621447][ T5325] ? _printk+0xd5/0x120 [ 73.623179][ T5325] ? __init_begin+0x41000/0x41000 [ 73.625157][ T5325] ? vscnprintf+0x5d/0x90 [ 73.626870][ T5325] panic+0x349/0x880 [ 73.628433][ T5325] ? __warn+0x174/0x4d0 [ 73.629999][ T5325] ? __pfx_panic+0x10/0x10 [ 73.631692][ T5325] __warn+0x344/0x4d0 [ 73.633190][ T5325] ? refcount_warn_saturate+0x15a/0x1d0 [ 73.635236][ T5325] report_bug+0x2b3/0x500 [ 73.636916][ T5325] ? refcount_warn_saturate+0x15a/0x1d0 [ 73.638983][ T5325] handle_bug+0x60/0x90 [ 73.640446][ T5325] exc_invalid_op+0x1a/0x50 [ 73.642075][ T5325] asm_exc_invalid_op+0x1a/0x20 [ 73.643896][ T5325] RIP: 0010:refcount_warn_saturate+0x15a/0x1d0 [ 73.646251][ T5325] Code: e0 1e 5f 8c e8 87 c5 95 fc 90 0f 0b 90 90 eb 99 e8 2b 1e d5 fc c6 05 6d 2c 39 0b 01 90 48 c7 c7 40 1f 5f 8c e8 67 c5 95 fc 90 <0f> 0b 90 90 e9 76 ff ff ff e8 08 1e d5 fc c6 05 47 2c 39 0b 01 90 [ 73.653479][ T5325] RSP: 0018:ffffc9000d3378e8 EFLAGS: 00010246 [ 73.655753][ T5325] RAX: 501f4696829f7a00 RBX: ffff888040333224 RCX: 0000000000100000 [ 73.658779][ T5325] RDX: ffffc9000ebb1000 RSI: 00000000000009be RDI: 00000000000009bf [ 73.661860][ T5325] RBP: 0000000000000003 R08: ffffffff81601c02 R09: 1ffff11003f8519a [ 73.664849][ T5325] R10: dffffc0000000000 R11: ffffed1003f8519b R12: ffff888040e1c868 [ 73.667657][ T5325] R13: ffff888040333224 R14: 1ffff110081c3918 R15: ffff888040e1c800 [ 73.670448][ T5325] ? __warn_printk+0x292/0x360 [ 73.672329][ T5325] ? refcount_warn_saturate+0x159/0x1d0 [ 73.674405][ T5325] j1939_session_put+0x1ed/0x440 [ 73.676222][ T5325] j1939_sk_sendmsg+0x121b/0x14c0 [ 73.678241][ T5325] ? __pfx_j1939_sk_sendmsg+0x10/0x10 [ 73.680351][ T5325] ? __import_iovec+0x590/0x870 [ 73.682338][ T5325] ? aa_sock_msg_perm+0x91/0x160 [ 73.684200][ T5325] ? __pfx_j1939_sk_sendmsg+0x10/0x10 [ 73.686146][ T5325] __sock_sendmsg+0x221/0x270 [ 73.687952][ T5325] ____sys_sendmsg+0x52a/0x7e0 [ 73.689695][ T5325] ? __pfx_____sys_sendmsg+0x10/0x10 [ 73.691633][ T5325] ? __fget_files+0x2a/0x410 [ 73.693329][ T5325] ? __fget_files+0x2a/0x410 [ 73.695035][ T5325] __sys_sendmsg+0x269/0x350 [ 73.696694][ T5325] ? __pfx___sys_sendmsg+0x10/0x10 [ 73.698715][ T5325] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10 [ 73.701213][ T5325] ? do_syscall_64+0x100/0x230 [ 73.702725][ T5325] ? do_syscall_64+0xb6/0x230 [ 73.704248][ T5325] do_syscall_64+0xf3/0x230 [ 73.705776][ T5325] ? clear_bhb_loop+0x35/0x90 [ 73.707542][ T5325] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 73.709644][ T5325] RIP: 0033:0x7f28dcf7ff19 [ 73.711307][ T5325] 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 [ 73.718228][ T5325] RSP: 002b:00007f28dde30058 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 73.721424][ T5325] RAX: ffffffffffffffda RBX: 00007f28dd145fa0 RCX: 00007f28dcf7ff19 [ 73.724382][ T5325] RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000003 [ 73.727215][ T5325] RBP: 00007f28dcff3986 R08: 0000000000000000 R09: 0000000000000000 [ 73.730130][ T5325] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 73.733132][ T5325] R13: 0000000000000000 R14: 00007f28dd145fa0 R15: 00007fff2ccd6248 [ 73.736084][ T5325] [ 73.737449][ T5325] Kernel Offset: disabled [ 73.739020][ T5325] Rebooting in 86400 seconds..