------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 0 PID: 17157 at lib/refcount.c:25 refcount_warn_saturate+0x108/0x1a0 lib/refcount.c:25
Modules linked in:
CPU: 0 PID: 17157 Comm: syz-executor.1 Not tainted 5.12.0-rc5-syzkaller-00003-g1e43c377a79f #0
Hardware name: linux,dummy-virt (DT)
pstate: 60000005 (nZCv daif -PAN -UAO -TCO BTYPE=--)
pc : refcount_warn_saturate+0x108/0x1a0 lib/refcount.c:25
lr : refcount_warn_saturate+0x108/0x1a0 lib/refcount.c:25
sp : ffff00002dcdfb70
x29: ffff00002dcdfb70 x28: ffff80001712f2c0 
x27: ffff00000ab94000 x26: ffff00000fe50568 
x25: 1fffe00001fca0ad x24: 1fffe000015c400a 
x23: ffff00000ab94000 x22: ffff800014fa79c0 
x21: ffff0000089b3480 x20: ffff00000ab95108 
x19: 0000000000000002 x18: ffff00006ab14b48 
x17: 0000000000000000 x16: 0000000000000007 
x15: ffff8000172c8810 x14: 1fffe00005b9bea4 
x13: 0000000000000001 x12: ffff60000d562984 
x11: 1fffe0000d562983 x10: ffff60000d562983 
x9 : dfff800000000000 x8 : ffff00006ab14c1b 
x7 : 0000000000000001 x6 : 00009ffff2a9d67d 
x5 : ffff00006ab14c18 x4 : 1fffe00001136691 
x3 : dfff800000000000 x2 : 0000000000000000 
x1 : 0000000000000000 x0 : ffff0000089b3480 
Call trace:
 refcount_warn_saturate+0x108/0x1a0 lib/refcount.c:25
 __refcount_add include/linux/refcount.h:199 [inline]
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 kref_get include/linux/kref.h:45 [inline]
 j1939_netdev_start+0x7bc/0x900 net/can/j1939/main.c:271
 j1939_sk_bind+0x2c8/0xd30 net/can/j1939/socket.c:479
 __sys_bind+0x16c/0x1d0 net/socket.c:1637
 __do_sys_bind net/socket.c:1648 [inline]
 __se_sys_bind net/socket.c:1646 [inline]
 __arm64_sys_bind+0x6c/0xa0 net/socket.c:1646
 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
 invoke_syscall arch/arm64/kernel/syscall.c:49 [inline]
 el0_svc_common.constprop.0+0xf0/0x2c0 arch/arm64/kernel/syscall.c:129
 do_el0_svc_compat+0x40/0x70 arch/arm64/kernel/syscall.c:174
 el0_svc_compat+0x24/0x3c arch/arm64/kernel/entry-common.c:494
 el0_sync_compat_handler+0x90/0x140 arch/arm64/kernel/entry-common.c:503
 el0_sync_compat+0x174/0x180 arch/arm64/kernel/entry.S:708
irq event stamp: 3998
hardirqs last  enabled at (3997): [<ffff8000102a9790>] console_unlock+0x81c/0xc1c kernel/printk/printk.c:2605
hardirqs last disabled at (3998): [<ffff8000143e72a4>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:237
softirqs last  enabled at (3974): [<ffff8000100109e0>] _stext+0x9e0/0x1084
softirqs last disabled at (3947): [<ffff80001015a03c>] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline]
softirqs last disabled at (3947): [<ffff80001015a03c>] invoke_softirq kernel/softirq.c:228 [inline]
softirqs last disabled at (3947): [<ffff80001015a03c>] __irq_exit_rcu+0x46c/0x510 kernel/softirq.c:422
---[ end trace 4783d8a03d6436c7 ]---