vcan0: j1939_tp_rxtimer: 0x00000000e60fd448: rx timeout, send abort
vcan0: j1939_tp_rxtimer: 0x00000000e60fd448: abort rx timeout. Force session deactivation
==================================================================
BUG: KASAN: use-after-free in __run_hrtimer kernel/time/hrtimer.c:1521 [inline]
BUG: KASAN: use-after-free in __hrtimer_run_queues+0xe18/0xf10 kernel/time/hrtimer.c:1583
Read of size 1 at addr ffff8880a47d1973 by task syz-fuzzer/7052

CPU: 1 PID: 7052 Comm: syz-fuzzer Not tainted 5.6.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd3/0x315 mm/kasan/report.c:374
 __kasan_report.cold+0x1a/0x32 mm/kasan/report.c:506
 kasan_report+0xe/0x20 mm/kasan/common.c:641
 __run_hrtimer kernel/time/hrtimer.c:1521 [inline]
 __hrtimer_run_queues+0xe18/0xf10 kernel/time/hrtimer.c:1583
 hrtimer_run_softirq+0x16d/0x250 kernel/time/hrtimer.c:1600
 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x192/0x1d0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:546 [inline]
 smp_apic_timer_interrupt+0x19e/0x600 arch/x86/kernel/apic/apic.c:1140
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0033:0x7782fa
Code: 48 85 c0 e9 ea fd ff ff 48 89 94 24 a8 00 00 00 48 8d 05 99 50 18 00 48 89 04 24 e8 10 46 c9 ff 48 8b 84 24 a8 00 00 00 84 00 <48> 8b 4c 24 08 48 89 4c 24 60 83 3d f5 2a 96 01 00 0f 85 69 01 00
RSP: 002b:000000c00021e608 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 000000c0004f7180 RBX: 0000000000000000 RCX: 000000c000001c80
RDX: 0000000000000001 RSI: 0000000000000038 RDI: 0000000000000038
RBP: 000000c00021e6f0 R08: 00007fd7b592fe45 R09: 0000000000203002
R10: 0000000000000008 R11: 0000000000000074 R12: 00000000000000f4
R13: 0000000000000000 R14: 0000000000ac9915 R15: 0000000000000000

Allocated by task 27273:
 save_stack+0x1b/0x80 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 __kasan_kmalloc mm/kasan/common.c:515 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:488
 kmem_cache_alloc_trace+0x153/0x7d0 mm/slab.c:3551
 kmalloc include/linux/slab.h:555 [inline]
 kzalloc include/linux/slab.h:669 [inline]
 j1939_session_new+0x7c/0x3f0 net/can/j1939/transport.c:1418
 j1939_tp_send+0x22f/0x800 net/can/j1939/transport.c:1877
 j1939_sk_send_loop net/can/j1939/socket.c:1037 [inline]
 j1939_sk_sendmsg+0xabf/0x1360 net/can/j1939/socket.c:1160
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 ____sys_sendmsg+0x6bf/0x7e0 net/socket.c:2362
 ___sys_sendmsg+0x100/0x170 net/socket.c:2416
 __sys_sendmsg+0xec/0x1b0 net/socket.c:2449
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

Freed by task 7052:
 save_stack+0x1b/0x80 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 kasan_set_free_info mm/kasan/common.c:337 [inline]
 __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:476
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x109/0x2b0 mm/slab.c:3757
 j1939_session_destroy net/can/j1939/transport.c:276 [inline]
 __j1939_session_release net/can/j1939/transport.c:284 [inline]
 kref_put include/linux/kref.h:65 [inline]
 j1939_session_put+0x25c/0x330 net/can/j1939/transport.c:289
 j1939_tp_rxtimer+0x2e9/0x2f4 net/can/j1939/transport.c:1194
 __run_hrtimer kernel/time/hrtimer.c:1519 [inline]
 __hrtimer_run_queues+0x3a2/0xf10 kernel/time/hrtimer.c:1583
 hrtimer_run_softirq+0x16d/0x250 kernel/time/hrtimer.c:1600
 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292

The buggy address belongs to the object at ffff8880a47d1800
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 371 bytes inside of
 512-byte region [ffff8880a47d1800, ffff8880a47d1a00)
The buggy address belongs to the page:
page:ffffea000291f440 refcount:1 mapcount:0 mapping:ffff8880aa000a80 index:0xffff8880a47d1400
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea0001903fc8 ffffea00025cfbc8 ffff8880aa000a80
raw: ffff8880a47d1400 ffff8880a47d1000 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a47d1800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880a47d1880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880a47d1900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff8880a47d1980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880a47d1a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================