vcan0: j1939_tp_rxtimer: 0x000000005200c3b0: 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 ffff88809e35ad73 by task ksoftirqd/1/16 CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.6.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __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+0x35/0x4d mm/kasan/report.c:503 kasan_report+0x33/0x50 mm/kasan/common.c:648 __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 run_ksoftirqd kernel/softirq.c:604 [inline] run_ksoftirqd+0x89/0x100 kernel/softirq.c:596 smpboot_thread_fn+0x653/0x9e0 kernel/smpboot.c:165 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 6400: save_stack+0x1b/0x80 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:518 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:491 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 sock_no_sendpage+0xf8/0x140 net/core/sock.c:2763 kernel_sendpage+0x82/0xd0 net/socket.c:3808 sock_sendpage+0x8a/0xb0 net/socket.c:950 pipe_to_sendpage+0x2aa/0x380 fs/splice.c:458 splice_from_pipe_feed fs/splice.c:512 [inline] __splice_from_pipe+0x3e6/0x7b0 fs/splice.c:636 splice_from_pipe+0xd9/0x140 fs/splice.c:671 do_splice_from fs/splice.c:863 [inline] direct_splice_actor+0x115/0x160 fs/splice.c:1037 splice_direct_to_actor+0x38c/0x980 fs/splice.c:992 do_splice_direct+0x1b4/0x280 fs/splice.c:1080 do_sendfile+0x555/0xc50 fs/read_write.c:1520 __do_sys_sendfile64 fs/read_write.c:1581 [inline] __se_sys_sendfile64 fs/read_write.c:1567 [inline] __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1567 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Freed by task 16: 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:340 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:479 __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 ffff88809e35ac00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 371 bytes inside of 512-byte region [ffff88809e35ac00, ffff88809e35ae00) The buggy address belongs to the page: page:ffffea000278d680 refcount:1 mapcount:0 mapping:00000000d260dbcc index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea00026849c8 ffffea000188ee08 ffff8880aa000a80 raw: 0000000000000000 ffff88809e35a000 0000000100000004 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809e35ac00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809e35ac80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88809e35ad00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88809e35ad80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809e35ae00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================