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BUG: KASAN: use-after-free in memcpy include/linux/string.h:380 [inline]
BUG: KASAN: use-after-free in j1939_session_tx_dat net/can/j1939/transport.c:790 [inline]
BUG: KASAN: use-after-free in j1939_xtp_txnext_transmiter net/can/j1939/transport.c:847 [inline]
BUG: KASAN: use-after-free in j1939_tp_txtimer+0x777/0x1b00 net/can/j1939/transport.c:1095
Read of size 7 at addr ffff8880857fffff by task ksoftirqd/1/16

CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.5.0-rc3-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+0x197/0x210 lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:639
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192
 memcpy+0x24/0x50 mm/kasan/common.c:125
 memcpy include/linux/string.h:380 [inline]
 j1939_session_tx_dat net/can/j1939/transport.c:790 [inline]
 j1939_xtp_txnext_transmiter net/can/j1939/transport.c:847 [inline]
 j1939_tp_txtimer+0x777/0x1b00 net/can/j1939/transport.c:1095
 __run_hrtimer kernel/time/hrtimer.c:1517 [inline]
 __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1579
 hrtimer_run_softirq+0x17e/0x270 kernel/time/hrtimer.c:1596
 __do_softirq+0x262/0x98c kernel/softirq.c:292
 run_ksoftirqd kernel/softirq.c:603 [inline]
 run_ksoftirqd+0x8e/0x110 kernel/softirq.c:595
 smpboot_thread_fn+0x6a3/0xa40 kernel/smpboot.c:165
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

The buggy address belongs to the page:
page:ffffea000215ffc0 refcount:1 mapcount:1 mapping:ffff888087c340f1 index:0xc436257
anon flags: 0xfffe0000080034(uptodate|lru|active|swapbacked)
raw: 00fffe0000080034 ffffea000215ff88 ffffea0002303608 ffff888087c340f1
raw: 000000000c436257 0000000000000000 0000000100000000 ffff88821b7b4000
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff88821b7b4000

Memory state around the buggy address:
 ffff8880857fff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880857fff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888085800000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff888085800080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888085800100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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