================================================================== BUG: KASAN: use-after-free in memcpy include/linux/string.h:377 [inline] BUG: KASAN: use-after-free in skb_put_data include/linux/skbuff.h:2130 [inline] BUG: KASAN: use-after-free in bcm_can_tx+0x3d4/0x800 net/can/bcm.c:295 Read of size 72 at addr ffff8880963fbf98 by task ksoftirqd/0/9 CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/21/2023 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report+0x8f/0xa0 mm/kasan/report.c:412 memcpy+0x20/0x50 mm/kasan/kasan.c:302 memcpy include/linux/string.h:377 [inline] skb_put_data include/linux/skbuff.h:2130 [inline] bcm_can_tx+0x3d4/0x800 net/can/bcm.c:295 bcm_tx_timeout_tsklet+0x1f0/0x3a0 net/can/bcm.c:414 tasklet_action_common.constprop.0+0x265/0x360 kernel/softirq.c:522 __do_softirq+0x265/0x980 kernel/softirq.c:292 run_ksoftirqd+0x57/0x110 kernel/softirq.c:653 smpboot_thread_fn+0x655/0x9e0 kernel/smpboot.c:164 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Allocated by task 26576: __do_kmalloc mm/slab.c:3727 [inline] __kmalloc+0x15a/0x3c0 mm/slab.c:3736 kmalloc_array include/linux/slab.h:637 [inline] bcm_tx_setup net/can/bcm.c:957 [inline] bcm_sendmsg+0x316c/0x4150 net/can/bcm.c:1386 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:661 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2227 __sys_sendmsg net/socket.c:2265 [inline] __do_sys_sendmsg net/socket.c:2274 [inline] __se_sys_sendmsg net/socket.c:2272 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2272 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 26576: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 bcm_remove_op+0x213/0x2c0 net/can/bcm.c:770 bcm_release+0x260/0x950 net/can/bcm.c:1561 __sock_release+0xcd/0x2a0 net/socket.c:599 sock_close+0x15/0x20 net/socket.c:1214 __fput+0x2ce/0x890 fs/file_table.c:278 task_work_run+0x148/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xbf3/0x2be0 kernel/exit.c:870 do_group_exit+0x125/0x310 kernel/exit.c:967 get_signal+0x3f2/0x1f70 kernel/signal.c:2589 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:799 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880963f9640 which belongs to the cache kmalloc-16384 of size 16384 The buggy address is located 10584 bytes inside of 16384-byte region [ffff8880963f9640, ffff8880963fd640) The buggy address belongs to the page: page:ffffea000258fe00 count:1 mapcount:0 mapping:ffff88813bff2200 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea0001b7fe08 ffff88813bff1c48 ffff88813bff2200 raw: 0000000000000000 ffff8880963f9640 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880963fbe80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880963fbf00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880963fbf80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880963fc000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880963fc080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================