netlink: 12 bytes leftover after parsing attributes in process `syz-executor.1'. ================================================================== BUG: KASAN: use-after-free in v4l2_m2m_try_schedule drivers/media/v4l2-core/v4l2-mem2mem.c:361 [inline] BUG: KASAN: use-after-free in v4l2_m2m_job_finish+0x33f/0x350 drivers/media/v4l2-core/v4l2-mem2mem.c:427 Read of size 8 at addr ffff88809b20e4c8 by task kworker/1:0/19 CPU: 1 PID: 19 Comm: kworker/1:0 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Workqueue: events device_work 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 mm/kasan/report.c:412 [inline] __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433 v4l2_m2m_try_schedule drivers/media/v4l2-core/v4l2-mem2mem.c:361 [inline] v4l2_m2m_job_finish+0x33f/0x350 drivers/media/v4l2-core/v4l2-mem2mem.c:427 device_work+0x28b/0x350 drivers/media/platform/vim2m.c:417 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Allocated by task 13245: kmem_cache_alloc_trace+0x12f/0x380 mm/slab.c:3625 kmalloc include/linux/slab.h:515 [inline] kzalloc include/linux/slab.h:709 [inline] v4l2_m2m_ctx_init+0x49/0x380 drivers/media/v4l2-core/v4l2-mem2mem.c:885 vim2m_open+0x445/0x620 drivers/media/platform/vim2m.c:928 v4l2_open+0x1af/0x350 drivers/media/v4l2-core/v4l2-dev.c:427 chrdev_open+0x266/0x770 fs/char_dev.c:423 do_dentry_open+0x4aa/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x793/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 13245: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 vim2m_release+0xe0/0x140 drivers/media/platform/vim2m.c:961 v4l2_release+0xf4/0x190 drivers/media/v4l2-core/v4l2-dev.c:448 __fput+0x2ce/0x890 fs/file_table.c:278 task_work_run+0x148/0x1c0 kernel/task_work.c:113 get_signal+0x1b64/0x1f70 kernel/signal.c:2400 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 ffff88809b20e4c0 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 8 bytes inside of 2048-byte region [ffff88809b20e4c0, ffff88809b20ecc0) The buggy address belongs to the page: page:ffffea00026c8380 count:1 mapcount:0 mapping:ffff88813bff0c40 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea00027f8988 ffffea00027b8508 ffff88813bff0c40 raw: 0000000000000000 ffff88809b20e4c0 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809b20e380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809b20e400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88809b20e480: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff88809b20e500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809b20e580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================