================================================================== BUG: KASAN: use-after-free in __vb2_perform_fileio+0x1065/0x1140 drivers/media/common/videobuf2/videobuf2-core.c:2613 Read of size 4 at addr ffff888060e239dc by task syz-executor.0/4571 CPU: 1 PID: 4571 Comm: syz-executor.0 Not tainted 5.1.0-rc5+ #71 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+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131 __vb2_perform_fileio+0x1065/0x1140 drivers/media/common/videobuf2/videobuf2-core.c:2613 vb2_read+0x3b/0x50 drivers/media/common/videobuf2/videobuf2-core.c:2724 vb2_fop_read+0x212/0x410 drivers/media/common/videobuf2/videobuf2-v4l2.c:1090 v4l2_read+0x1ce/0x230 drivers/media/v4l2-core/v4l2-dev.c:317 __vfs_read+0x8d/0x110 fs/read_write.c:416 vfs_read+0x194/0x3e0 fs/read_write.c:452 ksys_read+0x14f/0x2d0 fs/read_write.c:579 __do_sys_read fs/read_write.c:589 [inline] __se_sys_read fs/read_write.c:587 [inline] __x64_sys_read+0x73/0xb0 fs/read_write.c:587 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458c29 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fe19925dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458c29 RDX: 000000000000004b RSI: 0000000020000280 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe19925e6d4 R13: 00000000004c4935 R14: 00000000004d9f08 R15: 00000000ffffffff Allocated by task 4571: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc mm/kasan/common.c:497 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:511 kmem_cache_alloc_trace+0x151/0x760 mm/slab.c:3623 kmalloc include/linux/slab.h:547 [inline] kzalloc include/linux/slab.h:742 [inline] __vb2_init_fileio+0x1cb/0xbe0 drivers/media/common/videobuf2/videobuf2-core.c:2458 __vb2_perform_fileio+0xc01/0x1140 drivers/media/common/videobuf2/videobuf2-core.c:2592 vb2_read+0x3b/0x50 drivers/media/common/videobuf2/videobuf2-core.c:2724 vb2_fop_read+0x212/0x410 drivers/media/common/videobuf2/videobuf2-v4l2.c:1090 v4l2_read+0x1ce/0x230 drivers/media/v4l2-core/v4l2-dev.c:317 __vfs_read+0x8d/0x110 fs/read_write.c:416 vfs_read+0x194/0x3e0 fs/read_write.c:452 ksys_read+0x14f/0x2d0 fs/read_write.c:579 __do_sys_read fs/read_write.c:589 [inline] __se_sys_read fs/read_write.c:587 [inline] __x64_sys_read+0x73/0xb0 fs/read_write.c:587 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 4572: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467 __cache_free mm/slab.c:3500 [inline] kfree+0xcf/0x230 mm/slab.c:3823 __vb2_cleanup_fileio+0x100/0x170 drivers/media/common/videobuf2/videobuf2-core.c:2551 vb2_core_queue_release+0x20/0x80 drivers/media/common/videobuf2/videobuf2-core.c:2274 vb2_queue_release drivers/media/common/videobuf2/videobuf2-v4l2.c:864 [inline] _vb2_fop_release+0x1cf/0x2a0 drivers/media/common/videobuf2/videobuf2-v4l2.c:1035 vb2_fop_release+0x75/0xc0 drivers/media/common/videobuf2/videobuf2-v4l2.c:1049 vivid_fop_release+0x18e/0x430 drivers/media/platform/vivid/vivid-core.c:475 v4l2_release+0x224/0x3a0 drivers/media/v4l2-core/v4l2-dev.c:456 __fput+0x2e5/0x8d0 fs/file_table.c:278 ____fput+0x16/0x20 fs/file_table.c:309 task_work_run+0x14a/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x273/0x2c0 arch/x86/entry/common.c:166 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline] syscall_return_slowpath arch/x86/entry/common.c:268 [inline] do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888060e236c0 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 796 bytes inside of 1024-byte region [ffff888060e236c0, ffff888060e23ac0) The buggy address belongs to the page: page:ffffea0001838880 count:1 mapcount:0 mapping:ffff88812c3f0ac0 index:0xffff888060e22040 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea00022d7808 ffffea0002532b88 ffff88812c3f0ac0 raw: ffff888060e22040 ffff888060e22040 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888060e23880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888060e23900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888060e23980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888060e23a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888060e23a80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================