R10: 0000000000000000 R11: 0000000000000246 R12: 00007f26936016d4 R13: 00000000004be737 R14: 00000000004ce398 R15: 0000000000000004 binder_alloc: 15976: binder_alloc_buf, no vma binder: 15976:16034 transaction failed 29189/-3, size 0-32 line 2970 ================================================================== BUG: KASAN: use-after-free in drm_gem_object_release+0xf1/0x110 drivers/gpu/drm/drm_gem.c:813 Read of size 8 at addr ffff8801c16df1d0 by task syz-executor1/16032 CPU: 0 PID: 16032 Comm: syz-executor1 Not tainted 4.19.0+ #80 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+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 drm_gem_object_release+0xf1/0x110 drivers/gpu/drm/drm_gem.c:813 __vgem_gem_destroy drivers/gpu/drm/vgem/vgem_drv.c:175 [inline] vgem_gem_create drivers/gpu/drm/vgem/vgem_drv.c:199 [inline] vgem_gem_dumb_create+0x1f8/0x260 drivers/gpu/drm/vgem/vgem_drv.c:214 drm_mode_create_dumb+0x28d/0x310 drivers/gpu/drm/drm_dumb_buffers.c:92 drm_mode_create_dumb_ioctl+0x25/0x30 drivers/gpu/drm/drm_dumb_buffers.c:98 drm_ioctl_kernel+0x245/0x2f0 drivers/gpu/drm/drm_ioctl.c:751 drm_ioctl+0x57a/0xb20 drivers/gpu/drm/drm_ioctl.c:847 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702 __do_sys_ioctl fs/ioctl.c:709 [inline] __se_sys_ioctl fs/ioctl.c:707 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: fd b3 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 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f2693600c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f2693600c90 RCX: 0000000000457569 RDX: 0000000020000000 RSI: ffffffffffffffb2 RDI: 0000000000000003 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f26936016d4 R13: 00000000004be737 R14: 00000000004ce398 R15: 0000000000000004 Allocated by task 16032: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 kmem_cache_alloc_trace+0x152/0x750 mm/slab.c:3620 kmalloc include/linux/slab.h:513 [inline] kzalloc include/linux/slab.h:707 [inline] __vgem_gem_create+0x4c/0x100 drivers/gpu/drm/vgem/vgem_drv.c:158 vgem_gem_create drivers/gpu/drm/vgem/vgem_drv.c:187 [inline] vgem_gem_dumb_create+0xce/0x260 drivers/gpu/drm/vgem/vgem_drv.c:214 drm_mode_create_dumb+0x28d/0x310 drivers/gpu/drm/drm_dumb_buffers.c:92 drm_mode_create_dumb_ioctl+0x25/0x30 drivers/gpu/drm/drm_dumb_buffers.c:98 drm_ioctl_kernel+0x245/0x2f0 drivers/gpu/drm/drm_ioctl.c:751 drm_ioctl+0x57a/0xb20 drivers/gpu/drm/drm_ioctl.c:847 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702 __do_sys_ioctl fs/ioctl.c:709 [inline] __se_sys_ioctl fs/ioctl.c:707 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 16032: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3813 vgem_gem_free_object+0xb6/0xe0 drivers/gpu/drm/vgem/vgem_drv.c:61 drm_gem_object_free+0xf1/0x2b0 drivers/gpu/drm/drm_gem.c:839 kref_put include/linux/kref.h:70 [inline] drm_gem_object_put_unlocked+0x14c/0x180 drivers/gpu/drm/drm_gem.c:895 vgem_gem_create drivers/gpu/drm/vgem/vgem_drv.c:192 [inline] vgem_gem_dumb_create+0x120/0x260 drivers/gpu/drm/vgem/vgem_drv.c:214 drm_mode_create_dumb+0x28d/0x310 drivers/gpu/drm/drm_dumb_buffers.c:92 drm_mode_create_dumb_ioctl+0x25/0x30 drivers/gpu/drm/drm_dumb_buffers.c:98 drm_ioctl_kernel+0x245/0x2f0 drivers/gpu/drm/drm_ioctl.c:751 drm_ioctl+0x57a/0xb20 drivers/gpu/drm/drm_ioctl.c:847 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702 __do_sys_ioctl fs/ioctl.c:709 [inline] __se_sys_ioctl fs/ioctl.c:707 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8801c16df0c0 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 272 bytes inside of 512-byte region [ffff8801c16df0c0, ffff8801c16df2c0) The buggy address belongs to the page: page:ffffea000705b7c0 count:1 mapcount:0 mapping:ffff8801da800940 index:0xffff8801c16df840 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea0007066e48 ffffea000714f1c8 ffff8801da800940 raw: ffff8801c16df840 ffff8801c16df0c0 0000000100000004 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c16df080: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ffff8801c16df100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801c16df180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801c16df200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c16df280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================