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 ================================================================== 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 ffff8801d83d3410 by task syz-executor977/6742 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: 0033:0x445989 Code: e8 4c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 6b c8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffcf076f4e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffcf076f500 RCX: 0000000000445989 RDX: 0000000020000000 RSI: ffffffffffffffb2 RDI: 0000000000000003 RBP: 0000000000000004 R08: 0000000000000001 R09: 0000000000000100 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: ffffffffffffffff R14: 0000000000000000 R15: 0000000000000000 CPU: 0 PID: 6742 Comm: syz-executor977 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: 0033:0x445989 Code: e8 4c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 6b c8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffcf076f4e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffcf076f500 RCX: 0000000000445989 RDX: 0000000020000000 RSI: ffffffffffffffb2 RDI: 0000000000000003 RBP: 0000000000000004 R08: 0000000000000001 R09: 0000000000000100 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: ffffffffffffffff R14: 0000000000000000 R15: 0000000000000000 Allocated by task 6742: 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 6742: 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 ffff8801d83d3300 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 272 bytes inside of 512-byte region [ffff8801d83d3300, ffff8801d83d3500) The buggy address belongs to the page: page:ffffea000760f4c0 count:1 mapcount:0 mapping:ffff8801da800940 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea0007473948 ffffea0007471dc8 ffff8801da800940 raw: 0000000000000000 ffff8801d83d3080 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d83d3300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d83d3380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801d83d3400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801d83d3480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d83d3500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ================================================================== CPU: 0 PID: 6778 Comm: syz-executor977 Tainted: G B 4.19.0+ #80 BUG: KASAN: double-free or invalid-free in __vgem_gem_destroy drivers/gpu/drm/vgem/vgem_drv.c:176 [inline] BUG: KASAN: double-free or invalid-free in vgem_gem_create drivers/gpu/drm/vgem/vgem_drv.c:199 [inline] BUG: KASAN: double-free or invalid-free in vgem_gem_dumb_create+0x203/0x260 drivers/gpu/drm/vgem/vgem_drv.c:214 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 fail_dump lib/fault-inject.c:51 [inline] should_fail.cold.4+0xa/0x17 lib/fault-inject.c:149 __should_failslab+0x124/0x180 mm/failslab.c:32 should_failslab+0x9/0x14 mm/slab_common.c:1557 slab_pre_alloc_hook mm/slab.h:423 [inline] slab_alloc mm/slab.c:3378 [inline] kmem_cache_alloc_trace+0x2d7/0x750 mm/slab.c:3618 kmalloc include/linux/slab.h:513 [inline] drm_vma_node_allow+0x5f/0x290 drivers/gpu/drm/drm_vma_manager.c:277 drm_gem_handle_create_tail+0x233/0x440 drivers/gpu/drm/drm_gem.c:409 drm_gem_handle_create+0x52/0x60 drivers/gpu/drm/drm_gem.c:452 vgem_gem_create drivers/gpu/drm/vgem/vgem_drv.c:191 [inline] vgem_gem_dumb_create+0x115/0x260 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: 0033:0x445989 Code: e8 4c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 6b c8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffcf076f4e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffcf076f500 RCX: 0000000000445989 RDX: 0000000020000000 RSI: ffffffffffffffb2 RDI: 0000000000000003 RBP: 0000000000000004 R08: 0000000000000001 R09: 0000000000000100 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: ffffffffffffffff R14: 0000000000000000 R15: 0000000000000000 CPU: 1 PID: 6767 Comm: syz-executor977 Tainted: G B 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_invalid_free+0x64/0xa0 mm/kasan/report.c:336 __kasan_slab_free+0x13a/0x150 mm/kasan/kasan.c:501 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_destroy drivers/gpu/drm/vgem/vgem_drv.c:176 [inline] vgem_gem_create drivers/gpu/drm/vgem/vgem_drv.c:199 [inline] vgem_gem_dumb_create+0x203/0x260 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: 0033:0x445989 Code: e8 4c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 6b c8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffcf076f4e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ffcf076f500 RCX: 0000000000445989 RDX: 0000000020000000 RSI: ffffffffffffffb2 RDI: 0000000000000003 RBP: 0000000000000004 R08: 0000000000000001 R09: 0000000000000100 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: ffffffffffffffff R14: 0000000000000000 R15: 0000000000000000 Allocated by task 6767: 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 6767: 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 ffff8801d4974080 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 0 bytes inside of 512-byte region [ffff8801d4974080, ffff8801d4974280) The buggy address belongs to the page: page:ffffea0007525d00 count:1 mapcount:0 mapping:ffff8801da800940 index:0x0 flags: 0x2fffc0000000100(slab) raw: 02fffc0000000100 ffffea0007558e48 ffffea00071d0508 ffff8801da800940 raw: 0000000000000000 ffff8801d4974080 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801d4973f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8801d4974000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8801d4974080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801d4974100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801d4974180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ==================================================================