================================================================== BUG: KASAN: use-after-free in drm_gem_object_release_handle+0xa1/0xb0 drivers/gpu/drm/drm_gem.c:239 Read of size 8 at addr ffff8881474549e8 by task syz-executor136/3613 CPU: 0 PID: 3613 Comm: syz-executor136 Not tainted 6.0.0-syzkaller-09589-g55be6084c8e0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold+0x2ba/0x719 mm/kasan/report.c:433 kasan_report+0xb1/0x1e0 mm/kasan/report.c:495 drm_gem_object_release_handle+0xa1/0xb0 drivers/gpu/drm/drm_gem.c:239 idr_for_each+0x113/0x220 lib/idr.c:208 drm_gem_release+0x22/0x30 drivers/gpu/drm/drm_gem.c:918 drm_file_free+0x7bb/0xb90 drivers/gpu/drm/drm_file.c:276 drm_release+0x1a6/0x4d0 drivers/gpu/drm/drm_file.c:490 __fput+0x27c/0xa90 fs/file_table.c:320 task_work_run+0xdd/0x1a0 kernel/task_work.c:177 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xb2f/0x2a20 kernel/exit.c:813 do_group_exit+0xd0/0x2a0 kernel/exit.c:943 __do_sys_exit_group kernel/exit.c:954 [inline] __se_sys_exit_group kernel/exit.c:952 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:952 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f11df434709 Code: Unable to access opcode bytes at 0x7f11df4346df. RSP: 002b:00007ffe6b342388 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f11df4a03d0 RCX: 00007f11df434709 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 0000000100000000 R10: 0000000000000012 R11: 0000000000000246 R12: 00007f11df4a03d0 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 Allocated by task 3613: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:437 [inline] ____kasan_kmalloc mm/kasan/common.c:516 [inline] ____kasan_kmalloc mm/kasan/common.c:475 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:525 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:733 [inline] vgem_gem_create_object+0x38/0xb0 drivers/gpu/drm/vgem/vgem_drv.c:98 __drm_gem_shmem_create+0x80/0x480 drivers/gpu/drm/drm_gem_shmem_helper.c:62 drm_gem_shmem_create drivers/gpu/drm/drm_gem_shmem_helper.c:127 [inline] drm_gem_shmem_create_with_handle drivers/gpu/drm/drm_gem_shmem_helper.c:424 [inline] drm_gem_shmem_dumb_create+0x13c/0x380 drivers/gpu/drm/drm_gem_shmem_helper.c:534 drm_mode_create_dumb+0x26c/0x2f0 drivers/gpu/drm/drm_dumb_buffers.c:96 drm_ioctl_kernel+0x27d/0x4e0 drivers/gpu/drm/drm_ioctl.c:788 drm_ioctl+0x3e2/0xa30 drivers/gpu/drm/drm_ioctl.c:891 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 3613: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:367 [inline] ____kasan_slab_free+0x166/0x1c0 mm/kasan/common.c:329 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1759 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1785 slab_free mm/slub.c:3539 [inline] kfree+0xe2/0x580 mm/slub.c:4567 drm_gem_object_free drivers/gpu/drm/drm_gem.c:961 [inline] kref_put include/linux/kref.h:65 [inline] __drm_gem_object_put include/drm/drm_gem.h:430 [inline] drm_gem_object_put include/drm/drm_gem.h:443 [inline] drm_gem_mmap+0x4fc/0x770 drivers/gpu/drm/drm_gem.c:1121 call_mmap include/linux/fs.h:2195 [inline] mmap_region+0xbff/0x1460 mm/mmap.c:1752 do_mmap+0x863/0xfa0 mm/mmap.c:1540 vm_mmap_pgoff+0x1ab/0x270 mm/util.c:552 ksys_mmap_pgoff+0x41b/0x5a0 mm/mmap.c:1586 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888147454800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 488 bytes inside of 1024-byte region [ffff888147454800, ffff888147454c00) The buggy address belongs to the physical page: page:ffffea00051d1400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x147450 head:ffffea00051d1400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x57ff00000010200(slab|head|node=1|zone=2|lastcpupid=0x7ff) raw: 057ff00000010200 ffffea000502cc00 dead000000000002 ffff888011841dc0 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 7647585359, free_ts 0 prep_new_page mm/page_alloc.c:2532 [inline] get_page_from_freelist+0x109b/0x2ce0 mm/page_alloc.c:4283 __alloc_pages+0x1c7/0x510 mm/page_alloc.c:5549 alloc_page_interleave+0x1e/0x200 mm/mempolicy.c:2103 alloc_pages+0x22f/0x270 mm/mempolicy.c:2265 alloc_slab_page mm/slub.c:1829 [inline] allocate_slab+0x27e/0x3d0 mm/slub.c:1974 new_slab mm/slub.c:2034 [inline] ___slab_alloc+0x84f/0xe80 mm/slub.c:3036 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3123 slab_alloc_node mm/slub.c:3214 [inline] slab_alloc mm/slub.c:3256 [inline] kmem_cache_alloc_trace+0x323/0x3e0 mm/slub.c:3287 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:733 [inline] loop_add+0x4b/0xaf0 drivers/block/loop.c:1945 loop_init+0x1f4/0x216 drivers/block/loop.c:2237 do_one_initcall+0xfe/0x650 init/main.c:1296 do_initcall_level init/main.c:1369 [inline] do_initcalls init/main.c:1385 [inline] do_basic_setup init/main.c:1404 [inline] kernel_init_freeable+0x6b1/0x73a init/main.c:1623 kernel_init+0x1a/0x1d0 init/main.c:1512 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 page_owner free stack trace missing Memory state around the buggy address: ffff888147454880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888147454900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888147454980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888147454a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888147454a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================