================================================================== BUG: KASAN: use-after-free in drm_gem_object_release_handle+0xa1/0xb0 drivers/gpu/drm/drm_gem.c:238 Read of size 8 at addr ffff8880744409e8 by task syz-executor314/3614 CPU: 1 PID: 3614 Comm: syz-executor314 Not tainted 6.0.0-rc3-syzkaller-00031-gc5e4d5e99162 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 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:238 idr_for_each+0x113/0x220 lib/idr.c:208 drm_gem_release+0x22/0x30 drivers/gpu/drm/drm_gem.c:917 drm_file_free.part.0+0x805/0xb80 drivers/gpu/drm/drm_file.c:281 drm_file_free drivers/gpu/drm/drm_file.c:248 [inline] drm_close_helper.isra.0+0x17d/0x1f0 drivers/gpu/drm/drm_file.c:308 drm_release+0x1e6/0x530 drivers/gpu/drm/drm_file.c:495 __fput+0x277/0x9d0 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+0xad5/0x29b0 kernel/exit.c:795 do_group_exit+0xd2/0x2f0 kernel/exit.c:925 __do_sys_exit_group kernel/exit.c:936 [inline] __se_sys_exit_group kernel/exit.c:934 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:934 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: 0033:0x7f54caae0349 Code: Unable to access opcode bytes at RIP 0x7f54caae031f. RSP: 002b:00007ffc991f77d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f54cab543f0 RCX: 00007f54caae0349 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 0000000100000000 R10: 0000000000000012 R11: 0000000000000246 R12: 00007f54cab543f0 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 Allocated by task 3614: 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:782 drm_ioctl+0x51e/0x9d0 drivers/gpu/drm/drm_ioctl.c:885 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 3614: 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:1754 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1780 slab_free mm/slub.c:3534 [inline] kfree+0xe2/0x580 mm/slub.c:4562 drm_gem_object_free drivers/gpu/drm/drm_gem.c:959 [inline] kref_put include/linux/kref.h:65 [inline] __drm_gem_object_put include/drm/drm_gem.h:381 [inline] drm_gem_object_put include/drm/drm_gem.h:394 [inline] drm_gem_mmap+0x4fc/0x770 drivers/gpu/drm/drm_gem.c:1119 call_mmap include/linux/fs.h:2192 [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 ffff888074440800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 488 bytes inside of 1024-byte region [ffff888074440800, ffff888074440c00) The buggy address belongs to the physical page: page:ffffea0001d11000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x74440 head:ffffea0001d11000 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 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 3608, tgid 3608 (sshd), ts 47420089282, free_ts 47415741853 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:5515 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:1824 [inline] allocate_slab+0x27e/0x3d0 mm/slub.c:1969 new_slab mm/slub.c:2029 [inline] ___slab_alloc+0x7f1/0xe10 mm/slub.c:3031 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3118 slab_alloc_node mm/slub.c:3209 [inline] __kmalloc_node_track_caller+0x2f2/0x380 mm/slub.c:4955 kmalloc_reserve net/core/skbuff.c:358 [inline] __alloc_skb+0xd9/0x2f0 net/core/skbuff.c:430 alloc_skb_fclone include/linux/skbuff.h:1307 [inline] tcp_stream_alloc_skb+0x38/0x580 net/ipv4/tcp.c:861 tcp_sendmsg_locked+0xc36/0x2f80 net/ipv4/tcp.c:1325 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1483 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:819 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:734 sock_write_iter+0x291/0x3d0 net/socket.c:1108 call_write_iter include/linux/fs.h:2187 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x9e9/0xdd0 fs/read_write.c:578 ksys_write+0x1e8/0x250 fs/read_write.c:631 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1449 [inline] free_pcp_prepare+0x5e4/0xd20 mm/page_alloc.c:1499 free_unref_page_prepare mm/page_alloc.c:3380 [inline] free_unref_page+0x19/0x4d0 mm/page_alloc.c:3476 __folio_put_large mm/swap.c:118 [inline] __folio_put+0x105/0x130 mm/swap.c:126 folio_put include/linux/mm.h:1125 [inline] put_page+0x21b/0x280 include/linux/mm.h:1177 page_to_skb+0x9e9/0xc10 drivers/net/virtio_net.c:551 receive_mergeable drivers/net/virtio_net.c:1119 [inline] receive_buf+0xe0a/0x5560 drivers/net/virtio_net.c:1258 virtnet_receive drivers/net/virtio_net.c:1553 [inline] virtnet_poll+0x708/0x1310 drivers/net/virtio_net.c:1671 __napi_poll+0xb3/0x6d0 net/core/dev.c:6511 napi_poll net/core/dev.c:6578 [inline] net_rx_action+0x9c1/0xd90 net/core/dev.c:6689 __do_softirq+0x1d3/0x9c6 kernel/softirq.c:571 Memory state around the buggy address: ffff888074440880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888074440900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888074440980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888074440a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888074440a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================