================================================================== BUG: KASAN: use-after-free in drm_gem_object_release_handle+0xa5/0xb0 drivers/gpu/drm/drm_gem.c:239 Read of size 8 at addr ffff888022bf31e8 by task syz-executor.2/18811 CPU: 1 PID: 18811 Comm: syz-executor.2 Not tainted 6.1.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15e/0x45d mm/kasan/report.c:395 kasan_report+0xbf/0x1f0 mm/kasan/report.c:495 drm_gem_object_release_handle+0xa5/0xb0 drivers/gpu/drm/drm_gem.c:239 idr_for_each+0x117/0x230 lib/idr.c:208 drm_gem_release+0x26/0x40 drivers/gpu/drm/drm_gem.c:918 drm_file_free.part.0+0x806/0xb50 drivers/gpu/drm/drm_file.c:276 drm_file_free drivers/gpu/drm/drm_file.c:243 [inline] drm_close_helper.isra.0+0x17d/0x1f0 drivers/gpu/drm/drm_file.c:303 drm_release+0x1e9/0x4a0 drivers/gpu/drm/drm_file.c:490 __fput+0x27c/0xa90 fs/file_table.c:320 task_work_run+0x16f/0x270 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x23c/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f9f26a3e00b Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007f9f26ccfb80 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f9f26a3e00b RDX: 00007f9f26601090 RSI: ffffffffffffffff RDI: 0000000000000003 RBP: 00007f9f26bad980 R08: 0000000000000000 R09: 00007f9f26600000 R10: 00007f9f26601098 R11: 0000000000000293 R12: 0000000000087e11 R13: 00007f9f26ccfc80 R14: 00007f9f26babf80 R15: 0000000000000032 Allocated by task 18817: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:371 [inline] ____kasan_kmalloc mm/kasan/common.c:330 [inline] __kasan_kmalloc+0xa5/0xb0 mm/kasan/common.c:380 kmalloc include/linux/slab.h:553 [inline] kzalloc include/linux/slab.h:689 [inline] vgem_gem_create_object+0x3c/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+0x140/0x380 drivers/gpu/drm/drm_gem_shmem_helper.c:534 drm_mode_create_dumb+0x270/0x300 drivers/gpu/drm/drm_dumb_buffers.c:96 drm_ioctl_kernel+0x281/0x4e0 drivers/gpu/drm/drm_ioctl.c:788 drm_ioctl+0x51a/0x980 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+0x197/0x210 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 18817: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:511 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0xaf/0x3b0 mm/slub.c:3674 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+0x4fa/0x770 drivers/gpu/drm/drm_gem.c:1121 call_mmap include/linux/fs.h:2196 [inline] mmap_region+0x6c3/0x1dd0 mm/mmap.c:2625 do_mmap+0x831/0xf60 mm/mmap.c:1412 vm_mmap_pgoff+0x1af/0x280 mm/util.c:520 ksys_mmap_pgoff+0x41f/0x5a0 mm/mmap.c:1458 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:481 kvfree_call_rcu+0x78/0x8f0 kernel/rcu/tree.c:3343 neigh_destroy+0x435/0x640 net/core/neighbour.c:912 neigh_release include/net/neighbour.h:449 [inline] neigh_cleanup_and_release+0x271/0x3d0 net/core/neighbour.c:103 neigh_periodic_work+0x616/0x9f0 net/core/neighbour.c:994 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x669/0x1090 kernel/workqueue.c:2436 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 The buggy address belongs to the object at ffff888022bf3000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 488 bytes inside of 1024-byte region [ffff888022bf3000, ffff888022bf3400) The buggy address belongs to the physical page: page:ffffea00008afc00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x22bf0 head:ffffea00008afc00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888012041dc0 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 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3627, tgid 3627 (syz-fuzzer), ts 162020548011, free_ts 162017126325 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x10b5/0x2d50 mm/page_alloc.c:4288 __alloc_pages+0x1cb/0x5b0 mm/page_alloc.c:5555 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2285 alloc_slab_page mm/slub.c:1794 [inline] allocate_slab+0x213/0x300 mm/slub.c:1939 new_slab mm/slub.c:1992 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3180 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3279 slab_alloc_node mm/slub.c:3364 [inline] __kmem_cache_alloc_node+0x199/0x3e0 mm/slub.c:3437 __do_kmalloc_node mm/slab_common.c:954 [inline] __kmalloc_node_track_caller+0x4b/0xc0 mm/slab_common.c:975 kmalloc_reserve net/core/skbuff.c:437 [inline] __alloc_skb+0xdd/0x300 net/core/skbuff.c:509 alloc_skb include/linux/skbuff.h:1267 [inline] __tcp_send_ack.part.0+0x67/0x760 net/ipv4/tcp_output.c:3960 __tcp_send_ack net/ipv4/tcp_output.c:3992 [inline] tcp_send_ack+0x81/0xa0 net/ipv4/tcp_output.c:3992 __tcp_cleanup_rbuf+0x356/0x470 net/ipv4/tcp.c:1617 tcp_recvmsg_locked+0x72c/0x22c0 net/ipv4/tcp.c:2649 tcp_recvmsg+0x117/0x620 net/ipv4/tcp.c:2679 inet_recvmsg+0x114/0x5e0 net/ipv4/af_inet.c:861 sock_recvmsg_nosec net/socket.c:995 [inline] sock_recvmsg net/socket.c:1013 [inline] sock_recvmsg net/socket.c:1009 [inline] sock_read_iter+0x348/0x480 net/socket.c:1086 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare+0x65c/0xd90 mm/page_alloc.c:1509 free_unref_page_prepare mm/page_alloc.c:3387 [inline] free_unref_page+0x1d/0x4d0 mm/page_alloc.c:3483 skb_free_frag include/linux/skbuff.h:3190 [inline] skb_free_head+0x96/0x110 net/core/skbuff.c:758 skb_release_data+0x5f1/0x870 net/core/skbuff.c:789 skb_release_all net/core/skbuff.c:854 [inline] __kfree_skb net/core/skbuff.c:868 [inline] skb_attempt_defer_free+0x304/0x3e0 net/core/skbuff.c:6640 tcp_eat_recv_skb net/ipv4/tcp.c:1638 [inline] tcp_recvmsg_locked+0x124e/0x22c0 net/ipv4/tcp.c:2633 tcp_recvmsg+0x117/0x620 net/ipv4/tcp.c:2679 inet_recvmsg+0x114/0x5e0 net/ipv4/af_inet.c:861 sock_recvmsg_nosec net/socket.c:995 [inline] sock_recvmsg net/socket.c:1013 [inline] sock_recvmsg net/socket.c:1009 [inline] sock_read_iter+0x348/0x480 net/socket.c:1086 call_read_iter include/linux/fs.h:2185 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x7fa/0x930 fs/read_write.c:470 ksys_read+0x1ec/0x250 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff888022bf3080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888022bf3100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888022bf3180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888022bf3200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888022bf3280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================