==================================================================
BUG: KASAN: slab-use-after-free in drm_atomic_helper_wait_for_vblanks.part.0+0x8c0/0x9b0 drivers/gpu/drm/drm_atomic_helper.c:1662
Read of size 1 at addr ffff888020794c09 by task kworker/u32:8/1144

CPU: 2 UID: 0 PID: 1144 Comm: kworker/u32:8 Not tainted 6.14.0-syzkaller-07422-gacb4f33713b9 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events_unbound commit_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xc3/0x670 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 drm_atomic_helper_wait_for_vblanks.part.0+0x8c0/0x9b0 drivers/gpu/drm/drm_atomic_helper.c:1662
 drm_atomic_helper_wait_for_vblanks drivers/gpu/drm/drm_atomic_helper.c:1658 [inline]
 drm_atomic_helper_commit_tail+0xcb/0xf0 drivers/gpu/drm/drm_atomic_helper.c:1758
 commit_tail+0x35b/0x400 drivers/gpu/drm/drm_atomic_helper.c:1835
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 13448:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
 kmalloc_noprof include/linux/slab.h:902 [inline]
 drm_atomic_helper_crtc_duplicate_state+0x70/0xd0 drivers/gpu/drm/drm_atomic_state_helper.c:177
 drm_atomic_get_crtc_state+0x16e/0x450 drivers/gpu/drm/drm_atomic.c:360
 drm_atomic_get_plane_state+0x436/0x590 drivers/gpu/drm/drm_atomic.c:561
 drm_atomic_set_property+0xa03/0x3360 drivers/gpu/drm/drm_atomic_uapi.c:1071
 drm_mode_atomic_ioctl+0x66f/0x25c0 drivers/gpu/drm/drm_atomic_uapi.c:1497
 drm_ioctl_kernel+0x1f1/0x3e0 drivers/gpu/drm/drm_ioctl.c:796
 drm_ioctl+0x5d6/0xc10 drivers/gpu/drm/drm_ioctl.c:893
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:906 [inline]
 __se_sys_ioctl fs/ioctl.c:892 [inline]
 __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 13446:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2376 [inline]
 slab_free mm/slub.c:4633 [inline]
 kfree+0x2b6/0x4d0 mm/slub.c:4832
 drm_atomic_state_default_clear+0x453/0xe30 drivers/gpu/drm/drm_atomic.c:224
 drm_atomic_state_clear drivers/gpu/drm/drm_atomic.c:293 [inline]
 __drm_atomic_state_free+0x185/0x2b0 drivers/gpu/drm/drm_atomic.c:310
 kref_put include/linux/kref.h:65 [inline]
 drm_atomic_state_put include/drm/drm_atomic.h:538 [inline]
 drm_client_modeset_commit_atomic+0x6b2/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1085
 drm_client_modeset_commit_locked+0x14d/0x580 drivers/gpu/drm/drm_client_modeset.c:1182
 drm_client_modeset_commit+0x4f/0x80 drivers/gpu/drm/drm_client_modeset.c:1208
 __drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:237 [inline]
 __drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:216 [inline]
 drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:264 [inline]
 drm_fb_helper_lastclose+0xc7/0x160 drivers/gpu/drm/drm_fb_helper.c:1977
 drm_fbdev_client_restore+0x2c/0x40 drivers/gpu/drm/clients/drm_fbdev_client.c:31
 drm_client_dev_restore+0x183/0x290 drivers/gpu/drm/drm_client_event.c:104
 drm_lastclose drivers/gpu/drm/drm_file.c:396 [inline]
 drm_release+0x2c2/0x360 drivers/gpu/drm/drm_file.c:429
 __fput+0x3ff/0xb70 fs/file_table.c:465
 task_work_run+0x14d/0x240 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888020794c00
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 9 bytes inside of
 freed 512-byte region [ffff888020794c00, ffff888020794e00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20794
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
ksm flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b442c80 ffffea0000a30500 dead000000000003
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b442c80 ffffea0000a30500 dead000000000003
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea000081e501 ffffffffffffffff 0000000000000000
head: 0000000000000004 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5948, tgid 5948 (syz-executor), ts 44819336340, free_ts 44698744236
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1551
 prep_new_page mm/page_alloc.c:1559 [inline]
 get_page_from_freelist+0x10c4/0x34c0 mm/page_alloc.c:3477
 __alloc_frozen_pages_noprof+0x223/0x24d0 mm/page_alloc.c:4740
 alloc_pages_mpol+0x1fb/0x540 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2446 [inline]
 allocate_slab mm/slub.c:2610 [inline]
 new_slab+0x23c/0x330 mm/slub.c:2663
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3849
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3939
 __slab_alloc_node mm/slub.c:4014 [inline]
 slab_alloc_node mm/slub.c:4175 [inline]
 __kmalloc_cache_noprof+0xfb/0x3e0 mm/slub.c:4344
 kmalloc_noprof include/linux/slab.h:902 [inline]
 kzalloc_noprof include/linux/slab.h:1036 [inline]
 rxrpc_alloc_peer+0xa7/0x400 net/rxrpc/peer_object.c:230
 rxrpc_service_prealloc_one+0xb3d/0xee0 net/rxrpc/call_accept.c:74
 rxrpc_kernel_charge_accept+0xd7/0x120 net/rxrpc/call_accept.c:475
 afs_charge_preallocation+0xce/0x330 fs/afs/rxrpc.c:739
 afs_open_socket+0x2b2/0x380 fs/afs/rxrpc.c:95
 afs_net_init+0x746/0x9f0 fs/afs/main.c:115
 ops_init+0x1df/0x5f0 net/core/net_namespace.c:138
 setup_net+0x21e/0x850 net/core/net_namespace.c:364
page last free pid 5948 tgid 5948 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_frozen_pages+0x6d8/0xf40 mm/page_alloc.c:2660
 discard_slab mm/slub.c:2707 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3176
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4138 [inline]
 slab_alloc_node mm/slub.c:4187 [inline]
 __do_kmalloc_node mm/slub.c:4317 [inline]
 __kmalloc_noprof+0x1d4/0x510 mm/slub.c:4330
 kmalloc_noprof include/linux/slab.h:906 [inline]
 do_setlink.constprop.0+0x610/0x4490 net/core/rtnetlink.c:3085
 rtnl_changelink net/core/rtnetlink.c:3766 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3925 [inline]
 rtnl_newlink+0x1446/0x2000 net/core/rtnetlink.c:4062
 rtnetlink_rcv_msg+0x95b/0xe90 net/core/rtnetlink.c:6952
 netlink_rcv_skb+0x16a/0x440 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x53a/0x7f0 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x8da/0xd70 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg net/socket.c:727 [inline]
 __sys_sendto+0x495/0x510 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2183
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888020794b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888020794b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888020794c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff888020794c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888020794d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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