=============================== ================================================================== BUG: KASAN: slab-use-after-free in drm_atomic_helper_wait_for_vblanks.part.0+0x7d5/0x8a0 drivers/gpu/drm/drm_atomic_helper.c:1905 Read of size 1 at addr ffff888051868009 by task kworker/u33:1/38 CPU: 3 UID: 0 PID: 38 Comm: kworker/u33:1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Workqueue: events_unbound commit_work Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x13d/0x4b0 mm/kasan/report.c:482 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 drm_atomic_helper_wait_for_vblanks.part.0+0x7d5/0x8a0 drivers/gpu/drm/drm_atomic_helper.c:1905 drm_atomic_helper_wait_for_vblanks drivers/gpu/drm/drm_atomic_helper.c:1901 [inline] drm_atomic_helper_commit_tail+0xff/0x130 drivers/gpu/drm/drm_atomic_helper.c:2003 commit_tail+0x338/0x430 drivers/gpu/drm/drm_atomic_helper.c:2080 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396 process_scheduled_works kernel/workqueue.c:3479 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560 kthread+0x373/0x450 kernel/kthread.c:436 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 6122: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x2f8/0x6d0 mm/slub.c:5563 _kmalloc_noprof include/linux/slab.h:991 [inline] drm_atomic_helper_crtc_duplicate_state+0x72/0xd0 drivers/gpu/drm/drm_atomic_state_helper.c:204 drm_atomic_get_crtc_state+0x1de/0x690 drivers/gpu/drm/drm_atomic.c:462 drm_atomic_set_property+0x165/0x3f90 drivers/gpu/drm/drm_atomic_uapi.c:1244 drm_mode_atomic_ioctl+0x6ed/0x2940 drivers/gpu/drm/drm_atomic_uapi.c:1744 drm_ioctl_kernel+0x1f3/0x3e0 drivers/gpu/drm/drm_ioctl.c:817 drm_ioctl+0x5e6/0xc60 drivers/gpu/drm/drm_ioctl.c:914 drm_compat_ioctl+0x386/0x4c0 drivers/gpu/drm/drm_ioc32.c:381 __do_compat_sys_ioctl fs/ioctl.c:695 [inline] __se_compat_sys_ioctl fs/ioctl.c:638 [inline] __ia32_compat_sys_ioctl+0x2cf/0x360 fs/ioctl.c:638 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline] __do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Freed by task 5832: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2748 [inline] slab_free mm/slub.c:6508 [inline] kfree+0x22b/0x6d0 mm/slub.c:6801 drm_atomic_commit_default_clear+0x465/0x10c0 drivers/gpu/drm/drm_atomic.c:311 drm_atomic_commit_clear drivers/gpu/drm/drm_atomic.c:394 [inline] __drm_atomic_commit_free+0x185/0x2f0 drivers/gpu/drm/drm_atomic.c:411 kref_put include/linux/kref.h:65 [inline] drm_atomic_commit_put include/drm/drm_atomic.h:713 [inline] drm_atomic_helper_dirtyfb+0x578/0x790 drivers/gpu/drm/drm_damage_helper.c:195 drm_fbdev_shmem_helper_fb_dirty+0x1cc/0x350 drivers/gpu/drm/drm_fbdev_shmem.c:117 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:339 [inline] drm_fb_helper_damage_work+0x4c8/0xab0 drivers/gpu/drm/drm_fb_helper.c:365 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396 process_scheduled_works kernel/workqueue.c:3479 [inline] worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560 kthread+0x373/0x450 kernel/kthread.c:436 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff888051868000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 9 bytes inside of freed 512-byte region [ffff888051868000, ffff888051868200) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x51868 head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000040 ffff88801c042c80 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 04fff00000000040 ffff88801c042c80 dead000000000100 dead000000000122 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 04fff00000000002 ffffffffffffff01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 503, tgid 503 (kworker/u33:7), ts 48874586911 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x110d/0x35d0 mm/page_alloc.c:3943 __alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436 alloc_slab_page mm/slub.c:3347 [inline] allocate_slab mm/slub.c:3462 [inline] new_slab+0xa9/0x6e0 mm/slub.c:3513 refill_objects+0xe3/0x410 mm/slub.c:7417 refill_sheaf mm/slub.c:2885 [inline] __pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774 alloc_from_pcs mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:4984 [inline] __do_kmalloc_node mm/slub.c:5413 [inline] __kmalloc_noprof+0x67c/0x840 mm/slub.c:5439 _kmalloc_noprof include/linux/slab.h:995 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x14c/0xad0 net/ipv6/route.c:3833 ip6_route_add+0x4b/0x1d0 net/ipv6/route.c:3962 addrconf_prefix_route+0x2fb/0x510 net/ipv6/addrconf.c:2504 addrconf_add_linklocal+0x329/0x500 net/ipv6/addrconf.c:3337 addrconf_addr_gen+0x364/0x3b0 net/ipv6/addrconf.c:3471 addrconf_dev_config net/ipv6/addrconf.c:3518 [inline] addrconf_init_auto_addrs+0x1cb/0x780 net/ipv6/addrconf.c:3596 addrconf_notify+0xa10/0x1ba0 net/ipv6/addrconf.c:3776 notifier_call_chain+0x99/0x3f0 kernel/notifier.c:85 page last free pid 5740 tgid 5740 ts 47965746620 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1418 [inline] __free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4683 [inline] slab_alloc_node mm/slub.c:4996 [inline] __kmalloc_cache_noprof+0x278/0x6d0 mm/slub.c:5559 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] ref_tracker_alloc+0x190/0x590 lib/ref_tracker.c:270 __netdev_tracker_alloc include/linux/netdevice.h:4528 [inline] netdev_hold include/linux/netdevice.h:4557 [inline] netdev_hold include/linux/netdevice.h:4552 [inline] netdev_queue_add_kobject net/core/net-sysfs.c:1973 [inline] netdev_queue_update_kobjects+0x2db/0x6f0 net/core/net-sysfs.c:2035 register_queue_kobjects net/core/net-sysfs.c:2098 [inline] netdev_register_kobject+0x2e9/0x410 net/core/net-sysfs.c:2344 register_netdevice+0x15b6/0x25a0 net/core/dev.c:11503 veth_newlink+0x316/0xce0 drivers/net/veth.c:1870 rtnl_newlink_create net/core/rtnetlink.c:3974 [inline] __rtnl_newlink net/core/rtnetlink.c:4103 [inline] rtnl_newlink+0x1697/0x2620 net/core/rtnetlink.c:4220 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:7137 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2575 netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline] netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1364 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:800 [inline] __sock_sendmsg net/socket.c:815 [inline] __sys_sendto+0x48b/0x4e0 net/socket.c:2281 Memory state around the buggy address: ffff888051867f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888051867f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888051868000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888051868080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888051868100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================