==================================================================
BUG: KASAN: use-after-free in kill_pending_fw_fallback_reqs+0x2fb/0x370 drivers/base/firmware_loader/fallback.c:116
Read of size 8 at addr ffff888039f39cc0 by task syz-executor.2/21013

CPU: 0 PID: 21013 Comm: syz-executor.2 Not tainted 5.14.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105
 print_address_description.constprop.0.cold+0x6c/0x2d6 mm/kasan/report.c:233
 __kasan_report mm/kasan/report.c:419 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:436
 kill_pending_fw_fallback_reqs+0x2fb/0x370 drivers/base/firmware_loader/fallback.c:116
 fw_pm_notify+0xa2/0x140 drivers/base/firmware_loader/main.c:1450
 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83
 notifier_call_chain_robust kernel/notifier.c:118 [inline]
 blocking_notifier_call_chain_robust kernel/notifier.c:302 [inline]
 blocking_notifier_call_chain_robust+0xc4/0x160 kernel/notifier.c:290
 pm_notifier_call_chain_robust+0x26/0x60 kernel/power/main.c:87
 snapshot_open+0x190/0x2a0 kernel/power/user.c:75
 misc_open+0x372/0x4a0 drivers/char/misc.c:141
 chrdev_open+0x266/0x770 fs/char_dev.c:414
 do_dentry_open+0x4c8/0x11d0 fs/open.c:826
 do_open fs/namei.c:3374 [inline]
 path_openat+0x1c23/0x27f0 fs/namei.c:3507
 do_filp_open+0x1aa/0x400 fs/namei.c:3534
 do_sys_openat2+0x16d/0x420 fs/open.c:1204
 do_sys_open fs/open.c:1220 [inline]
 __do_sys_openat fs/open.c:1236 [inline]
 __se_sys_openat fs/open.c:1231 [inline]
 __x64_sys_openat+0x13f/0x1f0 fs/open.c:1231
 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+0x44/0xae
RIP: 0033:0x4665e9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f1df1704188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9
RDX: 0000000000000000 RSI: 0000000020000040 RDI: ffffffffffffff9c
RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80
R13: 00007fffb803d31f R14: 00007f1df1704300 R15: 0000000000022000

Allocated by task 20770:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc mm/kasan/common.c:513 [inline]
 ____kasan_kmalloc mm/kasan/common.c:472 [inline]
 __kasan_kmalloc+0x98/0xc0 mm/kasan/common.c:522
 kasan_kmalloc include/linux/kasan.h:264 [inline]
 __do_kmalloc mm/slab.c:3702 [inline]
 __kmalloc+0x214/0x4d0 mm/slab.c:3711
 kmalloc include/linux/slab.h:596 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 lsm_superblock_alloc security/security.c:690 [inline]
 security_sb_alloc+0x101/0x240 security/security.c:893
 alloc_super+0x1e5/0xab0 fs/super.c:231
 sget_fc+0x13e/0x7c0 fs/super.c:531
 vfs_get_super fs/super.c:1135 [inline]
 get_tree_nodev+0x24/0x1d0 fs/super.c:1170
 vfs_get_tree+0x89/0x2f0 fs/super.c:1498
 do_new_mount fs/namespace.c:2905 [inline]
 path_mount+0x132a/0x1fa0 fs/namespace.c:3235
 do_mount fs/namespace.c:3248 [inline]
 __do_sys_mount fs/namespace.c:3456 [inline]
 __se_sys_mount fs/namespace.c:3433 [inline]
 __x64_sys_mount+0x27f/0x300 fs/namespace.c:3433
 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+0x44/0xae

Freed by task 8469:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:360
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free mm/kasan/common.c:328 [inline]
 __kasan_slab_free+0xcd/0x100 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:230 [inline]
 __cache_free mm/slab.c:3445 [inline]
 kfree+0x106/0x2c0 mm/slab.c:3803
 security_sb_free+0x84/0xe0 security/security.c:911
 __put_super.part.0+0x1a1/0x350 fs/super.c:295
 __put_super fs/super.c:350 [inline]
 put_super fs/super.c:313 [inline]
 deactivate_locked_super+0x13e/0x160 fs/super.c:346
 deactivate_super+0xad/0xd0 fs/super.c:366
 cleanup_mnt+0x3a2/0x540 fs/namespace.c:1136
 task_work_run+0xdd/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302
 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Last potentially related work creation:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_record_aux_stack+0xa4/0xd0 mm/kasan/generic.c:348
 kvfree_call_rcu+0x74/0x990 kernel/rcu/tree.c:3594
 drop_sysctl_table+0x3c0/0x4e0 fs/proc/proc_sysctl.c:1647
 unregister_sysctl_table fs/proc/proc_sysctl.c:1685 [inline]
 unregister_sysctl_table+0xc2/0x190 fs/proc/proc_sysctl.c:1660
 ipv6_sysctl_net_exit+0x12d/0x1f0 net/ipv6/sysctl_net_ipv6.c:302
 ops_exit_list+0xb0/0x160 net/core/net_namespace.c:175
 setup_net+0x639/0xa30 net/core/net_namespace.c:356
 copy_net_ns+0x319/0x760 net/core/net_namespace.c:474
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3002
 __do_sys_unshare kernel/fork.c:3076 [inline]
 __se_sys_unshare kernel/fork.c:3074 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3074
 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+0x44/0xae

Second to last potentially related work creation:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_record_aux_stack+0xa4/0xd0 mm/kasan/generic.c:348
 kvfree_call_rcu+0x74/0x990 kernel/rcu/tree.c:3594
 drop_sysctl_table+0x3c0/0x4e0 fs/proc/proc_sysctl.c:1647
 unregister_sysctl_table fs/proc/proc_sysctl.c:1685 [inline]
 unregister_sysctl_table+0xc2/0x190 fs/proc/proc_sysctl.c:1660
 unix_sysctl_unregister+0x58/0x80 net/unix/sysctl_net_unix.c:55
 unix_net_exit+0x11/0x50 net/unix/af_unix.c:2952
 ops_exit_list+0xb0/0x160 net/core/net_namespace.c:175
 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:595
 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff888039f39c00
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 192 bytes inside of
 256-byte region [ffff888039f39c00, ffff888039f39d00)
The buggy address belongs to the page:
page:ffffea0000e7ce40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x39f39
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffffea0000655cc8 ffffea000090f588 ffff888010840500
raw: 0000000000000000 ffff888039f39000 0000000100000008 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 8463, ts 238647613415, free_ts 238639289525
 prep_new_page mm/page_alloc.c:2436 [inline]
 get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4169
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5391
 __alloc_pages_node include/linux/gfp.h:570 [inline]
 kmem_getpages mm/slab.c:1377 [inline]
 cache_grow_begin+0x75/0x460 mm/slab.c:2593
 cache_alloc_refill+0x27f/0x380 mm/slab.c:2965
 ____cache_alloc mm/slab.c:3048 [inline]
 ____cache_alloc mm/slab.c:3031 [inline]
 __do_cache_alloc mm/slab.c:3275 [inline]
 slab_alloc mm/slab.c:3316 [inline]
 kmem_cache_alloc_trace+0x38c/0x480 mm/slab.c:3573
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 fib6_info_alloc+0xc1/0x210 net/ipv6/ip6_fib.c:155
 ip6_route_info_create+0x33e/0x1aa0 net/ipv6/route.c:3762
 ip6_route_add+0x24/0x150 net/ipv6/route.c:3856
 addrconf_prefix_route+0x30a/0x4e0 net/ipv6/addrconf.c:2415
 inet6_addr_add+0x719/0xae0 net/ipv6/addrconf.c:2948
 inet6_rtm_newaddr+0xf00/0x1970 net/ipv6/addrconf.c:4871
 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5574
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929
 sock_sendmsg_nosec net/socket.c:703 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:723
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1346 [inline]
 free_pcp_prepare+0x2c5/0x780 mm/page_alloc.c:1397
 free_unref_page_prepare mm/page_alloc.c:3332 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3411
 __vunmap+0x783/0xb70 mm/vmalloc.c:2587
 free_work+0x58/0x70 mm/vmalloc.c:82
 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
 ffff888039f39b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888039f39c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888039f39c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff888039f39d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888039f39d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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