==================================================================
BUG: KASAN: use-after-free in __list_add_valid+0x81/0xa0 lib/list_debug.c:23
Read of size 8 at addr ffff88801780e2c8 by task syz-executor935/9857

CPU: 1 PID: 9857 Comm: syz-executor935 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/0x309 mm/kasan/report.c:233
 __kasan_report mm/kasan/report.c:419 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:436
 __list_add_valid+0x81/0xa0 lib/list_debug.c:23
 __list_add include/linux/list.h:67 [inline]
 list_add include/linux/list.h:86 [inline]
 fw_load_sysfs_fallback drivers/base/firmware_loader/fallback.c:516 [inline]
 fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:581 [inline]
 firmware_fallback_sysfs+0x455/0xe10 drivers/base/firmware_loader/fallback.c:657
 _request_firmware+0xa80/0xe80 drivers/base/firmware_loader/main.c:833
 request_firmware+0x32/0x50 drivers/base/firmware_loader/main.c:877
 reg_reload_regdb+0x7a/0x240 net/wireless/reg.c:1095
 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:739
 genl_family_rcv_msg net/netlink/genetlink.c:783 [inline]
 genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:800
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:811
 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
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2392
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2446
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2475
 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: 0033:0x44b3c9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 31 16 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f04399d6308 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004d72c8 RCX: 000000000044b3c9
RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000003
RBP: 00000000004d72c0 R08: 0000000000000099 R09: 0000000000000000
R10: 000000000000000c R11: 0000000000000246 R12: 00000000004d72cc
R13: 00000000004a07e0 R14: 0031313230386c6e R15: 0000000000022000

Allocated by task 9848:
 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+0x9b/0xd0 mm/kasan/common.c:522
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 __allocate_fw_priv drivers/base/firmware_loader/main.c:187 [inline]
 alloc_lookup_fw_priv drivers/base/firmware_loader/main.c:251 [inline]
 _request_firmware_prepare drivers/base/firmware_loader/main.c:746 [inline]
 _request_firmware+0x2de/0xe80 drivers/base/firmware_loader/main.c:808
 request_firmware+0x32/0x50 drivers/base/firmware_loader/main.c:877
 reg_reload_regdb+0x7a/0x240 net/wireless/reg.c:1095
 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:739
 genl_family_rcv_msg net/netlink/genetlink.c:783 [inline]
 genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:800
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:811
 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
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2392
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2446
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2475
 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 9848:
 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+0xfb/0x130 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1625 [inline]
 slab_free_freelist_hook+0xdf/0x240 mm/slub.c:1650
 slab_free mm/slub.c:3210 [inline]
 kfree+0xe4/0x530 mm/slub.c:4264
 __free_fw_priv drivers/base/firmware_loader/main.c:283 [inline]
 kref_put include/linux/kref.h:65 [inline]
 free_fw_priv+0x2b1/0x4d0 drivers/base/firmware_loader/main.c:290
 firmware_free_data drivers/base/firmware_loader/main.c:586 [inline]
 release_firmware.part.0+0xc7/0xf0 drivers/base/firmware_loader/main.c:1055
 release_firmware drivers/base/firmware_loader/main.c:842 [inline]
 _request_firmware+0x709/0xe80 drivers/base/firmware_loader/main.c:841
 request_firmware+0x32/0x50 drivers/base/firmware_loader/main.c:877
 reg_reload_regdb+0x7a/0x240 net/wireless/reg.c:1095
 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:739
 genl_family_rcv_msg net/netlink/genetlink.c:783 [inline]
 genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:800
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:811
 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
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2392
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2446
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2475
 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

The buggy address belongs to the object at ffff88801780e200
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 200 bytes inside of
 256-byte region [ffff88801780e200, ffff88801780e300)
The buggy address belongs to the page:
page:ffffea00005e0380 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1780e
head:ffffea00005e0380 order:1 compound_mapcount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888010841b40
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x52a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 9705, ts 66036064237, free_ts 65926530059
 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+0x18c/0x2a0 mm/mempolicy.c:2244
 alloc_slab_page mm/slub.c:1688 [inline]
 allocate_slab+0x32e/0x4b0 mm/slub.c:1828
 new_slab mm/slub.c:1891 [inline]
 new_slab_objects mm/slub.c:2637 [inline]
 ___slab_alloc+0x4ba/0x820 mm/slub.c:2800
 __slab_alloc.constprop.0+0xa7/0xf0 mm/slub.c:2840
 slab_alloc_node mm/slub.c:2922 [inline]
 slab_alloc mm/slub.c:2964 [inline]
 kmem_cache_alloc_trace+0x30f/0x3c0 mm/slub.c:2981
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 batadv_bla_get_backbone_gw+0xb8/0xb00 net/batman-adv/bridge_loop_avoidance.c:502
 batadv_bla_update_own_backbone_gw net/batman-adv/bridge_loop_avoidance.c:565 [inline]
 batadv_bla_tx+0x15d/0x24d0 net/batman-adv/bridge_loop_avoidance.c:2100
 batadv_interface_tx+0x45b/0x1660 net/batman-adv/soft-interface.c:238
 __netdev_start_xmit include/linux/netdevice.h:4944 [inline]
 netdev_start_xmit include/linux/netdevice.h:4958 [inline]
 xmit_one net/core/dev.c:3659 [inline]
 dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3675
 __dev_queue_xmit+0x2988/0x3620 net/core/dev.c:4285
 neigh_hh_output include/net/neighbour.h:499 [inline]
 neigh_output include/net/neighbour.h:508 [inline]
 ip6_finish_output2+0x974/0x19d0 net/ipv6/ip6_output.c:145
 __ip6_finish_output net/ipv6/ip6_output.c:210 [inline]
 __ip6_finish_output+0x4c1/0x1050 net/ipv6/ip6_output.c:189
 ip6_finish_output+0x32/0x200 net/ipv6/ip6_output.c:220
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x1e4/0x530 net/ipv6/ip6_output.c:243
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
 qlink_free mm/kasan/quarantine.c:146 [inline]
 qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272
 __kasan_slab_alloc+0x8e/0xa0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:2956 [inline]
 slab_alloc mm/slub.c:2964 [inline]
 kmem_cache_alloc_trace+0x26d/0x3c0 mm/slub.c:2981
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 nsim_fib6_rt_create drivers/net/netdevsim/fib.c:544 [inline]
 nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:749 [inline]
 nsim_fib6_event drivers/net/netdevsim/fib.c:853 [inline]
 nsim_fib_event drivers/net/netdevsim/fib.c:886 [inline]
 nsim_fib_event_work+0xe43/0x2490 drivers/net/netdevsim/fib.c:1477
 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276
 process_scheduled_works kernel/workqueue.c:2338 [inline]
 worker_thread+0x85c/0x11f0 kernel/workqueue.c:2424
 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:
 ffff88801780e180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88801780e200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88801780e280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff88801780e300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88801780e380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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